One Gas, Inc. · NYSE:OGS
One Gas — Mizuho Power, Energy and Infrastructure Conference (December 2025)
43 slides from One Gas's conference presentation, December 2025
Slide 1: Investor Update
Investor Update December 2025
Slide 2: About Us
71% market share, the largest in Kansas About Us 89% market ONE Gas, Inc. (NYSE: OGS) is a 100-percent regulated share, the largest natural gas utility and is one of the largest natural gas in Oklahoma utilities in the United States. ONE Gas provides natural gas distribution services 13% market shar
Slide 3: Recent Highlights
Recent Highlights Creating Value for a Better Tomorrow 2026 EPS guidance of We estimate $800 Replaced over 450 miles $4.65 – $4.77 & 2026-30 million in 2026 capital of transmission, main EPS growth of 5 – 7%* investments and service lines in 2024 ~23,000 new meter sets Increased storage to ~61 8th c
Slide 4: Our Strategy
Our Strategy
Slide 5: Distinct Advantages Driving Sustained Growth
Distinct Advantages Driving Sustained Growth Delivering consistent value through strategic investment and financial discipline Favorable regional dynamics with strong in-migration, robust economic development and supportive regulatory frameworks across our service territories Attainable growth plans
Slide 6: Regional Strengths Propel Sustainable Growth
Regional Strengths Propel Sustainable Growth Increased demand and support for natural gas provide expansion opportunities Natural gas is a core energy resource, backed by energy choice legislation in all jurisdictions o ~30% of U.S. natural gas produced in Texas and Robust economic growth drives res
Slide 7: Expanding Capacity, Enhancing Affordability
Expanding Capacity, Enhancing Affordability Building a solid foundation for sustainable growth Improved processes and workforce investments increase operating efficiency, capacity and capabilities Managing expenses and increasing efficiency help maintain customer affordability Investment in workforc
Slide 8: Approved Capital Structures Support a Strong Balance Sheet
Approved Capital Structures Support a Strong Balance Sheet REGULATORY FRAMEWORK LIQUIDITY PROFILE3 $1,000M $226.3M $961.9M LDC Equity Ratio Allowed ROE $900M 1 1 KGS 60.2% 9.5% $800M $150.0M ONG 58.5% 9.4% $700M TGS 59.9% 2 9.8% 2 $585.6M $600M $500M BALANCE SHEET STRENGTH $400M • Expect adjusted CF
Slide 9: Financial Outlook
Financial Outlook
Slide 10: 2026 Guidance Summary
2026 Guidance Summary1 Creating long-term value and serving a growing and dynamic customer base EARNINGS OUTLOOK • Net income for 2026 in a range of $294 - $302 million • EPS range of $4.65 - $4.77 per diluted share • Assumes ~63.4 million diluted shares outstanding • CAPITAL INVESTMENTS • 2026 capi
Slide 11: Financing Requirements and Activities
Financing Requirements and Activities Investing in growth while maintaining a strong balance sheet 2026 dividends and capital investments primarily funded by cash flow from operations of approximately $650-$700 million1 • Expected 2026 short- and long-term net financing need of $250-$300 million ~$1
Slide 12: Five-Year Financial Highlights
Five-Year Financial Highlights Building sustainable long-term value CAPITAL INVESTMENTS & RATE BASE SUSTAINABLE ANNUAL GROWTH RATES • Capital investments of ~$4.3 billion • Based on updated 2025 Net Income and EPS ̶ ~$2.5 billion investment in system integrity and midpoints of $264 million and $4.37
Slide 13: Long-Term EPS Performance & Outlook
Long-Term EPS Performance & Outlook EPS CAGR 5 - 7% $6.00 EPS CAGRs $5.85 2 5-Year Forecast (2025-2030 ) 6.0% $5.50 10-Year (2014-2024) 6.6% 1 $5.00 10-Year (2015-2025G ) 6.9% 1 $4.71 10-Year (2016-2026G ) 5.9% $4.50 $4.37 $4.08 $4.14 $3.85 $3.91 $4.00 $3.68 $3.51 $3.50 $3.25 $3.08 $3.00 $2.65 $2.50
Slide 14: Balance Sheet Strength
Balance Sheet Strength Strong credit rating and financing flexibility RATING AGENCY RATING OUTLOOK LONG-TERM DEBT MATURITIES 1 (MILLIONS) Moody’s A3 Stable S&P A- Stable $600 $550 4.66% 5.10% $400 $300 $3001 REVOLVING CREDIT FACILITY $250 4.50% 2.00% 4.25% 4.96%2 • $1.5 billion limit 2025 2026 2029
Slide 15: Capital Investments
Capital Investments
Slide 16: Well-Defined Capital Investment Plan
Well-Defined Capital Investment Plan Investments ~3x depreciation CAPITAL INVESTMENTS 2026G CAPITAL INVESTMENTS (MILLIONS) BY STATE ~$800 (MILLIONS) $762 ~$750 $47 $729 $32 $31 $26 $658 $32 $178 $179 $228 $178 Kansas $177 $176 $552 $525 $540 $525 Texas $449 $313 $283 $295 Oklahoma $234 $255 $216 $31
Slide 17: Capital Investments
Capital Investments KANSAS OKLAHOMA TEXAS 2026G: 1.9X DEPRECIATION 2026G: 2.8X DEPRECIATION 2026G: 3.5X DEPRECIATION $306 $311 $311 $313 $286 $288 $287 $257 $256 $242 $185 $176 $159 $169 $151 (MILLIONS) $83 $90 $108 $112 $63 $71 $92 $93 $93 $100 $53 $75 $78 $84 $88 2022 2023 2024 2025G 2026G 2022 20
Slide 18: Rate Base
Rate Base AVERAGE RATE BASE* 2026G AVERAGE RATE BASE* (BILLIONS) BY STATE TOTAL: $6.3 BILLION $6.30 $5.52 $5.80 $5.15 $4.69 $1.49 billion $2.12 billion $2.69 billion 2022 2023 2024 2025G 2026G Kansas Oklahoma Texas * See Appendix for definition. ~9% growth expected in 2026 CAPITAL INVESTMENTS 18
Slide 19: Regulatory Update
Regulatory Update
Slide 20: Active Regulatory Calendar
Active Regulatory Calendar PROGRESS JURISDICTION RATES REQUESTED FILING DATE EQUITY RETURN ON (MILLIONS) RATIO EQUITY IN Texas – Rate Case1 $15.0 M Jun-2025 59.90% 9.8% APPROVED RATES EFFECTIVE EQUITY RETURN ON JURISDICTION (MILLIONS) DATE RATIO EQUITY Rio Grande Valley – GRIP $3.0 M Sep-2025 59.10%
Slide 21: Oklahoma Natural Gas
Oklahoma Natural Gas PBRC approved and effective June 2025 Performance-based rate change (PBRC) interim filing for annual rate reviews between full rate cases allows recovery of capital investments and operating expenses. 2025 PBRC Filing Incremental Revenue $41.1 million annual revenue increase app
Slide 22: Kansas Gas Service
Kansas Gas Service GSRS approved July; rates effective August 2025 Gas System Reliability Surcharge (GSRS) allows for recovery of investments in safety-related projects (includes physical and cyber security) and government-mandated relocations between rate cases 2025 GSRS FILING File GSRS Annually
Slide 23: Texas Gas Service
Texas Gas Service Consolidation rate case filed June; partial settlement reached; final decision on settlement and consolidation expected January 2026 1 2025 RATE CASE – PARTIAL SETTLEMENT ESTIMATED EFFECTIVE DATE Q1 2026 Incremental Revenue $15 million annual revenue increase Capital Expenditures $
Slide 24: Texas Gas Service
Texas Gas Service RGV GRIP approved August; rates effective September 2025 Gas Reliability Infrastructure Program (GRIP) allows for recovery of capital investments made between rate cases RIO GRANDE VALLEY 2025 GRIP FILING Incremental Surcharge $3.0 million annual revenue increase Revenue approved F
Slide 25: Texas Gas Service
Texas Gas Service West-North GRIP approved May; rates effective June 2025 Gas Reliability Infrastructure Program (GRIP) allows for recovery of capital investments made between rate cases WEST-NORTH 2025 GRIP FILING Incremental Surcharge $8.2 million annual revenue increase Revenue approved File GRIP
Slide 26: Texas Gas Service
Texas Gas Service Central-Gulf GRIP approved May; rates effective June 2025 Gas Reliability Infrastructure Program (GRIP) allows for recovery of capital investments made between rate cases CENTRAL-GULF 2025 GRIP FILING Incremental Surcharge $15.4 million annual revenue increase Revenue approved File
Slide 27: Customer Affordability
Customer Affordability G ONE Gas
Slide 28: 3-to-1 Average Advantage in ONE Gas Territories
3-to-1 Average Advantage in ONE Gas Territories 1 Natural gas price advantage over electricity KWH EQUIVALENT ELECTRICITY VS. NATURAL GAS 14.94¢ 14.22¢ 12.24¢ 2.3x advantage 2.7x advantage 3.2x advantage 6.49¢ 4.50¢ 4.40¢ Texas Oklahoma Kansas ² Avg. retail price of electricity/kWh ³ ONE Gas deliver
Slide 29: Affordability Anchored in Strategic Cost Management
Affordability Anchored in Strategic Cost Management Cash flow stability AVERAGE MONTHLY RESIDENTIAL CUSTOMER BILL • ~92% of customers are residential • ~70% of revenue less the cost of gas is $81 $77* $79* fixed charges $73* $60 $64* $58 $30 Focus remains on customer $50 $51 $55 $54 $50 $43 $33 $31
Slide 30: Delivering Foundational Energy
Delivering Foundational Energy
Slide 31: Reducing Emissions
Reducing Emissions Operating in an environmentally responsible manner Emissions Reduction Goal By 2035, we expect to achieve a 55% reduction in Scope 1 emissions due to leaks from mains and services, measured from a 2005 baseline and accounting for projected system growth. As of December 31, 2024, w
Slide 32: Emissions Reduction Strategy
Emissions Reduction Strategy Aligned with overall strategy Tightening our system • Pipeline replacement and protection replaces higher emitting pipe with lower-emitting pipe • Advanced leak detection reduces time leaks are active Reducing customer gas usage • Energy efficiency and customer education
Slide 33: ESG Ratings & Company Recognition
ESG Ratings & Company Recognition Robust Disclosures RATING ORGANIZATION 2024 2023 2022 • Full alignment with SASB • Following TCFD recommendations MSCI AAA AA AA • Disclosure of Scope 1 and 2 emissions Sustainalytics 25.8 28.6 30.9 Additional governance documents and reports ISS Corporate Rating C+
Slide 34: Appendix
Appendix
Slide 35: Sustainable Business Model
Sustainable Business Model Focused Business Capital Investment Regulatory Cash Flow Strategy Opportunities Construct Stability ▪ 100% regulated natural ▪ 20+ year vintage ▪ 3 states, multiple ▪ ~ 70% of fixed charges gas distribution utility pipeline replacement jurisdictions for recovery of revenue
Slide 36: Sustainable Business Model
Sustainable Business Model Customer Safe & Reliable Delivering Affordability Energy Foundational Energy ▪ Customer growth ▪ Industry-leading ▪ Committed helps moderate performance in to sustainability per-customer costs employee safety ▪ Energy efficiency and ▪ Leveraging technology ▪ Demonstrated s
Slide 37: Corporate Structure and State Figures
Corporate Structure and State Figures INCORPORATED ENTITY 100% regulated natural gas distribution No levered holding company; all debt issued by ONE Gas, Inc.1 Division capital structures match Corporate capital structure KEY FIGURES 2 Average Number of Customers 651,000 924,000 706,000 Distribution
Slide 38: Authorized Rate Base
Authorized Rate Base As of November 30, 2025 KANSAS OKLAHOMA TEXAS $2,453 $2,273 $2,067 (MILLIONS) $1,854 $1,895 $1,726 $1,720 $1,468 $1,528 $1,330 $1,412 $1,197 $1,261 $1,239 $1,336 2021 2022 2023 2024 2025 2021 2022 2023 2024 2025 2021 2022 2023 2024 2025 APPENDIX 38
Slide 39: Rate Base Definition
Rate Base Definition Authorized Rate Base $5.8 billion (as of November 30, 2025) • Includes capital investments authorized in most recent rate cases and interim filings • Excludes any capital investments since last approved rate cases or filings 2026 Estimated Average Rate Base $6.3 billion • Averag
Slide 40: Comprehensive Regulatory Mechanisms
Comprehensive Regulatory Mechanisms KEY MECHANISMS: KANSAS OKLAHOMA TEXAS Central-Gulf Nov. 2030 West-North Dec. 2028 General Rate Case Filing Deadline 2030 June 2027 Rio Grande Feb. 2030 Valley Interim capital recovery GSRS PBRC GRIP Weather normalization ✓ ✓ ✓ Purchased gas riders (including gas c
Slide 41: Regulatory Construct
Regulatory Construct Governance KANSAS OKLAHOMA TEXAS “Home Rule” with three jurisdictions; Kansas Corporation Commission Oklahoma Corporation Commission Texas Railroad Commission has appellate authority Appointed by the governor to four-year Railroad Commission elected to Elected to six-year stagge
Slide 42: Non-GAAP Reconciliation
Non-GAAP Reconciliation Cash flow from operations before changes in working capital (MILLIONS) 2026 GUIDANCE* Net income $ 299 Depreciation and amortization 306 Deferred taxes 51 Other 24 Cash flow from operations before changes in working capital $ 680 * Amounts shown are estimated midpoints as con
Slide 43: Investor Information
Investor Information Contact information and forward-looking statements Statements contained in this presentation that include or refer to Company expectations, our business outlook, our future plans or predictions relating to ONE Gas, Inc. any matters should be considered forward-looking statements
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