Atmos Energy Corporation (ATO)
Atmos Energy is one of the largest US natural-gas distributors, serving customers across several states.
ATO vs WEC: how the two businesses compare
- Bigger business: WEC, with $9.8B of yearly revenue, about 2.1× ATO's $4.7B.
- More cash from each sale: ATO turns 44 cents of each sales dollar into operating cash flow, against 34 cents at WEC.
From each company's latest annual SEC filing. Fiscal years can end on different dates.
WEC Energy (WEC) is the larger business by reported revenue: $9.8B in its fiscal year ended Dec 2025, about 2.1× ATO's $4.7B (fiscal year ended Sep 2025). The SEC places them in related industries (Natural Gas Distribution; Electric & Other Services Combined), and both map to the Rates & central banks research theme.
Figures come from each company's own SEC filings. This page compares the businesses; it is not a price target or a verdict.
- Utilities
- Different
- Separate classifications
- Different
- ATO September 30 · WEC December 31
- Feb 20, 2026
ATO vs WEC: quick comparison
| Company fact | ATO | WEC |
|---|---|---|
| Company | Atmos Energy Corporation | WEC Energy Group, Inc. |
| Exchange | NYSE | NYSE |
| SEC industry | Natural Gas Distribution | Electric & Other Services Combined |
| Fiscal year-end | September 30 | December 31 |
| Latest annual filing | 10-K · 2025-11-14 | 10-K · 2026-02-20 |
ATO vs WEC: audited financials
- Scale: WEC's $9.8B of revenue is about 2.1× ATO's $4.7B.
- Cash conversion: operating cash flow equalled ATO 43.6% of revenue, or 1.71× net income; WEC 34.5% of revenue. A ratio well above 1× usually reflects non-cash charges or working-capital release; well below 1× can reflect working-capital build or non-cash gains.
- Periods: the fiscal years end about 3 months apart (2025-09-30 for ATO, 2025-12-31 for WEC), so each figure reflects somewhat different demand and cost conditions.
| Metric | ATO | WEC |
|---|---|---|
| Revenue | $4.7B2024-10-01 to 2025-09-30 · SEC filing | $9.8B2025-01-01 to 2025-12-31 · SEC filing |
| Net income | $1.2B2024-10-01 to 2025-09-30 · SEC filing | — |
| Operating cash flow | $2.0B2024-10-01 to 2025-09-30 · SEC filing | $3.4B2025-01-01 to 2025-12-31 · SEC filing |
| Diluted EPS | $7.462024-10-01 to 2025-09-30 · SEC filing | $4.812025-01-01 to 2025-12-31 · SEC filing |
| Net margin | 25.5%2024-10-01 to 2025-09-30 · SEC filing | — |
ATO: FY ending 2025-09-30 · WEC: FY ending 2025-12-31. Figures as tagged in each issuer's SEC XBRL filing; fiscal calendars may not align.
Where ATO and WEC overlap, and where they don't
Overlap
- Related SEC industries: both sit in SIC major group 49.
- Shared research theme: Rates & central banks.
Differences
- Different four-digit SIC codes: ATO is 4924 (Natural Gas Distribution); WEC is 4931 (Electric & Other Services Combined).
- Offset fiscal calendars: ATO's year ends September 30 and WEC's December 31, about 3 months apart.
- Scale: WEC reported about 2.1× the annual revenue of ATO.
Overlap is drawn from SEC classifications and Yield Theory research themes. It is not evidence that the companies sell to the same customers or compete product for product.
WEC Energy Group, Inc. (WEC)
WEC Energy Group provides regulated electricity and natural gas across the upper Midwest.
What moves each company
Company-specific drivers maintained by Yield Theory. Use them to decide which filing deserves deeper work; they are not predictions.
What moves ATO
We have not yet published a company-specific driver list for ATO. The primary source is Item 1 (Business) and Item 1A (Risk Factors) of its 10-K filed 2025-11-14.
What moves WEC
We have not yet published a company-specific driver list for WEC. The primary source is Item 1 (Business) and Item 1A (Risk Factors) of its 10-K filed 2026-02-20.
The investment question
You now know WEC reports about 2.1× ATO's revenue. Those are the facts. The investment question is what each share price already assumes about their exposure to rates & central banks, and which evidence in the next filings would prove that assumption wrong.
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Read the full researchSEC filing comparison and disclosure evidence
Start with primary filings because fiscal calendars and accounting presentation can make superficially similar quarters incomparable. ATO's fiscal year ends September 30, while WEC's ends December 31. Normalize the reporting periods before comparing growth, margins, capital intensity, or guidance.
The current verified House and Senate snapshot contains 5 matched transaction rows for ATO and 5 matched transaction rows for WEC. These delayed, range-based disclosures can identify a filing to inspect; they do not establish motive, conviction, or a real-time trading signal.
ATO primary filings
WEC primary filings
What this comparison cannot tell you
This page does not contain licensed live prices, a valuation model, earnings estimates, portfolio constraints, or a forecast of future returns. SEC classifications can be broad, company descriptions can lag strategic change, and the latest annual filing may predate a material acquisition or divestiture. Read subsequent quarterly and current reports before making a decision.
A stronger business is not automatically the better stock. Starting valuation, expectations, capital structure, cyclicality, dilution, and the probability of each thesis determine the investment outcome. Use this comparison to frame the work, then verify the numbers in the linked filings and current company disclosures.
More comparisons involving ATO or WEC
ATO vs WEC FAQs
Are ATO and WEC direct competitors?
Not necessarily. Atmos Energy files as Natural Gas Distribution and WEC Energy as Electric & Other Services Combined. The pair is compared because both map to the Rates & central banks research theme, not because the filings show head-to-head competition.
Is ATO or WEC the bigger company by revenue?
WEC Energy (WEC) is the larger business by reported revenue: $9.8B in its fiscal year ended Dec 2025, about 2.1× ATO's $4.7B (fiscal year ended Sep 2025). The SEC places them in related industries (Natural Gas Distribution; Electric & Other Services Combined), and both map to the Rates & central banks research theme. Each figure is the annual amount tagged in the company's own SEC XBRL filing; market value depends on live prices, which this page does not publish.
Which is better, ATO or WEC?
There is no context-free winner. Compare the operating exposures, filing evidence, valuation, balance sheet, and risks against the specific thesis you are testing. This page deliberately does not turn a static profile into a buy or sell recommendation.
Does this ATO vs WEC comparison include live prices?
No. Yield Theory does not republish unlicensed real-time market data. The financial figures on this page are the audited annual numbers Atmos Energy Corporation and WEC Energy Group, Inc. tagged in their SEC XBRL filings. Use a regulated broker or licensed quote provider for current prices and valuation multiples.
Where does the company information come from?
Company classifications, fiscal year-ends, and filing links come from the SEC EDGAR submissions API snapshot refreshed 2026-11-10. Business summaries and research themes are maintained by Yield Theory.
Data snapshot: SEC EDGAR submissions API, refreshed 2026-11-10. Independent educational research; not investment advice.
Which business differences matter to the investment thesis?
ATO vs WEC compares reported results. The reports below show how we connect operating evidence to an investment thesis, its assumptions, catalysts, and risks. $39/month or $249/year.
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