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ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following is management’s assessment of NW Holdings' and NW Natural's financial condition, including the principal factors that affect results of operations. The discussion covers the years ended December 31, 2024, 2023, and 2022 and refers to the consolidated results of NW Holdings, the substantial majority of which consist of the operating results of NW Natural. When significant activity exists at NW Holdings that does not exist at NW Natural, additional disclosure has been provided. References in this discussion to "Notes" are to the Notes to the Consolidated Financial Statements in Item 8 of this report.

NW Natural's natural gas distribution activities are reported in the natural gas distribution (NGD) segment. The NGD segment also includes NWN Gas Reserves, which is a wholly-owned subsidiary of Energy Corp, the NGD-portion of NW Natural's Mist storage facility in Oregon, and NW Natural RNG Holding Company, LLC. Other activities aggregated and reported as other at NW Natural include the non-NGD storage activity at Mist as well as asset management services and the appliance retail center operations. Other activities aggregated and reported as other at NW Holdings include NNG Financial's investment in Kelso-Beaver Pipeline (KB Pipeline); NW Natural Renewables Holdings, LLC and its non-regulated renewable natural gas activities; and NWN Water, which through itself or its subsidiaries, owns and continues to pursue investments in the water, wastewater, and water services sectors. See Note 4 for further discussion of our business segment and other, as well as our direct and indirect wholly-owned subsidiaries.

NON-GAAP FINANCIAL MEASURES. In addition to presenting the results of operations and earnings amounts in total, certain financial measures are expressed in cents per share, which are non-GAAP financial measures. All references in this section to earnings per share (EPS) are on the basis of diluted shares. We use such non-GAAP financial measures to analyze our financial performance because we believe they provide useful information to our investors, analysts, and creditors in evaluating our financial condition and results of operations. Our non-GAAP financial measures should not be considered a substitute for, or superior to, measures calculated in accordance with U.S. GAAP. Moreover, these non-GAAP financial measures have limitations in that they do not reflect all the items associated with the operations of the business as determined in accordance with GAAP. Other companies may calculate similarly titled non-GAAP financial measures differently than how such measures are calculated in this report, limiting the usefulness of those measures for comparative purposes. A reconciliation of each non-GAAP financial measure to the most directly comparable GAAP financial measure is provided below.

Diluted EPS - NW Holdings - other(2) 0.05 — 0.20

(1) Total Diluted EPS is equal to the sum of Diluted EPS - NGD segment and Diluted EPS - NW Holdings – other.

(2) Non-GAAP financial measure

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EXECUTIVE SUMMARY

NW Holdings' financial results and highlights for the year include:

•Reported net income of $78.9 million or $2.03 per share (diluted) for 2024 compared to $93.9 million or $2.59 per share (diluted) in the prior year, a decline primarily due to a regulatory disallowance and regulatory lag at NW Natural for the first 10 months of 2024 until new Oregon gas utility rates were effective on November 1, 2024;

•Added nearly 10,000 gas and water utility connections in the last twelve months for a combined growth rate of 1.1% as of December 31, 2024 mainly driven by residential customer growth across both our natural gas and water businesses;

•Invested $394.4 million in our utility systems to support greater reliability and resiliency;

•Filed an Oregon general rate case for NW Natural requesting a $59.4 million revenue requirement increase to support long-planned investments in safety and reliability;

•Closed ICH water acquisition adding wastewater and recycled water customers across Oregon, Idaho and California;

•Announced acquisition of SiEnergy, a high-growth gas utility located in Texas, in November 2024 and subsequently closed the acquisition in January 2025;

•EDL completed two unregulated RNG facilities and commenced delivery of RNG to NW Natural Renewables; and

•Increased our dividend for the 69th consecutive year to an annual indicated dividend rate of $1.96 per share.

Key financial highlights for NW Holdings include:

In millions Amount Per Share Amount Per Share Amount Per Share

Key financial highlights for NW Natural include:

In millions Amount Amount Amount

2024 COMPARED TO 2023. Consolidated net income decreased $15.7 million at NW Natural primarily due to the following factors:

•$18.2 million decrease in other income, net primarily due to higher pension costs, lower interest income from invested cash, lower regulatory interest income and a decline in the equity portion of Allowance for Funds Used During Construction (AFUDC);

•$13.7 million decrease due to the disallowance of undepreciated line extension costs as ordered in the 2024 Oregon general rate case;

•$10.1 million increase in depreciation expense from continued capital investments in our system for safety and reliability;

•$2.7 million increase in interest expense, net primarily due to higher short and long-term debt balances; and

•$2.0 million increase in general taxes primarily driven by higher regulatory commission fees; partially offset by

•$26.3 million increase in NGD segment margin driven by new rates on November 1, 2024 for Oregon, the amortization of deferred balances and customer growth; partially offset by lower usage from warmer comparative weather for customers not covered under the weather normalization mechanism;

•$3.1 million increase in gas storage revenue; and

•$1.4 million decrease in operations and maintenance expenses (excluding the regulatory disallowance) due to lower contract labor costs and lower bad debt expense, partially offset by higher amortization expense related to cloud computing arrangements.

Consolidated net income decreased $15.0 million at NW Holdings primarily due to the following factors:

•$15.7 million decrease in consolidated net income at NW Natural as discussed above; partially offset by

•$0.7 million increase in other net income primarily reflecting a $4.4 million increase in net income from water and wastewater subsidiaries, partially offset by $2.3 million of acquisition costs related to SiEnergy and higher interest expense at the holding company.

2023 COMPARED TO 2022.Consolidated net income increased $13.2 million at NW Natural primarily due to the following factors:

•$69.1 million increase in NGD segment margin driven by new rates in Oregon and Washington, actual gas prices that were lower than what was estimated in the 2022-2023 PGA, amortization of deferred balances (which is mostly offset in operations and maintenance expenses and interest expense), and customer growth; and

•$15.8 million increase in other income, net primarily due to interest income from invested cash and the equity portion of AFUDC, and lower pension costs; partially offset by

•$39.8 million increase in operations and maintenance expenses due to higher payroll costs, higher contract labor, the amortization of deferred balances (which is mostly offset in revenues), information technology costs and amortization expense related to cloud computing arrangements;

•$14.3 million increase in interest expense, net primarily due to higher long-term debt balances;

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•$6.5 million increase in depreciation expense due to additional capital investments;

•$4.8 million increase in general taxes primarily driven by higher property and payroll taxes; and

•$4.6 million increase in income tax expense due to higher pre-tax income.

Consolidated net income increased $7.6 million at NW Holdings primarily due to the following factors:

•$13.2 million increase in consolidated net income at NW Natural as discussed above; partially offset by

•$5.6 million decrease in other net income primarily reflecting higher interest expense at the holding and water companies.

CURRENT ECONOMIC AND POLITICAL CONDITIONS. We continuously review and monitor current economic conditions, which include but are not limited to: inflation and interest rates, supply chain disruptions, and other regulatory, physical or cyber related risks impacting our business. Over the prior two years, we experienced higher material and labor costs across our businesses resulting from high levels of inflation. In 2024, inflation has come down from these prior year highs and we have started to experience more traditional price impacts in 2024. Lead times on materials have returned to normal levels in 2024 for most inventory items. We continue to look for opportunities through advanced planning to ensure inventory levels are appropriately maintained. With the improved lead times we have been able to also increase inventory turnover and reduce the amounts of inventory needed on hand in 2024.

NW Holdings and NW Natural monitor interest rates and financing options for all of its businesses. While short-term rates increased considerably starting in 2022 and through 2023, the U.S. Federal Reserve started reducing short-term rates in the second half of 2024 from the highs experienced in 2023. Long-term interest rates also increased in 2022 from historically low levels, however long-term rates have since stabilized and maintained a consistent level over the past two years and are down from their highest levels in 2023. NW Natural generally recovers interest expense on its long-term debt through its authorized cost of capital. Certain working capital items, such as the cost of gas, are deferred and accrue interest in Oregon and Washington. Additionally, short-term debt is incorporated in the capital structure in Washington. NW Natural Water's regulated water and wastewater utilities generally recover interest expense from long-term debt through their respective authorized cost of capital.

We continue to monitor a wide range of new policies, executive orders, rules, initiatives and other changes to fiscal, tax, regulation, environmental, climate and other federal policies that may impact NW Natural and NW Holdings under the new U.S. Governmental Administration. Similarly, we could face significant legislative, regulatory and other policy changes at the state level or in the local jurisdictions in which we operate.

See the discussion in "Results of Operations", "Regulatory Matters" and "Financial Condition" below for additional detail regarding all significant activity that occurred during 2024.

DIVIDENDS

NW Holdings dividend highlights include:

In January 2025, the Board of Directors of NW Holdings declared a quarterly dividend on NW Holdings common stock of $0.4900 per share, payable on February 14, 2025, to shareholders of record on January 31, 2025, reflecting an indicated annual dividend rate of $1.96 per share.

See "Financial Condition - Liquidity and Capital Resources" for more information regarding the NW Holdings and NW Natural dividend policies and regulatory conditions on NW Natural dividends to its parent, NW Holdings.

RESULTS OF OPERATIONS

Regulatory Matters

Regulation and Rates

NATURAL GAS DISTRIBUTION. NW Natural's natural gas distribution business is subject to regulation by the OPUC and WUTC with respect to, among other matters, rates and terms of service, systems of accounts, and issuances of securities by NW Natural. In 2024, approximately 88% of NGD customers were located in Oregon, with the remaining 12% in Washington. Earnings and cash flows from natural gas distribution operations are largely determined by rates set in general rate cases and other proceedings in Oregon and Washington. They are also affected by weather, the local economies in Oregon and Washington, the pace of customer growth in the residential, commercial, and industrial markets, federal, state and local energy, policy, customer preferences and NW Natural's ability to remain price competitive, control expenses, and obtain reasonable and timely regulatory recovery of its natural gas distribution-related costs, including operating expenses and investment costs in plant and other regulatory assets. See "Most Recent Completed Rate Cases" below.

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MIST INTERSTATE GAS STORAGE. NW Natural's interstate storage activity at Mist is subject to regulation by the OPUC, WUTC, and the Federal Energy Regulatory Commission (FERC) with respect to, among other matters, rates and terms of service. The OPUC also regulates intrastate storage services at Mist, while FERC regulates interstate storage services at Mist. The FERC uses a maximum cost of service model which allows for gas storage prices to be set at or below the cost of service as approved by each agency in our last regulatory filing. The OPUC Schedule 80 rates are tied to the FERC rates, and are updated whenever NW Natural modifies FERC maximum rates. See "Most Recent Completed Rate Cases" below.

OTHER. The wholly-owned regulated water businesses of NWN Water, a wholly-owned subsidiary of NW Holdings, are subject to regulation by the utility commissions in the states in which they are located, which currently includes Oregon, Washington, Arizona, Idaho, and Texas. The wholly-owned regulated wastewater businesses of NWN Water are subject to regulation by the utility commissions in the states in which they are located, which currently includes Texas and Arizona.

Most Recent Completed Rate Cases

OREGON. On December 29, 2023, NW Natural filed a request for a general rate case (Rate Case) with the OPUC. On October 25, 2024, the OPUC issued an order approving two stipulations and resolving the remaining open items in the Rate Case. The final order provided for a total revenue requirement increase of $93.3 million over revenues from existing rates, which includes $9.6 million related to an updated depreciation study. The revenue requirement is based on the following assumptions:

•Capital structure of 50% common equity and 50% long-term debt;

•Return on equity of 9.4%;

•Cost of capital of 7.056%;

•Cost of long-term debt of 4.712%; and

•Average rate base of $2.09 billion or an increase of $334 million since the last rate case.

In addition to the above, the OPUC ordered the phase out of NW Natural’s line extension allowance by November 1, 2027. Additionally, the OPUC ordered a downward adjustment to rate base of $13.7 million of undepreciated line extension costs, which resulted in a non-cash, pre-tax charge of $13.7 million in the fourth quarter of 2024. In December 2024, NW Natural filed an appeal with the Oregon Court of Appeals, challenging the determination and the authority of the OPUC to take these actions.

New rates authorized by the OPUC order were effective November 1, 2024.

On October 24, 2022, the OPUC issued an order for rates effective November 1, 2022, which authorized a return on equity (ROE) of 9.4%, a cost of capital of 6.836%, and a capital structure of 50% common equity and 50% long-term debt. The OPUC further adopted an automatic adjustment clause that allows for NW Natural’s RNG project costs to be added to rates annually on November 1st.

From November 1, 2020 through October 31, 2022, the OPUC authorized rates to customers based on an ROE of 9.4% and a cost of capital of 6.965% with a capital structure of 50% common equity and 50% long-term debt. The OPUC also authorized NW Natural to recover the expense associated with the Oregon Corporate Activity Tax (CAT) as a component of base rates.

WASHINGTON.On October 21, 2021, the WUTC issued an order concluding NW Natural's general rate case filed in December 2020 (WUTC Order). The WUTC Order provides for an annual revenue requirement increase over two years, consisting of a 6.4% or $5.0 million increase in the first year beginning November 1, 2021 (Year One), and up to a 3.5% or $3.0 million increase in the second year beginning November 1, 2022 (Year Two). The increase is based on the following assumptions:

•Cost of capital of 6.814%; and

•Average rate base of $194.7 million, an increase of $20.9 million since the last rate case for capital expenditures already expended at the time of filing, with an additional expected $31.2 million increase in Year One, and an additional expected $21.4 million increase in Year Two, with the increases in Year One and Year Two relating to expected capital expenditures in those years.

The WUTC Order does not specify the underlying inputs to the cost of capital, including capital structure and return on equity. New rates authorized by the WUTC Order were effective November 1, 2021. In September 2023, NW Natural received a letter of compliance from the WUTC acknowledging that the Year Two rates are no longer subject to review and refund.

FERC.NW Natural is required under its Mist interstate storage certificate authority and rate approval orders to file every five years either a petition for rate approval or a cost and revenue study to change or justify maintaining the existing rates for its interstate storage services. NW Natural filed a rate petition with the FERC in August 2023 and the revised rates were effective beginning September 1, 2023.

NW Natural continuously evaluates the need for rate cases in its jurisdictions.

Regulatory Proceeding Updates

2025 OREGON RATE CASE.On December 30, 2024, NW Natural filed a request for a general rate increase with the OPUC. The filing includes a requested $59.4 million annual revenue requirement increase, or an approximate 5.79% increase over current customer rates. The request is based upon the following assumptions or requests:

•Capital structure of 48% long-term debt and 52% equity;

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•Return on equity of 10.4%;

•Cost of capital of 7.658%; and

•Average rate base of $2.29 billion.

The filing includes approximately $10 million related to an updated depreciation study and an increase in average rate base of $204 million compared to the last rate case for several long-planned investments by NW Natural including the following:

•Supporting reinforcement, safety and reliability of NW Natural's distribution systems and operating facilities;

•Upgrading technology to, among other things, further modernize NW Natural’s information technology infrastructure, and enhance cybersecurity protections, and

•Investing in components of NW Natural’s Mist gas storage facility, which supports service during winter heating months.

NW Natural’s filing will be reviewed by the OPUC and other stakeholders. The process is anticipated to take up to 10 months with new rates expected to take effect November 1, 2025.

Rate Mechanisms

During 2024 and 2023, NW Natural's key approved rates and recovery mechanisms for each service area included:

Oregon Washington

Authorized Rate Structure:

Return on Equity 9.4% 9.4% **

Key Regulatory Mechanisms:

Purchased Gas Adjustment (PGA) X X X

Gas Cost Incentive Sharing X X

Decoupling X X

Weather Normalization (WARM) X X

RNG Automatic Adjustment Clause X X

Environmental Cost Recovery X X X

Interstate Storage and Asset Management Sharing X X X

Annually, or more often if circumstances warrant, NW Natural reviews all regulatory assets for recoverability. If NW Natural should determine all or a portion of these regulatory assets no longer meet the criteria for continued application of regulatory accounting, then NW Natural would be required to write-off the net unrecoverable balances against earnings in the period such a determination was made.

PURCHASED GAS ADJUSTMENT. Rate changes are established for NW Natural each year under purchased gas adjustment (PGA) mechanisms in Oregon and Washington to reflect changes in the expected cost of natural gas commodity purchases. The PGA filings include costs for gas purchases, gas commodity derivative contracts, gas storage costs, gas reserves costs, pipeline demand costs, renewable natural gas and its environmental attributes, including renewable thermal certificates, and temporary rate adjustments, which amortize balances of deferred regulatory accounts.

In September 2024, NW Natural filed its annual PGAs and received OPUC and WUTC approval in October 2024. PGA rate changes were effective November 1, 2024. Rates may vary between states due to different rate structures, rate mechanisms and hedging policies.

Each year, NW Natural hedges gas prices on a portion of NW Natural's annual sales requirement based on normal weather, including both physical and financial hedges. NW Natural entered the 2024-25 gas year with total forecasted sales volume hedged at approximately 80%, including 64% in financial hedges and 16% in physical gas supplies. The total hedged was approximately 86% in Oregon and 32% in Washington.

For the subsequent two gas years, NW Natural was hedged in total between 13% and 31% for annual requirements, which consists of between 14% and 34% in Oregon and 0% and 10% in Washington. Hedge levels are subject to change based on actual load volumes, which depend to a certain extent on weather, economic conditions, and gas reserve production. Also, gas storage inventory levels may increase or decrease with storage expansion, changes in storage contracts with third parties,

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variations in the heat content of the gas, and/or storage recall by NW Natural. Gas purchases and hedges entered into for the upcoming PGA year will be included in the Company’s PGA filings in Oregon and Washington.

Under the current PGA mechanism in Oregon, there is an incentive sharing provision whereby NW Natural is required to select each year an 80% deferral or a 90% deferral of higher or lower actual gas costs compared to estimated PGA prices, such that the impact on NW Natural's current earnings from the incentive sharing is either 20% or 10% of the difference between actual and estimated gas costs, respectively. For the 2024-25 and 2023-24 gas years, NW Natural selected the 90% deferral option. Under the Washington PGA mechanism, NW Natural defers 100% of the higher or lower actual gas costs, and those gas cost differences are passed on to customers through the annual PGA rate adjustment.

As of May 1, 2024, 0.2 million therms per day of deliverability and 1.15 Bcf of associated non-utility Mist gas storage capacity was recalled to serve core customers. Customer rate increases related to this recall began on November 1, 2024.

CLIMATE COMMITMENT ACT. Washington has enacted the Climate Commitment Act (CCA), which establishes a comprehensive program that includes an overall limit for GHG emissions from major sources in the state that declines yearly. The program began January 1, 2023. In December 2024, the WUTC re-authorized a CCA cost recovery mechanism with a rate effective date of January 1, 2025. Under this mechanism, NW Natural recovers CCA costs and will defer any difference between forecasted and actual costs in the following year. Additionally, under the approved tariff, proceeds from the sale of allowances, which is required under the CCA, would be used to offset CCA compliance costs for low-income customers. Any remaining proceeds would benefit other customers through fixed bill credits or use in other carbon reduction programs.

Additionally in December 2023, the WUTC approved a request to modify NW Natural's CCA deferral to allow for the recovery of interest from customers based on the actual cash paid for purchases of allowances, less proceeds received from the sale of allowances.

EARNINGS TEST REVIEW. NW Natural is subject to an annual earnings review in Oregon to determine if the NGD business is earning above its authorized ROE threshold. If NGD business earnings exceed a specific ROE level, then 33% of the amount above that level is required to be deferred or refunded to customers. Under this provision, if NW Natural selects the 80% deferral gas cost option, then NW Natural retains all earnings up to 150 basis points above the currently authorized ROE. If NW Natural selects the 90% deferral option, then it retains all earnings up to 100 basis points above the currently authorized ROE. For the 2023-24 and 2024-25 gas years, NW Natural selected the 90% deferral option. The ROE threshold is subject to adjustment annually based on movements in long-term interest rates. For calendar years 2022, 2023, and 2024, the ROE threshold was 10.40% in all periods. There were no refunds required for 2022 and 2023. NW Natural does not expect a refund for 2024 based on results, and anticipates filing its 2024 earnings test in May 2025.

GAS RESERVES. In 2011, the OPUC approved the Encana gas reserves transaction to provide long-term gas price protection for NGD business customers and determined costs under the agreement would be recovered on an ongoing basis through the annual PGA mechanism. Gas produced from NW Natural's interests is sold at then prevailing market prices, and revenues from such sales, net of associated operating and production costs and amortization, are included in cost of gas. The cost of gas, including a carrying cost for the rate base investment made under the original agreement, is included in NW Natural's annual Oregon PGA filing, which allows NW Natural to recover these costs through customer rates. The net investment under the original agreement earns a rate of return.

In 2014, NW Natural amended the original gas reserves agreement in response to Encana's sale of its interest in the Jonah field located in Wyoming to Jonah Energy. Under the amended agreement with Jonah Energy, NW Natural has the option to invest in additional wells on a well-by-well basis with drilling costs and resulting gas volumes shared at the amended proportionate working interest for each well in which NW Natural invests. Volumes produced from the additional wells drilled after the amended agreement are included in NW Natural's Oregon PGA at a fixed rate of $0.4725 per therm. NW Natural has not participated in additional wells since 2014.

DECOUPLING. In Oregon, NW Natural has a decoupling mechanism that covers residential and some commercial sales customers. Decoupling is intended to break the link between revenue and the quantity of gas consumed by customers, removing any financial incentive to discourage customers’ efforts to conserve energy. This mechanism employs a use-per-customer decoupling calculation, which adjusts margin revenues to account for the difference between actual and expected customer volumes. The margin adjustment resulting from differences between actual and expected volumes under the decoupling component is recorded to a deferral account, which is included in the annual PGA filing. The 2024 Oregon general rate case reset the Oregon decoupling baseline usage per customer.

WARM. In Oregon, NW Natural has an approved weather normalization mechanism (WARM), which is applied to residential and small commercial customer bills. This mechanism is designed to help stabilize the collection of fixed costs by adjusting residential and small commercial customer billings based on temperature variances from average weather, with rate decreases when the weather is colder than average and rate increases when the weather is warmer than average. The mechanism is applied to bills from December through mid-May of each heating season. The mechanism adjusts the margin component of customers’ rates to reflect average weather, which uses the 25-year average temperature for each day of the billing period. Daily average temperatures and 25-year average temperatures are based on a set point temperature of 59 degrees Fahrenheit for

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residential customers and 58 degrees Fahrenheit for commercial customers. The collections of any unbilled WARM amounts due to tariff caps and floors are deferred and earn a carrying charge until collected, or returned, in the PGA the following year. Residential and small commercial customers in Oregon are allowed to opt out of the weather normalization mechanism, and as of December 31, 2024, 7% of total eligible customers had opted out. NW Natural does not have a weather normalization mechanism approved for Washington customers, which account for about 12% of total customers. See "Business Segment—Natural Gas Distribution" below.

INDUSTRIAL TARIFFS. The OPUC and WUTC have approved tariffs covering NGD service to major industrial customers, which are intended to give NW Natural certainty in the level of gas supplies needed to serve this customer group. The approved terms include, among other things, an annual election period, special pricing provisions for out-of-cycle changes, and a requirement that industrial customers complete the term of their service election under NW Natural's annual PGA tariff.

ENVIRONMENTAL COST DEFERRAL AND RECOVERY. NW Natural has authorizations in Oregon and Washington to defer costs related to remediation of properties that are owned or were previously owned by NW Natural. In Oregon, a Site Remediation and Recovery Mechanism (SRRM) is currently in place to recover prudently incurred costs allocable to Oregon customers, subject to an earnings test. Effective beginning November 1, 2019, the WUTC authorized an Environmental Cost Recovery Mechanism (ECRM) for recovery of prudently incurred costs allocable to Washington customers.

Oregon SRRM

Under the Oregon SRRM collection process, there are three types of deferred environmental remediation expense:

•Pre-review - This class of costs represents remediation spend that has not yet been deemed prudent by the OPUC. Carrying costs on these remediation expenses are recorded at NW Natural's authorized cost of capital. NW Natural anticipates the prudence review for annual costs and approval of the earnings test prescribed by the OPUC to occur by the third quarter of the following year.

•Post-review - This class of costs represents remediation spend that has been deemed prudent and allowed after applying the earnings test, but is not yet included in amortization. NW Natural earns a carrying cost on these amounts at a rate equal to the five-year treasury rate plus 100 basis points.

•Amortization - This class of costs represents amounts included in current customer rates for collection and is calculated as one-fifth of the post-review deferred balance. NW Natural earns a carrying cost equal to the amortization rate determined annually by the OPUC, which approximates a short-term borrowing rate. NW Natural included $8.8 million and $9.6 million of deferred remediation expense approved by the OPUC for collection during the 2024-25 and 2023-24 PGA years, respectively.

In addition, the SRRM also provides for the annual collection of $5.0 million from Oregon customers through a tariff rider. As it collects amounts from customers, NW Natural recognizes these collections as revenue net of any earnings test adjustments and separately amortizes an equal and offsetting amount of the deferred regulatory asset balance through the environmental remediation operating expense line shown separately in the operating expenses section of the Consolidated Statements of Comprehensive Income (Loss). See Note 17 for more information on our environmental matters.

The SRRM earnings test is an annual review of adjusted NGD ROE compared to authorized NGD ROE. To apply the earnings test NW Natural must first determine what if any costs are subject to the test through the following calculation:

Annual spend

Less: $5.0 million base rate rider

Prior year carry-over(1)

$5.0 million insurance + interest on insurance

Total deferred annual spend subject to earnings test

Less: over-earnings adjustment, if any

Add: deferred interest on annual spend(2)

Total amount transferred to post-review

(1) Prior year carry-over results when the prior year amount transferred to post-review is negative. The negative amount is carried over to offset annual spend in the following year.

(2) Deferred interest is added to annual spend to the extent the spend is recoverable.

To the extent the NGD business earns at or below its authorized ROE as defined in the SRRM, the total amount transferred to post-review is recoverable through the SRRM. To the extent more than authorized ROE is earned in a year, the amount transferred to post-review would be reduced by those earnings that exceed its authorized ROE. For 2024, NW Natural has performed this test, which is anticipated to be submitted to the OPUC in May 2025. No earnings test adjustment is expected for 2024.

Washington ECRM

The ECRM established by the WUTC order effective November 1, 2019 permits NW Natural’s recovery of environmental remediation expenses allocable to Washington customers. These expenses represent 3.32% of costs associated with

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remediation of sites that historically served both Oregon and Washington customers. The order allows for recovery of past deferred and future prudently incurred remediation costs allocable to Washington through application of insurance proceeds and collections from customers. Prudently incurred costs that were deferred from the initial deferral authorization in February 2011 through June 2019 were fully offset with insurance proceeds, with any remaining insurance proceeds to be amortized over a 10.5 year period. On an annual basis, NW Natural will file for a prudence determination and a request to recover remediation expenditures in excess of insurance amortizations in the following year's customer rates. After insurance proceeds are fully amortized, if in a particular year the request to collect deferred amounts exceeds one percent of Washington normalized revenues, then the excess will be collected over three years with interest.

INTERSTATE STORAGE AND ASSET MANAGEMENT SHARING. On an annual basis, NW Natural credits amounts to Oregon and Washington customers as part of a regulatory incentive sharing mechanism related to net revenues earned from Mist gas storage for assets developed in advance of utility customer needs, and asset management revenues. In January 2025, the OPUC approved the annual 2025 bill credit for Oregon customers' share of interstate storage and asset management activities totaling approximately $15.5 million, which was credited to customers' bills in February 2025. This includes revenue generated for the November 2023 through October 2024 PGA year. Credits are given to customers in Washington as reductions in rates through the annual PGA filing in November.

The following table presents the credits to NGD customers:

LOW INCOME DISCOUNT TARIFFS.

Oregon

In July 2022, NW Natural received approval from the OPUC for an income-qualifying residential bill discount program. The income threshold for program participation is at or below 60 percent of Oregon state median income (SMI). The program provides a bill discount for income-qualifying residential customers at four discount tier levels based on household income compared to SMI, with higher discounts given for lower income levels. The bill discount percentages were modified effective November 1, 2024 and they are presented in the table below. Participating customers can self-certify their income and household size to qualify for the program directly with NW Natural or their local Community Action Agency. The program was available for qualifying customers starting November 1, 2022. Costs for the bill discount program include simultaneous recovery from all customers. Costs for the bill discount program, inclusive of start-up and administrative costs of the program, are recoverable in rates. The amount deferred to a regulatory asset as of December 31, 2024 was $2.8 million.

Total Household Income Bill Discount Percentage

Tier 0 At or below 15% SMI 85%

Washington

In December 2023, NW Natural received approval from the WUTC for an income-qualifying residential bill discount program. The program was available for qualifying customers starting January 1, 2024. The Washington program is similar to the Oregon program, with the exception of the discount tier levels shown below. The income threshold for the Washington program participation is based on the greater of area median income (AMI) or federal poverty level (FPL). The amount deferred to a regulatory asset as of December 31, 2024 was $0.3 million.

Total Household Income Bill Discount Percentage

Tier 0 At or below 60% FPL 80%

RENEWABLE NATURAL GAS AND AUTOMATIC ADJUSTMENT CLAUSE. Oregon Senate Bill 98 (SB 98) enables natural gas utilities to procure or develop RNG on behalf of their Oregon customers. SB 98 and the rules outline the following parameters for the RNG program including: setting voluntary goals for adding as much as 30% renewable natural gas into the state’s pipeline system by 2050; enabling gas utilities to invest in and own the cleaning and conditioning equipment required to bring raw biogas and landfill gas up to pipeline quality, as well as the facilities to connect to the local gas distribution system; and allowing up to 5% of a utility’s revenue requirement to be used to cover the incremental cost or investment in renewable natural gas infrastructure.

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Further, the law supports all forms of renewable natural gas including renewable hydrogen, which is made from excess wind, solar and hydro power. Renewable hydrogen can be used for the transportation system, industrial use, or blended into the natural gas pipeline system.

NW Natural has two investments in RNG facilities the OPUC has approved for recovery in rates. The first investment is in Lexington Renewables Energy, LLC where the OPUC approved recovery through an automatic adjustment clause that allows for NW Natural's investments in RNG projects, including operating costs, to be added to rates annually on November 1st, following a prudence review. The RNG recovery mechanism allows NW Natural to defer for recovery or credit the differences between the forecasted and actual costs of the RNG projects, subject to an earnings test that includes deadbands at 50 basis points below and above NW Natural's authorized ROE. For 2024, NW Natural has performed this test, which is anticipated to be submitted to the OPUC in May 2025. No earnings test adjustment is expected for 2024.

The second investment is in Dakota City Renewable Energy LLC where the OPUC also approved the investment through an automatic adjustment clause that allows NW Natural to begin recovering the investment costs and expenses of the facility. The Dakota City investment is subject to the earnings test requirements under the RNG recovery mechanism discussed above and is subject to a production risk-sharing mechanism based on the expected per unit of production. NW Natural is required to share 25% of the costs above this threshold.

For RNG procurement contracts, NW Natural seeks recovery of the costs in the PGA and other filings, subject to a prudence review.

METER MODERNIZATION PROGRAM. In January 2024, NW Natural filed a request with the OPUC and WUTC to defer the incremental costs to replace approximately 600,000 meters over four years. The deferral was granted by the WUTC in the first quarter of 2024. The filing is pending with the OPUC. The amount deferred to a regulatory asset as of December 31, 2024 was approximately $1.4 million.

INTEGRATED RESOURCE PLAN (IRP). NW Natural generally files a full IRP biennially for Oregon and Washington with the OPUC and WUTC, respectively. NW Natural jointly filed its 2022 IRP for both Oregon and Washington on September 23, 2022. The 2022 IRP evaluates several varying scenarios based on a range of inputs and outlines the least-cost resources required to meet future demand and environmental compliance obligations. With respect to IRPs generally, the WUTC issues letters of compliance and Oregon acknowledges the IRP Action Plan. In August 2023, NW Natural received a letter of compliance from the WUTC acknowledging compliance of the 2022 IRP. The OPUC issued their order on NW Natural's 2022 IRP in August 2023.

The development of an IRP filing is an extensive and complex process that engages multiple stakeholders in an effort to build a robust and commonly understood analysis. The final product is intended to provide a long-term outlook of the supply-side and demand-side resource requirements for reliable and low-cost natural gas service while also meeting NW Natural's environmental compliance requirements. The IRP examines and analyzes uncertainties in the planning process to evaluate risk, including potential changes in governmental and regulatory policies. The CCA that was passed in Washington is an example of a new policy that resulted in compliance requirements that need to be included in the planning process. We currently expect to file our next full IRP with Oregon and Washington in 2025.

PIPELINE SECURITY.In May and July 2021, the Department of Homeland Security’s (DHS) Transportation Security Administration (TSA) released two security directives applicable to certain owners and operators of natural gas pipeline facilities (including local distribution companies). The first directive require owners and operators to implement cybersecurity incident reporting to the DHS, designate a cybersecurity coordinator, and perform a gap assessment of current entity cybersecurity practices against certain voluntary TSA security guidelines and report relevant results and proposed mitigation to applicable DHS agencies. The second directive requires entities to implement a significant number of specified cybersecurity controls and processes. The TSA updated the second directive as well as clarifying Operational Technology (OT) scope and providing a risk- and outcome-based framework. The TSA continues to renew both directives and is in the process of formulating regulations with the aim of rendering the security directives permanent. NW Natural is currently evaluating and implementing the security directives and related deliverables. NW Natural frequently updates the TSA on its progress on achieving the security directives.

NW Natural received approval from the OPUC and WUTC to defer the costs associated with complying with the TSA's security directives. As of December 31, 2024, NW Natural has invested approximately $46.9 million in information and operational technology. A majority of the capital investment was included in rate base starting November 1, 2022 in Oregon.

NW Natural continues to evaluate the potential effect of these directives on our operations and facilities and will continue to monitor for any clarifications or amendments to these directives. We may seek to request recovery from customers of any additional costs incurred to the extent that incremental expenses and capital expenditures are incurred in the future.

WATER AND WASTEWATER UTILITIES. NWN Water currently serves an estimated 190,000 people through approximately 76,000 connections across six states. NWN Water continues to pursue acquisitions of regulated water and wastewater utilities:

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•In the first quarter of 2023, NWN Water signed a purchase agreement for a water utility with approximately 700 connections in Texas. After completing a fair market valuation process through the Public Utility Commission of Texas (PUCT), NWN Water filed the application with the PUCT in the first quarter of 2024. The acquisition is expected to close in the first quarter of 2025.

•In the second quarter of 2024, NWN Water signed a purchase agreement for three water utilities with approximately 200 connections in Oregon. The OPUC approved the application in August 2024 and the acquisition closed in November 2024.

•In the fourth quarter of 2024, NWN Water signed a purchase agreement for a water utility with approximately 1,500 connections in Texas. NWN Water filed its notice of intent to seek fair market valuation with the PUCT in October 2024.

For our regulated water and wastewater utilities, we have been executing general rate cases.

•In October 2023, Foothills water and sewer utilities filed general rate cases with the ACC. The parties filed a settlement agreement in July 2024 and amended agreement in September 2024, which were approved by the ACC in October 2024. Rates were effective on November 1, 2024.

•In February 2024, Cascadia Water filed a general rate case with the WUTC. Cascadia Water and the WUTC filed a settlement agreement in January 2025 and rates are expected to be effective by May 1, 2025.

•In March 2024, Sunriver Water filed a general rate case with the OPUC and rates were effective on November 1, 2024.

•In June 2024, Avion Water filed a general rate case with the OPUC and rates were effective on February 1, 2025.

•In December 2024, Gem State Water filed a general rate case with the IPUC. The IPUC suspended the effective date of rates pending further review.

•In January 2025, Falls Water filed a general rate case with the IPUC.

Environmental Regulation and Legislation Matters

In recent years, there has been an international and domestic focus on climate change and the contribution of GHG emissions, most notably methane and carbon dioxide, to climate change. In response, there have been increasing efforts at the international, federal, state, and local level to regulate GHG emissions. Legislation or other forms of regulation have taken, and could continue to take, a variety of forms including, but not limited to, GHG emissions limits, reporting requirements, carbon taxes, requirements to purchase carbon credits, building codes, increased efficiency standards, additional charges to fund energy efficiency activities or other regulatory actions, incentives or mandates to conserve energy or use renewable energy sources, tax advantages and other subsidies to support alternative energy sources, a reduction in rate recovery for construction costs related to the installation of new customer services or other new infrastructure investments, mandates for the use of specific fuels or technologies, bans on specific fuels or technologies, or promotion of research into new technologies to reduce the cost and increase the scalability of alternative energy sources. These efforts have included, and could continue to include, legislation, legislative proposals, directed government funding, new regulations at the federal, state, and local level, and penalties for noncompliance, as well as private and other third-party litigation related to GHG emissions or regulation thereof. We recognize certain of our businesses, including our natural gas business, are likely to be affected by current or future regulation seeking to regulate GHG emissions.

Federal

A number of federal agencies currently regulate GHG emissions. For example, the EPA regulates GHG emissions pursuant to the Clean Air Act and requires the annual reporting of GHG emissions from certain industries, specified emission sources, and facilities. Under this reporting rule, local natural gas distribution companies like NW Natural are required to report system throughput to the EPA on an annual basis. The EPA also has required additional GHG reporting regulations to which NW Natural is subject, requiring the annual reporting of fugitive emissions from operations.

During his administration, former President Biden issued a number of executive orders directing agencies to conduct a general review of regulations and executive actions related to the environment and reestablished a framework for considering the social cost of carbon as part of certain agency cost-benefit analyses for new regulations. Federal legislation passed under the Biden administration, such as the Inflation Reduction Act of 2022 (IRA), included several climate and energy provisions. In addition, under the Biden administration, a number of federal agencies including the Securities and Exchange Commission (SEC), the Federal Trade Commission, the Federal Energy and Regulatory Commission, PHMSA, and the Commodities Futures Trading Commission (CFTC), had taken or were expected to take, actions related to climate change. Other federal regulatory agencies, including the U.S. Department of Energy, were additionally beginning to address matters related to GHG emissions that may include changes in their regulatory oversight approach, policies and rules.

Upon taking office in January 2025, President Trump issued executive orders directing the U.S. Ambassador to the United Nations to withdraw from the Paris Agreement on Climate and declaring a “national energy emergency” in the United States.

He issued other executive orders described as seeking to promote energy exploration and production in the United States, reducing permitting and other regulatory requirements related to energy exploration and production, freezing certain funding and regulatory rulemaking related to climate-related regulation, and revoking Biden administration executive orders that are related to climate policy. We expect there to be a number of additional changes related to climate policy under the Trump Administration, including additional executive orders, federal regulations, programs and other federal actions. We are currently evaluating the effect of various changes in federal climate policy, regulation and law, and cannot currently predict when or if the Trump Administration or Congress will act, the form of the action, or the impact of those actions on our business.

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Washington State

In 2024, Washington comprised approximately 10% of NW Natural’s revenues, as well as 2% and 13% of new meters from commercial and residential customers, respectively. Effective February, 2021, building codes in Washington state require new residential homes to achieve higher levels of energy efficiency based on specified carbon emissions assumptions, which calculate electric appliances to have lower on-site GHG emissions than comparable gas appliances. This increases the cost of new home construction incorporating natural gas depending on a number of factors including home size, equipment configurations, and building envelope measures. Additionally, in March, 2024, the Washington State Building Code Council (SBCC) implemented rules that would have the effect of restricting or eliminating the use of gas space and water heating in new commercial and residential construction, with certain exceptions in residential construction for natural gas-fired heat pumps and hybrid fuel systems.

Subsequently, Washington Ballot initiative I-2066 passed in November 2024. I-2066 was described on the ballot as prohibiting state and local governments from restricting access to natural gas, prohibiting the SBCC from discouraging or penalizing the use of natural gas in any building, requiring providers of natural gas to provide energy services regardless of the other energy sources available, and prohibiting the WUTC from approving any multiyear rate plan requiring or incentivizing a natural gas company to terminate natural gas service or make such natural gas service cost-prohibitive. The SBCC rules, as well as the effect of I-2066 on the validity of the March 2024 SBBC’s rules and the February 2021 Washington buildings codes, are currently subject to legal challenge by a number of companies, organizations and utilities, including NW Natural.

In 2022, the state of Washington enacted the Climate Commitment Act (CCA), which establishes a comprehensive program that includes an overall limit for GHG emissions from major sources in the state that declines yearly beginning January 1, 2023, resulting in an overall reduction of GHG emissions to 95% below 1990 levels by 2050. The Washington Department of Ecology has adopted rules to create a cap-and-invest program, under which entities, including natural gas and electric utilities, large manufacturing facilities, and transportation and other fuel providers, which are subject to the CCA must either reduce their emissions, purchase qualifying offsets (including RNG) or obtain allowances to cover any remaining emissions. NW Natural is subject to the CCA, has received an order authorizing deferral of CCA costs from the WUTC, and is currently recovering CCA compliance costs in rates.

Oregon

In November 2024, the ODEQ issued final cap and reduce rules for its Climate Protection Program (CPP), which became effective in January 1, 2025. The CPP establishes a program to limit GHG emissions from covered entities, including natural gas utilities, by 50% by 2035 and 90% by 2050 from a 2017-2019 baseline. The first compliance period for the CPP concludes December 31. 2027. ODEQ previously promulgated CPP rules in December 2021 (former CPP rules invalidated by the Court of Appeals in December 2023 (Prior CPP)). NW Natural received an order from the OPUC authorizing deferral of Prior CPP compliance costs, and we also expect to pursue inclusion in rates of current CPP compliance costs. The CPP rules are subject to legal challenge.

Local Jurisdictions and Other Advocacy

In addition to legislative activities at the state level, advocacy groups have indicated a willingness to pursue municipal ordinances and ballot measures or other local activities. A number of cities across the country, and several in our service territory are taking action or currently considering actions such as limitations or bans on the use of natural gas in new construction or otherwise. For example, the Eugene City Council directed its City Manager to develop a plan to address GHG emissions and align incentives around GHG emissions and to engage in a number of actions, including identifying potential revenue sources as well as potential consequences of implementing the prior directive. Similarly, some jurisdictions and advocates are seeking to ban the use of natural gas and certain natural gas appliances inside homes contending that there are detrimental indoor health effects associated with the use of natural gas.

NW Natural is actively engaged with federal, state and local policymakers, consumers, customers, small businesses and other business coalitions, economic development practitioners, and other advocates in our service territory and is working with these communities to communicate the role that direct use natural gas, and in the coming years, RNG and hydrogen, can play in pursuing more effective policies to reduce GHGs while supporting reliability, resiliency, energy choice, equity, and energy affordability.

NW Natural Decarbonization Initiatives and Compliance Actions

Our residential customers are currently paying less for their natural gas today than they did 20 years ago. We expect that compliance with any form of regulation of GHG emissions will require additional resources and legislative or regulatory tools, and will increase costs. The developing and changing guidance to implement the CCA and CPP, evolving carbon credit markets and other regulatory tool options, decades-long timeframes for compliance, likely changing and evolving laws and energy policy, and evolving technological advancements, all make it difficult to accurately predict long-term tools for and costs of compliance. We are currently including costs of compliance with the CCA in rates. Compliance costs represent a 4.6% increase on a residential bill, which represents a 7.5% decrease from the prior year. Low income customers do not participate in these compliance costs and are not impacted.

We are not currently able to quantify the extent to which limitations on natural gas use, or declining line extension allowances provided in rates to cover construction costs for new services, will affect new meter additions, or to what extent carbon

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compliance costs included in rates will affect the competitiveness of our business and the demand for natural gas service. All of these developments could negatively affect our gas utility customer growth. However, at the same time natural gas utilities will be subject to GHG emissions regulation, we expect that other energy source providers will be subject to similar, or in some cases stricter or more rapid, compliance requirements that are likely to affect their cost and competitiveness relative to natural gas as well. For example, in June 2021, the State of Oregon enacted HB 2021, a clean electricity bill that requires the state’s two largest investor-owned electric utilities and retail electricity service suppliers to reduce GHG emissions associated with electricity sold to Oregon customers to 100 percent below baseline levels by 2040 with interim steps, including an 80 percent reduction by 2030 and 90 percent reduction by 2035. This bill does not replace the separate renewable portfolio standards previously established in Oregon, which sets requirements for how much of the electricity used in Oregon must come from renewable resources. In Washington, SB 5116, the Clean Energy Transformation Act, requires all electric utilities in Washington to transition to carbon-neutral electricity by 2030 and to 100 percent carbon-free electricity by 2045. We expect compliance with these and other laws will increase the cost of energy for electric customers in our service territory. We are not able to determine at this time whether increased electricity costs will make natural gas use more or less competitive on a relative basis.

We expect these and other trends to drive innovation of, and demand for, technological developments and innovative new products that reduce GHG emissions. Research and development are occurring across the energy sector, including in the gas sector with work being conducted on gas heat pumps, higher efficiency water and space heating appliances including hybrid systems, carbon capture utilization and storage developments, continued development of technologies related to RNG, and various forms of hydrogen for different applications, among others.

Business Segment - Natural Gas Distribution (NGD)

NGD margin results are primarily affected by customer growth, revenues from rate-base additions, and, to a certain extent, by changes in delivered volumes due to weather and customers’ gas usage patterns. In Oregon, NW Natural has a conservation tariff (also called the decoupling mechanism), which adjusts margin up or down each month through a deferred regulatory accounting adjustment designed to offset changes resulting from increases or decreases in average use by residential and commercial customers. NW Natural also has a weather normalization tariff in Oregon, WARM, which adjusts customer bills up or down to offset changes in margin resulting from above- or below-average temperatures during the winter heating season. Residential and commercial customers in Oregon are allowed to opt out of the weather normalization mechanism, and as of December 31, 2024, approximately 7% of total eligible customers had opted out. NW Natural does not have a weather normalization mechanism approved for Washington customers, which account for about 12% of total customers. The decoupling and WARM mechanisms are designed to reduce, but not eliminate, the volatility of customer bills and natural gas distribution revenue. See "Regulatory Matters—Rate Mechanisms" above. In addition to NW Natural's local gas distribution business, the NGD segment also includes the portion of the Mist underground storage facility used to serve NGD customers, the North Mist gas storage expansion, NWN Gas Reserves, which is a wholly owned subsidiary of Energy Corp., and NW Natural RNG Holding Company, LLC.

The NGD business is primarily seasonal in nature due to higher gas usage by residential and commercial customers during the cold winter heating months. Other categories of customers experience seasonality in their usage but to a lesser extent. Seasonality affects the comparability of the results of operations of the NGD business across quarters but not across years.

NGD segment highlights include:

Dollars and therms in millions, except EPS data 2024 2023 2022

Diluted EPS - NGD segment $ 1.98 $ 2.59 $ 2.34

(1) See Natural Gas Distribution Margin Table below for additional detail.

2024 COMPARED TO 2023. NGD net income was $77.1 million in 2024 compared to $94.0 million in 2023. The primary factors contributing to the decrease in NGD net income were as follows:

•$18.2 million decrease in other income, net driven by higher pension non-service costs, lower interest income from invested cash, lower regulatory interest income and a decline in the equity portion of AFUDC;

•$13.7 million decrease due to the disallowance of undepreciated line extension costs as ordered in the 2024 Oregon general rate case;

•$10.1 million increase in depreciation expense from continued capital investments in our system for safety and reliability;

•$2.8 million increase in interest expense primarily due to higher short and long-term debt balances; and

•$2.0 million increase in general taxes primarily driven by higher regulatory commission fees; partially offset by

•$26.3 million increase in NGD margin primarily due to:

▪$25.8 million increase due to new customer rates in Oregon that went into effect November 1, 2024;

▪$3.7 million increase due to the amortization of deferred balances primarily related to COVID-19, cybersecurity, and ERP upgrades; and

▪$2.2 million increase driven by customer growth; partially offset by

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▪$4.3 million decrease due to lower usage from warmer comparative weather for customers not covered under the weather normalization mechanism; and

▪$1.8 million decline in gains on the Oregon gas cost incentive sharing mechanism due to market prices more closely approximating prices embedded in the PGA and higher than estimated gas costs during the cold weather event in January 2024; and

•$2.1 million decrease in NGD operations and maintenance expenses (excluding the regulatory disallowance) due to lower contract labor costs and lower bad debt expense, partially offset by higher amortization expense related to cloud computing arrangements.

Total natural gas sold and delivered in 2024 decreased 3% over 2023 primarily due to 17% warmer than average weather in 2024 compared to 8% warmer than average weather in 2023.

2023 COMPARED TO 2022. NGD net income was $94.0 million in 2023 compared to $79.7 million in 2022. The primary factors contributing to the increase in NGD net income were as follows:

•$69.1 million increase in NGD margin primarily due to:

▪$47.5 million increase due to new customer rates in Oregon and Washington that went into effect November 1, 2022;

▪$9.4 million increase due to actual gas prices that were lower than what was estimated in the 2022-2023 PGA;

▪$9.2 million increase due to the amortization of deferred balances primarily related to COVID-19, cybersecurity, and ERP upgrades (which is mostly offset in operations and maintenance expenses and interest expense; and

▪$4.6 million increase driven by customer growth; partially offset by

▪$2.4 million decrease due to warmer than average weather for customers not covered under the weather normalization mechanism.

•$15.8 million increase in other income, net driven by interest income from invested cash and the equity portion of AFUDC, and lower pension costs; partially offset by

•$40.0 million increase in NGD operations and maintenance expenses due to higher payroll costs, higher contract labor, the amortization of deferred balances (which is mostly offset in revenues), information technology costs and amortization expense related to cloud computing arrangements;

•$14.3 million increase in interest expense primarily due to higher long-term debt balances;

•$6.5 million increase in depreciation expense due to additional capital investments in the distribution system, including several significant information technology projects that were placed into service in September 2022; and

•$4.9 million higher income tax expense reflecting higher pre-tax income.

Total natural gas sold and delivered in 2023 increased 4% over 2022 primarily due to 8% warmer than average weather in 2023 compared to 1% colder than average weather in 2022.

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NATURAL GAS DISTRIBUTION MARGIN TABLE. The following table summarizes the composition of NGD gas volumes, revenues, and cost of sales:

Favorable (Unfavorable)

NGD volumes (therms):

Operating revenues:

NGD margin(1)

Degree days(2)

Percent (warmer) colder than average weather (17) % (8) % 1 %

NGD meters - end of period:

NGD meter growth:

Residential meters 0.9 % 0.6 %

Commercial meters 0.1 % 0.2 %

Industrial meters (1.1) % (0.8) %

Total meter growth 0.8 % 0.6 %

(1) Amounts reported as NGD margin for each category of meters are operating revenues less cost of gas, environmental remediation expense and revenue taxes.

(2) Heating degree days are units of measure reflecting temperature-sensitive consumption of natural gas, calculated by subtracting the average of a day's high and low temperatures from 59 degrees Fahrenheit.

(3) Average weather represents the 25-year average of heating degree days. Beginning November 1, 2024, average weather is calculated over the period June 1, 1998 through May 31, 2023, as determined in NW Natural's 2024 Oregon general rate case. From November 1, 2022 through October 31, 2024, average weather was calculated over the period June 1, 1996 through May 31, 2021, as determined in NW Natural's 2022 Oregon general rate case. From November 1, 2020 through October 31, 2022, average weather was calculated over the period June 1, 1994 through May 31, 2019, as determined in NW Natural’s 2020 Oregon general rate case.

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Residential and Commercial Sales

The primary factors that impact results of operations in the residential and commercial markets are customer growth, seasonal weather patterns, energy prices, competition from other energy sources, and economic conditions in our service areas. The impact of weather on margin is significantly reduced through NW Natural's weather normalization mechanism in Oregon; approximately 81% of NW Natural's total customers are covered under this mechanism. The remaining customers either opt out of the mechanism or are located in Washington, which does not have a similar mechanism in place. For more information on the weather mechanism, see "Regulatory Matters—Rate Mechanisms—WARM" above.

NGD residential and commercial sales highlights include:

Volumes (therms):

Operating revenues:

NGD Margin:

2024 COMPARED TO 2023. NGD residential and commercial operating revenue decreased $46.4 million and NGD margin increased $28.4 million compared to the prior year. The increase in NGD margin was primarily driven by new customer rates in Oregon that took effect on November 1, 2024 and 0.9% growth in residential customer meters. Sales volumes decreased 26.9 million therms, or 4%, due to lower usage driven by comparatively warmer weather.

2023 COMPARED TO 2022. NGD residential and commercial operating revenue increased $133.7 million and NGD margin increased $56.8 million compared to the prior year. The increase was primarily driven by new customer rates in Oregon and Washington that took effect on November 1, 2022 and 0.6% growth in residential customer meters. Sales volumes decreased 30.8 million therms, or 4%, due to lower usage driven by comparatively warmer weather.

Industrial Sales and Transportation

Industrial customers have the option of purchasing sales or transportation services. Under the sales service, the customer buys the gas commodity from NW Natural. Under the transportation service, the customer buys the gas commodity directly from a third-party gas marketer or supplier. The NGD gas commodity cost is primarily a pass-through cost to customers; therefore, NGD profit margins are not materially affected by an industrial customer's decision to purchase gas from third parties. Industrial and large commercial customers may also select between firm and interruptible service options, with firm services generally providing higher profit margins compared to interruptible services. To help manage gas supplies, industrial tariffs are designed to provide some certainty regarding industrial customers' volumes by requiring an annual service election which becomes effective November 1, special charges for changes between elections, and in some cases, a minimum or maximum volume requirement before changing options.

NGD industrial sales and transportation highlights include:

Volumes (therms):

NGD Margin:

Firm and interruptible sales $ 13.8 $ 14.1 $ 13.6

Firm and interruptible transportation 20.3 20.6 19.9

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2024 COMPARED TO 2023. NGD industrial sales and transportation margin decreased $0.6 million compared to the prior year primarily driven by lower sales and transportation volumes. Sales volumes decreased 8.9 million therms, or 2%, primarily due to lower usage from multiple customers, most notably in the pulp and paper, forest products, chemical manufacturing and food processing industries.

2023 COMPARED TO 2022. NGD industrial sales and transportation margin increased $1.2 million compared to the prior year primarily driven by new rates in Oregon and Washington that took effect on November 1, 2022, partially offset by lower sales volumes. Sales volumes decreased 14.8 million therms, or 3%, primarily due to lower usage from multiple customers, most notably in the primary metals, pulp and paper, glass, stone and clay, and chemical manufacturing industries.

Other Regulated Services Margin

Other Regulated Services primarily consist of lease revenues from NW Natural's North Mist storage facility as well as other lease revenues for compressed natural gas assets. See Note 7 for more information regarding North Mist expansion lease accounting.

Other regulated services margin highlights include:

North Mist storage services $ 19.2 $ 18.6 $ 19.4

Total other regulated services $ 19.5 $ 18.9 $ 19.6

2024 COMPARED TO 2023. Other regulated services margin increased $0.6 million compared to the prior year primarily due to an increase in storage service revenue from the North Mist facility. North Mist service revenue increased due to an increase in billing rates from higher operating expenses in 2024.

2023 COMPARED TO 2022. Other regulated services margin decreased $0.7 million compared to the prior year due to lower depreciation rates for the North Mist facility beginning November 1, 2022.

Cost of Gas

Cost of gas as reported by the NGD segment includes gas purchases, gas storage costs, gas commodity derivatives contracts, pipeline demand costs, seasonal demand cost balancing adjustments, renewable natural gas and its attributes, including renewable thermal certificates, regulatory gas cost deferrals, gas reserves costs, and company gas use. The OPUC and WUTC generally require natural gas commodity costs to be billed to customers at the actual cost incurred, or expected to be incurred. Customer rates are set each year so that if cost estimates were met the NGD business would not earn a profit or incur a loss on gas commodity purchases; however, in Oregon we have the incentive sharing mechanism described under "Regulatory Matters—Rate Mechanisms—Purchased Gas Adjustment"above. In addition to the PGA incentive sharing mechanism, gains and losses from hedge contracts entered into after annual PGA rates are effective for Oregon customers are also required to be shared and therefore may impact net income. Further, NW Natural also has a regulatory agreement whereby it earns a rate of return on its investment in the gas reserves acquired under the original agreement with Encana and includes gas from the amended gas reserves agreement at a fixed rate of $0.4725 per therm, which are also reflected in NGD margin.See "Application of Critical Accounting Policies and Estimates—Derivative Instruments and Hedging Activities" below.

Cost of gas highlights include:

Average cost of gas (cents per therm) $ 0.51 $ 0.60 $ 0.49

Gain (loss) from gas cost incentive sharing(2) $ 2.6 $ 4.5 $ (4.9)

(1) This calculation excludes volumes delivered to industrial transportation customers.

(2) For a discussion of the gas cost incentive sharing mechanism, see "Regulatory Matters—Rate Mechanisms—Purchased Gas Adjustment" above.

2024 COMPARED TO 2023. Cost of gas decreased $87.8 million, or 18%, primarily due to a 16% decrease in the average cost of gas and a 4% decrease in volumes sold. Volumes sold decreased 35.1 million due to lower usage from customers driven by comparatively warmer weather. The gain from the Oregon gas cost incentive sharing mechanism declined $1.9 million due to market prices more closely approximating prices embedded in the PGA and higher than estimated gas costs during the cold weather event in January 2024.

2023 COMPARED TO 2022. Cost of gas increased $70.2 million, or 16%, primarily due to a 21% increase in the average cost of gas with these higher gas costs embedded in the 2022-2023 PGA. Volumes sold decreased 32.9 million, or 4%, due to lower usage from customers driven by comparatively warmer weather.

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Other

Other activities aggregated and reported as other at NW Holdings include NNG Financial's investment in Kelso-Beaver Pipeline (KB Pipeline); NW Natural Renewables Holdings, LLC and its non-regulated renewable natural gas activities; NWN Water, which owns and continues to pursue investments in the water, wastewater and water services sectors; and NWN Water's investment in Avion Water Company, Inc. (Avion Water). Other activities aggregated and reported as other at NW Natural include the non-NGD storage activity at Mist as well as asset management services and the appliance retail center operations. See Note 4 for further discussion of our business segment and other, as well as our direct and indirect wholly-owned subsidiaries. See Note 13 for information on our Avion Water investment.

At Mist, NW Natural provides gas storage services to customers in the interstate and intrastate markets using storage capacity that has been developed in advance of NGD customers’ requirements. Pre-tax income from gas storage at Mist and asset management services is subject to revenue sharing with NGD customers. Under this regulatory incentive sharing mechanism, NW Natural retains 80% of pre-tax income from Mist gas storage services and asset management services when the underlying costs of the capacity being used are not included in NGD business rates. The remaining 20% is credited to a deferred regulatory account for credit to NGD customers. To the extent that the capacity used is included in NGD rates, NW Natural retains 10% of pre-tax income from such storage and asset management services and 90% is credited to NGD business customers.

The following table presents the results of activities aggregated and reported as other for both NW Holdings and NW Natural:

NW Holdings - other net loss (10.1) (10.9) (5.3)

NW Holdings - other net income (loss)(1) $ 1.8 $ (0.2) $ 6.6

Diluted earnings per share - NW Holdings - other $ 0.05 $ — $ 0.20

(1) NW Holdings - other net income (loss) is equal to the sum of NW Natural - other net income and NW Holdings – other net loss.

2024 COMPARED TO 2023. Other net income increased $2.0 million and $1.2 million at NW Holdings and NW Natural, respectively. The increase at NW Natural was primarily due to higher revenue from gas storage operations, partially offset by lower asset management revenue. The increase at NW Holdings was driven by a $4.4 million increase in net income from water and wastewater subsidiaries, partially offset by $2.3 million of acquisition costs related to SiEnergy and higher interest expense at the holding company.

2023 COMPARED TO 2022. Other net income decreased $6.8 million and $1.2 million at NW Holdings and NW Natural, respectively. The decrease at NW Natural was primarily due to lower sales at the appliance retail center. The decrease at NW Holdings was driven by higher interest expense at the holding and water companies, partially offset by a gain recognized from a settlement agreement.

Consolidated Operations

Operations and Maintenance

Operations and maintenance highlights include:

Other NW Holdings operations and maintenance 37.7 29.1 19.9

2024 COMPARED TO 2023. Operations and maintenance expense increased $12.3 million at NW Natural primarily due to the following:

•$13.7 million increase due to the disallowance of undepreciated line extension costs as ordered in the 2024 Oregon general rate case; and

•$1.4 million increase in amortization expense related to cloud computing arrangements; partially offset by

•$1.7 million decrease in contract labor costs; and

•$1.1 million decrease in bad debt expense.

Operations and maintenance expense increased $20.9 million at NW Holdings primarily due to the following:

•$12.3 million increase in operations and maintenance expense at NW Natural as discussed above; and

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•$8.6 million increase in other NW Holdings operations and maintenance expense primarily due to $7.2 million of higher costs associated with recently acquired water and wastewater subsidiaries and $1.5 million of higher operating expenses at the holding company, primarily related to SiEnergy acquisition costs.

2023 COMPARED TO 2022. Operations and maintenance expense increased $39.8 million at NW Natural primarily due to the following:

•$10.6 million increase related to higher payroll costs;

•$7.9 million increase in contract labor for safety and reliability and support for information technology system upgrades;

•$7.7 million increase due to the amortization of deferred balances (which is mostly offset in revenues) primarily related to COVID-19, cybersecurity and information technology system upgrades;

•$6.0 million increase in information technology licensing costs and maintenance;

•$5.4 million increase in amortization expense related to cloud computing arrangements; and

•$1.9 million increase in bad debt expense.

Operations and maintenance expense increased $49.1 million at NW Holdings primarily due to the following:

•$39.8 million increase in operations and maintenance expense at NW Natural as discussed above; and

•$9.3 million increase in other NW Holdings operations and maintenance expense primarily due to costs associated with recently acquired water and wastewater subsidiaries and business development costs at the holding company.

Depreciation

Depreciation highlights include:

Other NW Holdings depreciation 8.3 6.1 3.7

2024 COMPARED TO 2023. Depreciation expense increased $10.1 million for NW Natural, primarily due to additional capital investments in the distribution system, such as installing new mains and meters, replacing equipment, and upgrading and improving facilities. In addition, NW Natural continued to invest in information technology in 2024.

Depreciation expense increased $12.3 million for NW Holdings, primarily due to a $2.2 million increase in other NW Holdings depreciation related to water and wastewater subsidiaries and a $10.1 million increase at NW Natural as discussed above.

2023 COMPARED TO 2022. Depreciation expense increased $6.5 million for NW Natural, primarily due to additional capital investments in the distribution system, such as installing new mains and services and replacing regulating equipment, as well as upgrading and improving the transmission system for mains. In addition, NW Natural placed several significant information technology projects into service in September 2022 and continued to invest in information technology projects in 2023.

Depreciation expense increased $8.9 million for NW Holdings, primarily due to a $2.4 million increase in other NW Holdings depreciation related to water and wastewater subsidiaries and a $6.5 million increase at NW Natural as discussed above.

Other Income (Expense), Net

Other income (expense), net highlights include:

NW Natural total other income (expense), net $ (2.8) $ 15.4 $ (0.4)

Other NW Holdings activity 1.7 2.5 1.6

NW Holdings total other income (expense), net $ (1.1) $ 17.9 $ 1.2

Other income (expense), net primarily consists of regulatory interest, pension and other postretirement non-service costs, gains

from company-owned life insurance, the equity portion of AFUDC, interest income and donations.

2024 COMPARED TO 2023. Other income, net decreased $18.2 million at NW Natural primarily due to $6.6 million of higher pension non-service costs, $4.1 million of lower interest income from a lower level of invested cash, $2.6 million of lower regulatory interest income and a $2.6 million decline from the equity portion of AFUDC. Costs related to our defined benefit pension plan for 2024 increased compared to the prior year due to an increase in amortization of actuarial losses.

In addition to the $18.2 million decrease at NW Natural, NW Holdings experienced an additional $2.7 million decrease from a settlement gain recognized in 2023, which was partially offset by a decrease in the amount of contributions made by NW Holdings to fund community outreach initiatives in 2024.

2023 COMPARED TO 2022. Other income, net increased $15.8 million at NW Natural primarily due to $5.5 million of interest income from invested cash, $4.1 million from higher equity AFUDC interest income, and $5.8 million of lower pension costs.

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Costs related to our defined benefit pension plan for 2023 decreased compared to the prior year due to a decrease in amortization of actuarial losses.

Other income, net increased $16.7 million at NW Holdings driven by the increase at NW Natural discussed above and a $2.7 million gain recognized from a settlement agreement with a third party to settle outstanding receivables, partially offset by contributions to fund community outreach initiatives at NW Holdings.

Interest Expense, Net

Interest expense, net highlights include:

Other NW Holdings interest expense 16.8 16.0 6.9

2024 COMPARED TO 2023. Interest expense, net, increased $2.7 million at NW Natural primarily due to higher interest expense on a higher level of short and long-term debt, partially offset by the debt portion of AFUDC.

Interest expense, net, increased $3.5 million at NW Holdings due to the increase at NW Natural discussed above and higher interest expense on a higher level of long-term debt at NW Holdings.

2023 COMPARED TO 2022. Interest expense, net, increased $14.3 million at NW Natural primarily due to higher interest expense on a higher level of long-term debt, partially offset by a lower level of short-term debt.

Interest expense, net, increased $23.3 million at NW Holdings due to the increase at NW Natural discussed above and higher interest expense on a higher level of long-term debt at NW Holdings and NWN Water.

Income Tax Expense

NW Holdings income tax expense highlights include:

NW Natural income tax expense highlights include:

2024 COMPARED TO 2023. The effective tax rate increased 2.7% and 2.6% at NW Holdings and NW Natural, respectively. The increase in the effective tax rate is primarily related to a regulatory tax benefit that was fully amortized in customer rates in 2023. The decrease in income tax expense is primarily due to lower pre-tax income in the current period compared to the prior year.

2023 COMPARED TO 2022. The effective tax rate increased 0.4% and 0.1% at NW Holdings and NW Natural, respectively. The increase in the effective tax rate is primarily due to higher pre-tax income in the current period compared to the prior year.

FINANCIAL CONDITION

Capital Structure

NW Holdings' long-term goal is to maintain a strong and balanced consolidated capital structure. NW Natural has historically targeted a regulatory capital structure of 50% common equity and 50% long-term debt, which is consistent with approved regulatory allocations in Oregon, which has an allocation of 50% common equity and 50% long-term debt without recognition of short-term debt. NW Natural has requested a 52% common equity and 48% long-term debt in its current rate case, which has not yet been decided.

When additional capital is required, debt or equity securities are issued depending on both the target capital structure and market conditions. These sources of capital are also used to fund long-term debt retirements and short-term commercial paper maturities. See "Liquidity and Capital Resources" below and Note 9. Achieving our target capital structure and maintaining sufficient liquidity to meet operating requirements is necessary to maintain attractive credit ratings and provide access to the capital markets at reasonable costs.

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NW Holdings' consolidated capital structure, excluding short-term debt, was as follows:

December 31,

Long-term debt (including current maturities) 55.2 55.1

NW Natural's consolidated capital structure, excluding short-term debt, was as follows:

December 31,

Long-term debt (including current maturities) 50.8 52.5

As of December 31, 2024 and 2023, NW Holdings' consolidated capital structure included common equity of 42.4% and 43.5%, long-term debt of 51.4% and 48.3%, and short-term debt including current maturities of long-term debt of 6.2% and 8.2%, respectively. As of December 31, 2024 and 2023, NW Natural's consolidated capital structure included common equity of 46.9% and 47.2%, long-term debt of 47.2% and 52.2%, and short-term debt including current maturities of long-term debt of 5.9% and 0.6%, respectively.

During 2024, NW Natural's capital structure changed primarily due to the increase in short-term debt and capital contributions from NW Holdings. NW Holdings' capital structure changed primarily due to the issuance of long-term debt and common stock at NW Holdings. See further discussion below in "Cash Flows — Financing Activities".

Liquidity and Capital Resources

At December 31, 2024 and December 31, 2023, NW Holdings had approximately $38.5 million and $32.9 million, and NW Natural had approximately $20.0 million and $19.8 million, of cash and cash equivalents, respectively. In order to maintain sufficient liquidity during periods when capital markets are volatile, NW Holdings and NW Natural may elect to maintain higher cash balances and add short-term borrowing capacity. NW Holdings and NW Natural may also pre-fund their respective capital expenditures when long-term fixed rate environments are attractive. NW Holdings and NW Natural expect to have ample liquidity in the form of cash on hand and from operations and available credit capacity under credit facilities to support funding needs.

ATM Equity Program

In August 2021, NW Holdings initiated an at-the-market (ATM) equity program by entering into an equity distribution agreement under which NW Holdings may issue and sell from time to time shares of common stock, no par value, having an aggregate gross sales price of up to $200 million. In August 2024, the Finance Committee of the NW Holdings' Board of Directors authorized NW Holdings' sale of an additional $200 million in the aggregate gross sales price under the ATM equity program, with the result that a total of $400 million in the aggregate gross sales price has been authorized for issuance and sale under the ATM equity program. NW Holdings is under no obligation to offer and sell common stock under the ATM equity program, which the Finance Committee of the NW Holdings' Board of Directors has authorized through August 2027. Any shares of common stock offered under the ATM equity program are registered on NW Holdings’ universal shelf registration statement filed with the SEC, which expires in August 2027, or will be registered on a subsequent registration statement to be filed by NW Holdings.

During the year ended December 31, 2024, NW Holdings issued and sold 2,382,750 shares of common stock pursuant to the ATM equity program resulting in cash proceeds of $90.3 million, net of fees and commissions paid to agents of $1.6 million. As of December 31, 2024, NW Holdings had $151.6 million of equity available for issuance under the program.

NW Holdings

For NW Holdings, short-term liquidity is primarily provided by cash balances, dividends from its operating subsidiaries, in particular NW Natural, available cash from a multi-year credit facility, and short-term credit facilities. NW Holdings also has a universal shelf registration statement filed with the SEC for the issuance of debt and equity securities. NW Holdings long-term debt and equity issuances are primarily used to provide equity contributions to NW Holdings’ operating subsidiaries for operating and capital expenditures and other corporate purposes. NW Natural also has a universal shelf registration statement filed with the SEC for the issuance of debt securities. NW Holdings' issuance of securities is not subject to regulation by state public utility commissions, but the dividends from NW Natural to NW Holdings are subject to regulatory ring-fencing provisions. NW Holdings guarantees the debt of its wholly-owned subsidiary, NWN Water. See "Long-Term Debt" below for more information regarding NWN Water debt.

As part of the ring-fencing conditions agreed upon with the OPUC and WUTC in connection with the holding company reorganization, NW Natural may not pay dividends or make distributions to NW Holdings if NW Natural’s credit ratings and common equity ratio, defined as the ratio of equity to long-term debt, fall below specified levels. If NW Natural’s long-term

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secured credit ratings are below A- for S&P and A3 for Moody’s, dividends may be issued so long as NW Natural’s common equity ratio is 45% or more. If NW Natural’s long-term secured credit ratings are below BBB for S&P and Baa2 for Moody’s, dividends may be issued so long as NW Natural’s common equity ratio is 46% or more. Dividends may not be issued if NW Natural’s long-term secured credit ratings are BB+ or below for S&P or Ba1 or below for Moody’s, or if NW Natural’s common equity ratio is below 44%, where the ratio is measured using common equity and long-term debt excluding imputed debt or debt-like lease obligations. In each case, common equity ratios are determined based on a preceding or projected 13-month average. In addition, there are certain OPUC notice requirements for dividends in excess of 5% of NW Natural’s retained earnings.

Additionally, if NW Natural’s common equity (excluding goodwill and equity associated with non-regulated assets), on a preceding or projected 13-month average basis, is less than 46% of NW Natural’s capital structure, NW Natural is required to notify the OPUC, and if the common equity ratio falls below 44%, file a plan with the OPUC to restore its equity ratio to 44%. This condition is designed to ensure NW Natural continues to be adequately capitalized under the holding company structure. Under the WUTC order, the average common equity ratio must not exceed 56%.

At December 31, 2024 and 2023, NW Natural satisfied the ring-fencing provisions described above.

Based on several factors, including current cash reserves, committed credit facilities, its ability to receive dividends from its operating subsidiaries, in particular NW Natural, and an expected ability to issue long-term debt and equity securities in the capital markets, NW Holdings believes its liquidity is sufficient to meet anticipated near-term cash requirements, including all contractual obligations, investing, and financing activities as discussed in "Cash Flows" below.

NW HOLDINGS DIVIDENDS. Quarterly dividends have been paid on common stock each year since NW Holdings’ predecessor’s stock was first issued to the public in 1951. Annual common stock dividend payments per share, adjusted for stock splits, have increased each year since 1956. The declarations and amount of future dividends to shareholders will depend upon earnings, cash flows, financial condition, NW Natural’s ability to pay dividends to NW Holdings and other factors. The amount and timing of dividends payable on common stock is at the sole discretion of the NW Holdings Board of Directors.

NW Natural

For the NGD business segment, short-term borrowing requirements typically peak during colder winter months when the NGD business borrows money to cover the lag between natural gas purchases and bill collections from customers. Short-term liquidity for the NGD business is primarily provided by cash balances, internal cash flow from operations, proceeds from the sale of commercial paper notes, as well as available cash from multi-year credit facilities, short-term credit facilities, company-owned life insurance policies, the sale of long-term debt, and equity contributions from NW Holdings. NW Natural's long-term debt and contributions from NW Holdings are primarily used to finance NGD capital expenditures, refinance maturing debt, and provide temporary funding for other general corporate purposes of the NGD business.

Based on its current debt ratings (see "Credit Ratings" below), NW Natural has been able to issue commercial paper and long-term debt at attractive rates. In the event NW Natural is not able to issue new long-term debt due to adverse market conditions or other reasons, NW Natural expects that near-term liquidity needs can be met using internal cash flows, issuing commercial paper, receiving equity contributions from NW Holdings, or drawing upon a committed credit facility. NW Natural also has a universal shelf registration statement filed with the SEC for the issuance of secured and unsecured debt securities.

In the event senior unsecured long-term debt ratings are downgraded, or outstanding derivative positions exceed a certain credit threshold, counterparties under derivative contracts could require NW Natural to post cash, a letter of credit, or other forms of collateral, which could expose NW Natural to additional cash requirements and may trigger increases in short-term borrowings while in a net loss position. NW Natural was not required to post collateral at December 31, 2024. See Note 15 below.

Other items that may have a significant impact on NW Natural's liquidity and capital resources include NW Natural's pension contribution requirements and environmental expenditures.

PENSION CONTRIBUTIONS. NW Natural expects to make contributions to its company-sponsored defined benefit plan, which is closed to new employees, over the next several years under applicable laws and regulations. See "Application of Critical Accounting Policies—Pensions and Postretirement Benefits" below and Note 10 for more information.

ENVIRONMENTAL EXPENDITURES. NW Natural expects to continue using cash resources to fund environmental liabilities for future environmental remediation or action. NW Natural has authorizations in Oregon and Washington to defer costs related to remediation of properties that are owned or were previously owned by NW Natural. In Oregon, a Site Remediation and Recovery Mechanism (SRRM) is currently in place to recover prudently incurred costs allocable to Oregon customers, subject to an earnings test. On October 21, 2019 the WUTC authorized an Environmental Cost Recovery Mechanism (ECRM) for recovery of prudently incurred costs allocable to Washington customers beginning November 1, 2019. See Note 17 and "Results of Operations—Regulatory Matters—Environmental Cost Deferral and Recovery" above.

Based on several factors, including current credit ratings, NW Natural's commercial paper program, current cash reserves, committed credit facilities, and an expected ability to issue long-term debt and receive equity contributions from NW Holdings,

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NW Natural believes its liquidity is sufficient to meet anticipated near-term cash requirements, including all contractual obligations, and investing and financing activities as discussed in "Cash Flows" below.

NW NATURAL DIVIDENDS. The declarations and amount of future dividends to NW Holdings will depend upon earnings, cash flows, financial condition, the satisfaction of OPUC and WUTC regulatory ring-fencing restrictions, and other factors. The amount and timing of dividends payable on common stock is subject to approval of the NW Natural Board of Directors.

Gas and Pipeline Capacity Purchase Agreements

NW Natural has signed agreements providing for the reservation of firm pipeline capacity under which it is required to make monthly payments for contracted capacity. The pricing component of the monthly payment is established, subject to change, by U.S. or Canadian regulatory bodies, or is established directly with private counterparties, as applicable. In addition, NW Natural has entered into long-term agreements to release firm pipeline capacity. NW Natural also enters into short-term and long-term gas purchase agreements. Refer to Note 16 for gas and pipeline capacity purchase commitments.

NW Natural Renewables is an unregulated subsidiary of NW Natural Holdings established to pursue unregulated RNG activities. In September 2021, a subsidiary of NW Natural Renewables, Ohio Renewables, and a subsidiary of EDL, a global producer of sustainable distributed energy, executed agreements to secure RNG supply from two production facilities that are designed to convert landfill waste gases to RNG (EDL Facilities). The first facility was completed and commenced delivery of RNG to Ohio Renewables in September 2024. Upon reaching this milestone, Ohio Renewables paid $26.0 million to the EDL subsidiary. The second facility was completed and commenced delivery of RNG to Ohio Renewables in December 2024 at which point Ohio Renewables made an additional payment of $25.4 million to the EDL subsidiary.

Alongside these development agreements, Ohio Renewables and the subsidiary of EDL executed agreements for Ohio Renewables to purchase up to an annual specified amount of RNG produced by the EDL Facilities over a 20-year period at a contractually specified price. Under the amended agreements, we currently estimate the amount of RNG purchases based on prices and quantities specified in the agreements to be as follows: approximately $18.9 million in 2025, $18.9 million in 2026, $22.8 million in 2027, $22.8 million in 2028, $24.1 million in 2029 and $532.6 million thereafter.

Gas Sale Agreements

Ohio Renewables has contracted to sell RNG produced by the EDL Facilities up to certain specified volumes in each of calendar years 2024 through 2026 to an investment-grade counterparty. We currently estimate RNG volumes to be sold pursuant to this agreement to be approximately 2,430,000 MMbtu over the life of the agreement, provided that such amounts of RNG are produced by the EDL Facilities during that period.

Ohio Renewables additionally has contracted to sell a fixed-volume of RNG under a long-term agreement with an investment-grade utility beginning in 2025 and extending through 2042. Amounts to be delivered under this agreement are estimated to be 112,500 MMbtu in 2025, 375,000 MMbtu in 2026, 1,950,000 MMbtu annually in 2027 through 2034, and 2,775,000 MMbtu annually in years 2035 through 2042. Under the current contract, if less than 75% of the contracted volumes of RNG are not delivered on an annual basis, Ohio Renewables is obligated to pay the per MMbtu price for volumes between the amount delivered and 75% of the contracted volumes on an annual basis.

Other Purchase Agreements

Other purchase commitments primarily consist of remaining balances under existing purchase orders and gas storage agreements. At December 31, 2024, the amount due over the duration of the purchase agreements totaled $22.5 million. Except for these certain purchase commitments, NW Holdings and NW Natural have no material off-balance sheet financing arrangements.

Short-Term Debt

The primary source of short-term liquidity for NW Holdings is cash balances, dividends from its operating subsidiaries, in particular NW Natural, available cash from a multi-year credit facility, and short-term credit facilities it may enter into from time to time.

The primary source of short-term liquidity for NW Natural is from the sale of commercial paper, available cash from a multi-year credit facility, and short-term credit facilities it may enter into from time to time. In addition to issuing commercial paper or entering into bank loans to meet working capital requirements, including seasonal requirements to finance gas purchases and accounts receivable, short-term debt may also be used to temporarily fund capital requirements. For NW Natural, commercial paper and bank loans are periodically refinanced through the sale of long-term debt or equity contributions from NW Holdings. Commercial paper, when outstanding, is sold through two commercial banks under an issuing and paying agency agreement and is supported by one or more unsecured revolving credit facilities. See “Credit Agreements” below.

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At December 31, 2024 and 2023, NW Natural's short-term debt consisted of the following:

NW Natural:

Other (NW Holdings):

(1)Weighted average interest rate on outstanding short-term debt

Credit Agreements

NW Holdings

NW Holdings has a $200 million sustainability-linked credit agreement, with a feature that allows it to request increases in the total commitment amount, up to a maximum of $300 million. In December 2024, the maturity date of the agreement was extended to November 2, 2027, with an available extension of commitments for one additional one-year period, subject to lender approval.

All lenders under the NW Holdings credit agreement are major financial institutions with committed balances and investment grade credit ratings as of December 31, 2024 as follows:

In millions

Lender rating, by category Loan Commitment

Based on credit market conditions, it is possible one or more lending commitments could be unavailable to NW Holdings if the lender defaulted due to lack of funds or insolvency; however, NW Holdings does not believe this risk to be imminent due to the lenders' strong investment-grade credit ratings. There was $33.6 million and $73.0 million of outstanding balances under the NW Holdings agreement at December 31, 2024 and 2023, respectively.

The NW Holdings credit agreement permits the issuance of letters of credit in an aggregate amount of up to $40 million. The principal amount of borrowings under the credit agreement is due and payable on the maturity date. The credit agreement requires NW Holdings to maintain a consolidated indebtedness to total capitalization ratio of 70% or less. Failure to comply with this covenant would entitle the lenders to terminate their lending commitments and accelerate the maturity of all amounts outstanding. NW Holdings was in compliance with this covenant at December 31, 2024 and 2023, with consolidated indebtedness to total capitalization ratios of 57.6% and 56.5%, respectively.

The NW Holdings credit agreement also requires NW Holdings to maintain debt ratings (which are defined by a formula using NW Natural's credit ratings in the event NW Holdings does not have a credit rating) with Standard & Poor's (S&P) and Moody's Investors Service, Inc. (Moody’s) and notify the lenders of any change in its senior unsecured debt ratings or senior secured debt ratings, as applicable, by such rating agencies. A change in NW Holdings' debt ratings by S&P or Moody’s is not an event of default, nor is the maintenance of a specific minimum level of debt rating a condition of drawing upon the credit agreement. Rather, interest rates on any loans outstanding under the credit agreements are tied to debt ratings and therefore, a change in the debt rating would increase or decrease the cost of any loans under the credit agreements when ratings are changed. NW Holdings maintains a credit rating with S&P of A- and does not currently maintain ratings with Moody's.

NW Holdings had no letters of credit issued and outstanding at December 31, 2024 and 2023.

NW Natural

NW Natural has a sustainability-linked multi-year credit agreement for unsecured revolving loans totaling $400 million, with a feature that allows NW Natural to request increases in the total commitment amount, up to a maximum of $600 million. In December 2024, the maturity date of the agreement was extended to November 3, 2027 with an available extension of commitments for one additional one-year period, subject to lender approval.

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All lenders under the NW Natural credit agreement are major financial institutions with committed balances and investment grade credit ratings as of December 31, 2024 as follows:

In millions

Lender rating, by category Loan Commitment

Based on credit market conditions, it is possible one or more lending commitments could be unavailable to NW Natural if the lender defaulted due to lack of funds or insolvency; however, NW Natural does not believe this risk to be imminent due to the lenders' strong investment-grade credit ratings.

The NW Natural credit agreement permits the issuance of letters of credit in an aggregate amount of up to $60 million. The principal amount of borrowings under the credit agreement is due and payable on the maturity date. There were no outstanding balances under this credit agreement at December 31, 2024 or 2023. The credit agreement requires NW Natural to maintain a consolidated indebtedness to total capitalization ratio of 70% or less. Failure to comply with this covenant would entitle the lenders to terminate their lending commitments and accelerate the maturity of all amounts outstanding. NW Natural was in compliance with this covenant at December 31, 2024 and 2023, with consolidated indebtedness to total capitalization ratios of 53.1% and 52.8%, respectively.

The NW Natural credit agreement also requires NW Natural to maintain credit ratings with S&P and Moody’s and notify the lenders of any change in NW Natural's senior unsecured debt ratings or senior secured debt ratings, as applicable, by such rating agencies. A change in NW Natural's debt ratings by S&P or Moody’s is not an event of default, nor is the maintenance of a specific minimum level of debt rating a condition of drawing upon the credit agreement. Rather, interest rates on any loans outstanding under the credit agreement are tied to debt ratings and therefore, a change in the debt rating would increase or decrease the cost of any loans under the credit agreement when ratings are changed. See "Credit Ratings" below.

NW Natural had no letters of credit outstanding at December 31, 2024 and one letter of credit outstanding at December 31, 2023. In December 2023, NW Natural issued a $15 million letter of credit through its existing credit agreement, which expired January 5, 2024.

Letters of Credit Facility

In January 2024, NW Natural entered into an Uncommitted Letter of Credit and Reimbursement Agreement (LC Reimbursement Agreement), pursuant to which NW Natural agreed to reimburse each Lender acting as an issuing bank (Issuing Bank) thereunder for disbursements in respect of letters of credit (Letters of Credit) issued pursuant to the LC Reimbursement Agreement from time to time. The Company expects to use Letters of Credit issued under the facility created by the LC Reimbursement Agreement (LC Facility) primarily to support its participation in Washington Climate Commitment Act cap-and-invest program auctions.

Although there is no expressly stated maximum amount of Letters of Credit that can be issued or outstanding under the LC Facility, under current regulatory authority from the OPUC, the aggregate sum of Letters of Credit outstanding and available to be drawn under the LC Reimbursement Agreement may not exceed $100 million at any one time. The Issuing Banks have no commitment to issue Letters of Credit under the LC Facility and will have the discretion to limit and condition the terms for the issuance of Letters of Credit (including maximum face amounts) in their sole discretion.

The LC Reimbursement Agreement requires NW Natural to maintain certain ratings with S&P and Moody’s. NW Natural must also notify the Administrative Agent and Lenders of any change in the S&P or Moody’s Ratings, although any such change is not an event of default.

The LC Reimbursement Agreement prohibits NW Natural from permitting Consolidated Indebtedness to be greater than 70% of Total Capitalization, each as defined therein and calculated as of the end of each fiscal quarter of NW Natural. Failure to comply with this financial covenant would constitute an Event of Default under the LC Reimbursement Agreement. The occurrence of this or any other Event of Default would entitle the Administrative Agent to require cash collateral for the LC Exposure, as defined in the LC Reimbursement Agreement, and to exercise all other rights and remedies available to it and the Lenders under the Credit Documents, as defined in the LC Reimbursement Agreement, and under applicable law.

There were no letter of credits issued or outstanding under the LC reimbursement agreement at December 31, 2024.

Credit Ratings

NW Natural's credit ratings are a factor of liquidity, potentially affecting access to the capital markets including the commercial paper market. NW Natural's credit ratings also have an impact on the cost of funds, and may have an impact on the need to post collateral under financial derivative contracts.

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The following table summarizes NW Natural's current credit ratings:

S&P Moody's

Commercial paper (short-term debt) A-1 P-2

Senior secured (long-term debt) AA- A2

Senior unsecured (long-term debt) n/a Baa1

Issuer credit rating A+ n/a

Ratings outlook Stable Stable

In November 2024, S&P revised NW Holdings' rating from A to A- and ratings outlook from "negative" to "stable."

The above credit ratings and ratings outlook are dependent upon a number of factors, both qualitative and quantitative, and are subject to change at any time. The disclosure of or reference to these credit ratings is not a recommendation to buy, sell or hold NW Holdings or NW Natural securities. Each rating should be evaluated independently of any other rating.

As part of the ring-fencing conditions agreed upon with the OPUC and WUTC, NW Holdings and NW Natural are required to maintain separate credit ratings, long-term debt ratings, and preferred stock ratings, if any.

Long-Term Debt

Note Purchase Agreement

In December 2023, NW Holdings entered into a Note Purchase Agreement between NW Holdings and the institutional investors named as purchasers therein. The Note Purchase Agreement provides for the issuance of (i) $100.0 million aggregate principal amount of NW Holdings’ 5.78% Senior Notes, Series A, due March 7, 2028 (5.78% Notes) and (ii) $50.0 million aggregate principal amount of NW Holdings’ 5.84% Senior Notes, Series B, due March 7, 2029 (5.84% Notes) in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended. The 5.78% Notes and the 5.84% Notes were issued in March 2024, pursuant to the Note Purchase Agreement. The proceeds from the Note Purchase Agreement were used to settle an existing term loan at NW Holdings for $100.0 million and make an equity contribution to NWN Water, which was used to settle an existing term loan for $50.0 million.

Issuance of Long-Term Debt

In December 2024, NW Holdings issued and sold (i) $90.0 million in aggregate principal amount of its 5.52% Senior Notes, Series C, due December 19, 2029 (the 5.52% Notes), and (ii)$45.0 million in aggregate principal amount of its 5.86% Senior Notes, Series D, due December 19, 2034 (the 5.86% Notes, together with the 5.52% Notes, the Notes), to certain institutional investors pursuant to a Note Purchase Agreement dated December 19, 2024 (the Note Purchase Agreement), in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended.

The 5.52% Notes and the 5.86% Notes bear interest at the rate of 5.52% and 5.86%, respectively, per annum, payable semi-annually on June 19 and December 19 of each year, commencing June 19, 2025, and will mature on December 19, 2029, and December 19, 2034, respectively. The 5.52% Notes and the 5.86% Notes will be subject to prepayment at the option of NW Holdings, in whole or in part, (i) at any time at a price equal to 100% of the principal amount thereof, plus the applicable “make-whole” premium and accrued and unpaid interest thereon to the date of prepayment, and (ii) at any time on or after November 19, 2029 and September 19, 2034, respectively, at 100% of the principal amount thereof, plus accrued and unpaid interest thereon to the date of prepayment, but without the payment of a “make-whole” premium, in each case, so long as there is no Default or Event of Default under the Note Purchase Agreement.

Interest Rate Swap Agreement

In January 2023, NWN Water entered into an interest rate swap agreement with a major financial institution for $55.0 million that effectively converted variable-rate debt to a fixed rate of 3.80%. Interest payments made between the effective date and expiration date are hedged by the swap agreement. The interest rate swap agreement expires in June 2026, along with the variable-rate debt.

Retirement of Long-Term Debt

The following NW Natural debentures were retired in the periods indicated:

Year Ended December 31,

NW Natural First Mortgage Bonds:

Total $ — $ 90 $ —

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In March 2024, NW Holdings retired a $100.0 million credit agreement and NWN Water retired a $50.0 million credit agreement.

Maturities and Interest on Long-Term Debt

Maturities and payment of interest on long-term debt for each of the annual periods through December 31, 2029 and thereafter are as follows:

In millions Long-term debt maturities Interest on long-term debt

NW Natural:

Other NW Holdings:

NW Holdings:

Bankruptcy Ring-fencing Restrictions

As part of the ring-fencing conditions agreed upon with the OPUC and WUTC, NW Natural is required to have one director who is independent from NW Natural management and from NW Holdings and to issue one share of NW Natural preferred stock to an independent third party. NW Natural was in compliance with both of these ring-fencing provisions as of December 31, 2024 and 2023. NW Natural may file a voluntary petition for bankruptcy only if approved unanimously by the Board of Directors of NW Natural, including the independent director, and by the holder of the preferred share.

Cash Flows

Operating Activities

Changes in our operating cash flows are primarily affected by net income or loss, changes in working capital requirements, and other cash and non-cash adjustments to operating results.

NW Natural cash provided by operating activities $ 230.7 $ 281.9 $ 145.2

NW Holdings cash provided by operating activities 200.3 279.9 147.7

2024 COMPARED TO 2023. The significant factors contributing to the $51.1 million decrease at NW Natural cash flow provided by operating activities were as follows:

•$64.8 million decrease in accounts receivable due to comparatively warmer weather in the current year;

•$20.5 million increase in contributions to our defined benefit pension plan;

•$18.4 million increase in asset optimization revenue sharing bill credits to customers; and

•$15.7 million decrease in net income; partially offset by

•$22.8 million decrease in accounts payable resulting from payments of higher priced gas in the prior year;

•$21.6 million decrease in inventories due to higher priced gas and more gas withdrawn from storage in the prior year; and

•$16.6 million increase in the decoupling mechanism primarily due to lower usage driven by comparatively warmer weather.

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The $79.7 million decrease in cash provided by operating activities at NW Holdings was primarily driven by the factors discussed above. In addition, Ohio Renewables paid $51.4 million to a subsidiary of EDL in connection with two RNG facilities.

2023 COMPARED TO 2022. The significant factors contributing to the $136.7 million increase at NW Natural cash flow provided by operating activities were as follows:

•$126.6 million decrease in accounts receivable due to colder weather in December 2022;

•$40.0 million decrease in net deferred gas costs due to the recovery of higher priced gas in 2022;

•$30.6 million decrease in asset optimization revenue sharing bill credits; and

•$19.9 million increase due to a compliance obligation related to the Washington CCA; partially offset by

•$64.9 million decrease in accounts payable resulting from payments of higher priced gas purchased in December 2022; and

•$22.3 million decrease in the decoupling mechanism.

The $132.3 million increase in cash provided by operating activities at NW Holdings was primarily driven by the factors discussed above.

NW Natural made $20.5 million of cash contributions to its qualified defined benefit pension plans during the year ended December 31, 2024 and no cash contributions during the year ended December 31, 2023. The American Rescue Plan, which was signed into law on March 11, 2021, includes a provision for pension relief that extends the amortization period for required contributions from 7 to 15 years and provides for the stabilization of interest rates used to calculate future required contributions. The amount and timing of future contributions will depend on market interest rates and investment returns on the plans’ assets. See Note 10.

NW Holdings and NW Natural have lease and purchase commitments relating to our operating activities that are financed with cash flows from operations. For information on cash flow requirements related to leases and other purchase commitments, see Note 7 and Note 16.

Investing Activities

NW Natural cash used in investing activities $ (357.6) $ (290.5) $ (320.3)

NW Holdings cash used in investing activities (429.0) (335.5) (435.5)

2024 COMPARED TO 2023. Cash used in investing activities increased $67.2 million at NW Natural and $93.5 million at NW Holdings, respectively. The increase at NW Natural and NW Holdings is primarily driven by higher capital expenditures as we continue to invest in our natural gas, water and wastewater utility systems. In addition, NWN Water completed the acquisition of Infrastructure Capital Holdings in 2024 and paid $29.9 million in cash consideration.

2023 COMPARED TO 2022. Cash used in investing activities decreased $29.8 million at NW Natural and $100.0 million at NW Holdings, respectively. The decrease at NW Natural is primarily driven by a decrease in capital expenditures related to two significant information technology projects that were placed into service in the prior year.

The decrease in cash used in investing activities at NW Holdings is driven by lower capital expenditures at NW Natural and less cash used for water and wastewater acquisitions.

NW Holdings capital expenditures for 2025 are expected to be in the range of $450 million to $500 million and for the six-year period from 2025 to 2030 are expected to range from $2.5 billion to $2.7 billion. NW Natural capital expenditures for 2025 are expected to be in the range of $330 million to $360 million and for the six-year period from 2025 to 2030 are expected to be approximately 70% of NW Holdings expected cap-ex range. SiEnergy capital expenditures for 2025 are expected to be in the range of $65 million to $75 million. NW Natural Water capital expenditures for 2025 are expected to be in the range of $55 million to $65 million.

The timing and amount of the core capital expenditures and projects for 2025 and the next six years could change based on regulation, growth, and cost estimates. Additional investments in our infrastructure during and after 2025 that are not incorporated in the estimates provided above will depend largely on additional regulations, growth, and expansion opportunities. Required funds for the investments are expected to be internally generated or financed with long-term debt or equity, as appropriate.

Financing Activities

NW Natural cash provided by financing activities $ 119.8 $ 20.4 $ 178.9

NW Holdings cash provided by financing activities 227.1 64.2 301.6

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2024 COMPARED TO 2023. Cash provided by financing activities increased $99.4 million at NW Natural primarily driven by higher short-term debt borrowings, lower long-term debt maturities and higher cash contributions from NW Holdings, partially offset by lower long-term debt issuances.

Cash provided by financing activities increased $162.9 million at NW Holdings primarily driven by higher short-term debt borrowings and higher proceeds from common stock issuances, partially offset by higher long-term debt maturities and lower long-term debt issuances.

2023 COMPARED TO 2022. Cash provided by financing activities decreased $158.5 million at NW Natural attributable to lower cash contributions from NW Holdings and the retirement of short and long-term debt, partially offset by an increase in long-term debt issuances.

Cash provided by financing activities decreased $237.4 million at NW Holdings attributable to lower proceeds from common stock issuances and the retirement of short and long-term debt, partially offset by an increase in long-term debt issuances.

Pension Cost and Funding Status of Qualified Retirement Plans

NW Natural's pension costs are determined in accordance with accounting standards for compensation and retirement benefits. See “Application of Critical Accounting Policies and Estimates – Pensions and Postretirement Benefits” below. Pension expense for NW Natural's qualified defined benefit plan, which is allocated between operations and maintenance expenses and capital expenditures, totaled $4.1 million in 2024, a change of $6.5 million from 2023. The fair market value of pension assets in this plan increased to $284.1 million at December 31, 2024 from $283.4 million at December 31, 2023. The increase was due to an increase in employer contributions of $20.5 millionand a gain on plan assets of $4.9 million, partially offset by benefit payments of $24.6 million.

Contributions made to NW Natural's company-sponsored qualified defined benefit pension plan are based on actuarial assumptions and estimates, tax regulations, and funding requirements under federal law. The qualified defined benefit pension plan was underfunded by $88.7 million at December 31, 2024. The American Rescue Plan, which was signed into law on March 11, 2021, includes a provision for pension relief that extends the amortization period for required contributions from 7 to 15 years and provides for the stabilization of interest rates used to calculate future required contributions. As a result, NW Natural did not make any plan contributions during 2023. NW Natural made $20.5 million of cash contributions to its qualified defined benefit pension plans during the year ended December 31, 2024. The amount and timing of future contributions will depend on market interest rates and investment returns on the plan's assets. See Note 10 for information regarding employer contributions and estimated future benefit payments and other pension disclosures.

Contingent Liabilities

Loss contingencies are recorded as liabilities when it is probable that a liability has been incurred and the amount of the loss is reasonably estimable in accordance with accounting standards for contingencies. See “Application of Critical Accounting Policies and Estimates—Environmental Contingencies” below. At December 31, 2024, NW Natural's total estimated liability related to environmental sites was $160.0 million. See Note 17 and "Results of Operations—Regulatory Matters—Rate Mechanisms—Environmental Cost Deferral and Recovery" above.

New Accounting Pronouncements

For a description of recent accounting pronouncements that may have an impact on our financial condition, results of operations, or cash flows, see Note 2.

APPLICATION OF CRITICAL ACCOUNTING POLICIES AND ESTIMATES

In preparing financial statements in accordance with U.S. GAAP, management exercises judgment to assess the potential outcomes and related accounting impacts in the selection and application of accounting principles, including making estimates and assumptions that affect reported amounts of assets, liabilities, revenues, expenses, and related disclosures in the financial statements. Management considers critical accounting policies to be those which are most important to the representation of financial condition and results of operations and which require management’s most difficult and subjective or complex judgments, including accounting estimates that could result in materially different amounts if reported under different conditions or used different assumptions. Our most critical estimates and judgments for both NW Holdings and NW Natural include accounting for:

•regulatory accounting;

•revenue recognition;

•derivative instruments and hedging activities;

•pensions and postretirement benefits;

•income taxes;

•environmental contingencies; and

•impairment of long-lived assets and goodwill.

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Management has discussed its current estimates and judgments used in the application of critical accounting policies with the Audit Committees of the Boards of NW Holdings and NW Natural. Within the context of critical accounting policies and estimates, management is not aware of any reasonably likely events or circumstances that would result in materially different amounts being reported.

Regulatory Accounting

The NGD segment is regulated by the OPUC and WUTC, which establish the rates designed to recover specific costs of providing regulatory services, and, to a certain extent, set forth special accounting treatment for certain regulatory transactions for which NW Natural records regulatory assets and liabilities. In general, the same accounting principles as non-regulated companies reporting under U.S. GAAP are used. However, authoritative guidance for regulated operations (regulatory accounting) requires different accounting treatment for regulated companies to show the effects of such regulation. For example, NW Natural accounts for the cost of gas using a PGA deferral and cost recovery mechanism, which is submitted for approval annually to the OPUC and WUTC. See "Results of Operations—Regulatory Matters—Rate Mechanisms—Purchased Gas Adjustment" above. There are other expenses and revenues that the OPUC or WUTC may require NW Natural to defer for recovery or refund in future periods. Regulatory accounting requires NW Natural to account for these types of deferred expenses (or deferred revenues) as regulatory assets (or regulatory liabilities) on the balance sheet. When the recovery of these regulatory assets from, or refund of regulatory liabilities to, customers is approved, NW Natural recognizes the expense or revenue on the income statement at the same time the adjustment to amounts is included in rates charged to customers.

The conditions that must be satisfied to adopt the accounting policies and practices of regulatory accounting include:

•an independent regulator sets rates;

•the regulator sets the rates to cover specific costs of delivering service; and

•the service territory lacks competitive pressures to reduce rates below the rates set by the regulator.

Because NW Natural's NGD operations satisfy all three conditions, NW Natural continues to apply regulatory accounting to NGD operations. Future accounting changes, regulatory changes, or changes in the competitive environment could require NW Natural to discontinue the application of regulatory accounting for some or all of our regulated businesses. This would require the write-off of those regulatory assets and liabilities that would no longer be probable of recovery from or refund to customers.

Based on current accounting and regulatory competitive conditions, NW Natural believes it is reasonable to expect continued application of regulatory accounting for NGD activities. Further, it is reasonable to expect the recovery or refund of NW Natural's regulatory assets and liabilities at December 31, 2024 through future customer rates. If it is determined that all or a portion of these regulatory assets or liabilities no longer meet the criteria for continued application of regulatory accounting, then NW Natural would be required to write-off the net unrecoverable balances against earnings in the period such determination is made. The net balance in regulatory asset and liability accounts was a net liability of $333.4 millionand a net liability of $268.2 million as ofDecember 31, 2024 and 2023, respectively. See Note 2 for more detail on regulatory balances.

Revenue Recognition

Revenues, which are derived primarily from the sale, transportation, and storage of natural gas, are recognized upon the delivery of gas commodity or services rendered to customers.

Accrued Unbilled Revenue

For a description of the policy regarding accrued unbilled revenue, most of which relates to the NGD business at NW Natural, see Note 2. The following table presents changes in key metrics if the estimated percentage of unbilled volume at December 31 was adjusted up or down by 1%:

In millions Up 1% Down 1%

Unbilled revenue increase (decrease)(1) $ 1.4 $ (1.4)

Margin increase (decrease)(1) 0.2 (0.2)

Net income before tax increase (decrease)(1) 0.1 (0.1)

(1) Includes impact of regulatory mechanisms including decoupling mechanism and excludes the impact of unbilled revenue from water services.

Derivative Instruments and Hedging Activities

NW Holdings and NW Natural have financial derivative policies that set forth guidelines for using financial derivative instruments to support prudent risk management strategies. These policies specifically prohibit the use of derivatives for speculative purposes. Financial derivative contracts are utilized to hedge most of our natural gas sale requirements. These contracts include swaps, options, and combinations of option contracts. NW Natural primarily uses these derivative financial instruments to manage commodity price variability. A small portion of NW Natural's derivative hedging strategy involves foreign currency exchange contracts.

Derivative instruments are recorded on the balance sheet at fair value. If certain regulatory conditions are met, then the derivative instrument fair value is recorded together with an offsetting entry to a regulatory asset or liability account pursuant to

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regulatory accounting, and no unrealized gain or loss is recognized in current income or loss. See "Regulatory Accounting" above for additional information. The gain or loss from the fair value of a derivative instrument subject to regulatory deferral is included in the recovery from, or refund to, NGD business customers in future periods. If a derivative contract is not subject to regulatory deferral, then the accounting treatment for unrealized gains and losses is recorded in accordance with accounting standards for derivatives and hedging which is either in current income or loss or in accumulated other comprehensive income or loss (AOCI or AOCL). Derivative contracts outstanding at December 31, 2024, 2023 and 2022 were measured at fair value using models or other market accepted valuation methodologies derived from observable market data. Estimates of fair value may change significantly from period-to-period depending on market conditions, notional amounts, and prices. These changes may have an impact on results of operations, but the impact would generally be mitigated due to the majority of derivative activities being subject to regulatory deferral treatment. For more information on derivative activity and associated regulatory treatment, see Note 2 and Note 15.

The following table summarizes the amount of gains (losses) realized from commodity price transactions for the last three years:

NGD business net gain (loss) on commodity swaps $ (119.2) $ 125.5 $ 107.8

Realized gains and losses from commodity hedges shown above were recorded in cost of gas and were, or will be, included in annual PGA rates.

NWN Water also used financial derivatives to hedge interest rate risk in the form of a pay-fixed interest rate swap. Unrealized gains and losses related to the interest rate swap agreement qualifies for cash flow hedge accounting and are recorded in AOCI on the consolidated balance sheet.

Pensions and Postretirement Benefits

NW Natural maintains a qualified non-contributory defined benefit pension plan, non-qualified supplemental pension plans for eligible executive officers and certain key employees, and other postretirement employee benefit plans covering certain non-union employees. NW Natural also has a qualified defined contribution plan (Retirement K Savings Plan) for all eligible employees. Only the qualified defined benefit pension plan and Retirement K Savings Plan have plan assets, which are held in qualified trusts to fund the respective retirement benefits. The qualified defined benefit retirement plan for union and non-union employees was closed to new participants several years ago. Non-union and union employees hired or re-hired after December 31, 2006 and 2009, respectively, and employees of certain NW Holdings subsidiaries are provided an enhanced Retirement K Savings Plan benefit. The postretirement Welfare Benefit Plan for non-union employees was also closed to new participants several years ago.

Net periodic pension and postretirement benefit costs (retirement benefit costs) and projected benefit obligations (benefit obligations) are determined using a number of key assumptions, including discount rates, rate of compensation increases, retirement ages, mortality rates and an expected long-term return on plan assets. See Note 10.

The vested benefit obligation for the defined benefit pension plan is the actuarial present value of the vested benefits to which the employee is entitled based on the employee's expected date of separation or retirement based on valuation assumptions.

Accounting standards also require balance sheet recognition of unamortized actuarial gains and losses and prior service costs in AOCI or AOCL, net of tax. However, the retirement benefit costs related to qualified defined benefit pension and postretirement benefit plans are generally recovered in rates charged to NGD customers, which are set based on accounting standards for pensions and postretirement benefit expenses. As such, NW Natural received approval from the OPUC to recognize the unamortized actuarial gains and losses and prior service costs as a regulatory asset or regulatory liability based on expected rate recovery, rather than including it as AOCI or AOCL under common equity. See "Regulatory Accounting" above and Note 2, "Industry Regulation."

A number of factors, as discussed above, are considered in developing pension and postretirement benefit assumptions. For the December 31, 2024 measurement date, NW Natural reviewed and updated:

•the weighted-average discount rate assumptions for pensions increased from 4.98% for 2023 to 5.56% for 2024, and the weighted-average discount rate assumptions for other postretirement benefits increased from 4.98% for 2023 to 5.53% for 2024. The new rate assumptions were determined for each plan based on a matching of benchmark interest rates to the estimated cash flows, which reflect the timing and amount of future benefit payments. Benchmark interest rates are drawn from the FTSE Above Median Curve, which consists of high quality bonds rated AA- or higher by S&P or Aa3 or higher by Moody’s;

•the expected annual rate of future compensation is separately determined for bargaining unit and non-bargaining unit employees. The rate assumption ranges from 4.8% to 5.1% in 2025 and thereafter;

•the expected long-term return on qualified defined benefit plan assets remained the same at 7.50% in 2023 and 2024; and

•other key assumptions, which were based on actual plan experience and actuarial recommendations.

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At December 31, 2024, the net pension liability (benefit obligations less market value of plan assets) for the defined benefit pension plan decreased $20.5 million compared to 2023. The decrease in the net pension liability is primarily due to the $19.8 million decrease to the pension benefit obligation and the $0.7 million increase in plan assets. The liability for non-qualified plans decreased $0.1 million and the liability for other postretirement benefits increased $0.6 million in 2024.

The expected long-term rate of return on assets is based on a forward-looking capital markets model along with the defined benefit pension plan current and target asset allocation. The model inputs are based on future expected long-term total returns and historical volatilities for various asset classes, along with their historical correlations. The model considers current investment-grade yields for fixed income investments, and the same plus a risk premium for riskier assets such as common stocks.

NW Natural believes its pension assumptions are appropriate based on plan design and an assessment of market conditions. The following shows the sensitivity of retirement benefit costs and benefit obligations to changes in certain actuarial assumptions:

Discount rate: (0.25) %

Qualified defined benefit plans $ 1.1 $ 9.7

Non-qualified plans — 0.1

Other postretirement benefits — 0.5

Expected long-term return on plan assets: (0.25) %

Qualified defined benefit plans 0.8 N/A

Income Taxes

Valuation Allowances

Deferred tax assets are recognized to the extent that these assets are believed to be more likely than not to be realized. In making such a determination, available positive and negative evidence is considered, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. NW Holdings and NW Natural have determined that all recorded deferred tax assets are more likely than not to be realized as of December 31, 2024. See Note 11.

Uncertain Tax Benefits

The calculation of tax liabilities involves dealing with uncertainties in the application of complex tax laws and regulations in the jurisdictions in which we operate. A tax benefit from a material uncertain tax position will only be recognized when it is more likely than not that the position, or some portion thereof, will be sustained upon examination, including resolution of any related appeals or litigation processes, on the basis of the technical merits. NW Holdings and NW Natural participate in the Compliance Assurance Process (CAP) with the Internal Revenue Service (IRS). Under the CAP program companies work with the IRS to identify and resolve material tax matters before the federal income tax return is filed each year. No reserves for uncertain tax benefits were recorded during 2024, 2023, or 2022. See Note 11.

Tax Legislation

When significant proposed or enacted changes in income tax rules occur, we consider whether there may be a material impact to our financial position, results of operations, cash flows, or whether the changes could materially affect existing assumptions used in making estimates of tax related balances.

The final tangible property regulations applicable to all taxpayers were issued on September 13, 2013 and were generally effective for taxable years beginning on or after January 1, 2014. In April 2023, the IRS published Revenue Procedure 2023-15 that provides a safe harbor method of income tax accounting for determining when expenditures for natural gas transmission and distribution property must be capitalized or are allowable as repair deductions. We have evaluated this new safe harbor and do not believe that the safe harbor method is materially different from NW Natural’s current repairs methodology or that this additional guidance would have a material effect on our financial condition and results of operations.

Regulatory Matters

Regulatory tax assets and liabilities are recorded to the extent it is probable they will be recoverable from, or refunded to, customers in the future. At December 31, 2024 and 2023, NW Natural had net regulatory income tax assets of $5.8 million and $8.0 million, respectively, representing future rate recovery of deferred tax liabilities resulting from differences in NGD plant financial statement and tax bases and NGD plant removal costs. These regulatory assets are currently being recovered through customer rates. At December 31, 2024 and 2023, regulatory income tax assets of $6.0 million and $4.9 million, respectively, were recorded by NW Natural, representing future rate recovery of deferred tax liabilities resulting from the equity portion of AFUDC. These regulatory assets are currently being recovered through customer rates.

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At December 31, 2024 and 2023, regulatory liability balances, representing the estimated net benefit to NGD customers resulting from the change in deferred taxes as a result of the Tax Cut and Jobs Act (TCJA), of $169.5 million and $174.2 million, respectively, were recorded by NW Natural. These balances include a gross up for income taxes of $44.9 million and $46.1 million, respectively. These regulatory liabilities are currently being amortized as a reduction in customer rates.

Environmental Contingencies

Environmental liabilities are accounted for in accordance with accounting standards under the loss contingency guidance when it is probable that a liability has been incurred and the amount of the loss is reasonably estimable. Amounts recorded for environmental contingencies take numerous factors into consideration, including, among other variables, changes in enacted laws, regulatory orders, estimated remediation costs, interest rates, insurance proceeds, participation by other parties, timing of payments, and the input of legal counsel and third-party experts. Accordingly, changes in any of these variables or other factual circumstances could have a material impact on the amounts recorded for our environmental liabilities. For a complete discussion of environmental accounting policies refer to Note 2. For a discussion of current environmental sites and liabilities refer to Note 17. In addition, for information regarding the regulatory treatment of these costs and NW Natural's regulatory recovery mechanism, see "Results of Operations—Regulatory Matters—Rate Mechanisms—Environmental Cost Deferral and Recovery" above.

Impairment of Long-Lived Assets and Goodwill

Long-Lived Assets

We review the carrying value of long-lived assets whenever events or changes in circumstances indicate the carrying amount of the assets might not be recoverable. Factors that would necessitate an impairment assessment of long-lived assets include a significant adverse change in the extent or manner in which the asset is used, a significant adverse change in legal factors or business climate that could affect the value of the asset, or a significant decline in the observable market value or expected future cash flows of the asset, among others.

When such factors are present, we assess the recoverability by determining whether the carrying value of the asset will be recovered through expected future cash flows. An asset is determined to be impaired when the carrying value of the asset exceeds the expected undiscounted future cash flows from the use and eventual disposition of the asset. If an impairment is indicated, we record an impairment loss for the difference between the carrying value and the fair value of the long-lived assets. Fair value is estimated using appropriate valuation methodologies, which may include an estimate of discounted cash flows.

Goodwill and Business Combinations

In a business combination, goodwill is initially measured as any excess of the acquisition-date fair value of the consideration transferred over the acquisition-date fair value of the net identifiable assets acquired.

The carrying value of goodwill is reviewed annually during the fourth quarter, or whenever events or changes in circumstance indicate that such carrying values may not be recoverable.

NW Holdings' policy for goodwill assessments begins with a qualitative analysis in which events and circumstances are evaluated, including macroeconomic conditions, industry and market conditions, regulatory environments, and the overall financial performance of the reporting unit. If the qualitative assessment indicates that the carrying value may be at risk of recoverability, a quantitative evaluation is performed to measure the carrying value against the fair value of the reporting unit. This evaluation may involve the assessment of future cash flows and other subjective factors for which uncertainty exists and could impact the estimation of future cash flows. These factors include, but are not limited to, the amount and timing of future cash flows, future growth rates, and the discount rate. Unforeseen events and changes in circumstances or market conditions could adversely affect these estimates, which could result in an impairment charge. A qualitative assessment was performed during the fourth quarter of 2024 which indicated a quantitative assessment was not required; thus, no goodwill impairment was recorded. See Note 2 and Note 14 for additional information.