Largest Utility Companies in the US, 2025: Parent Companies Ranked by Customers, Sales and Revenue

Operating utility to parent company ledger, fiscal 2025

Checked Checked each year when EIA releases final EIA-861 data (October) and parents file 10-K reports (February to March). Last checked 2026-11-05. Entries are neutral records of public data; each links to its source record.

The largest utility companies in the US by customers: Exelon, Duke Energy and FirstEnergy

Rolled up to parent companies, three holding companies each serve more than 6 million electricity customers. Exelon leads with 9.31 million in 2025, although none of its six utilities is the largest single utility.

Exelon's 9.31 million customers in 2025 come from Commonwealth Edison in Illinois (4.16 million), PECO in Pennsylvania (1.71 million), Baltimore Gas and Electric, Pepco, Delmarva Power and Atlantic City Electric, according to Form EIA-861 2025 and the Exhibit 21 subsidiary list in Exelon's fiscal 2025 10-K.

Duke Energy follows with 8.63 million customers at six utilities in North Carolina, South Carolina, Florida, Indiana, Ohio and Kentucky. FirstEnergy is third with 6.28 million at seven utilities. NextEra Energy (6.01 million) and PG&E Corporation (5.73 million) each own one large utility.

No other parent in the top 20 has a partial stake in a retail utility it is credited with, based on a text search of the fiscal 2025 10-K reports. Outside the top 20, AES holds about 70% of AES Indiana and of AES Ohio, where CDPQ owns about 30%; AES's weighted count is 0.74 million against 1.06 million in full. Partial stakes in transmission companies (FirstEnergy Transmission, American Transmission Co) do not affect customer counts.

Customer (EIA-861): An electricity account at a metered location, not a person. In this ranking a utility's customers are its bundled-service accounts plus its delivery-only accounts, whose energy comes from a competitive supplier.

Duke Energy sells the most electricity and collects the most retail revenue

Ranked by volume or money, Duke Energy moves to first place: 218.3 TWh and $25.38 billion of retail electric revenue in 2025. Texas wires companies rank high on volume and low on revenue.

Duke Energy delivered 218.3 TWh to retail customers in 2025, ahead of Exelon (196.2 TWh) and American Electric Power (196.0 TWh). The 10 largest parents by volume delivered 39.5% of the 4,079.9 TWh sold to US retail customers in 2025 (EIA Electric Power Annual Table 2.2).

On retail electric revenue, Duke Energy ($25.38 billion), Exelon ($20.46 billion) and Southern Company ($19.32 billion) lead. Revenue per MWh separates the models: Sempra collected $48.17 per MWh because Oncor bills only delivery charges, while PG&E Corporation collected $254.30 per MWh.

Florida Power & Light is the biggest single electric company in the US

Among single operating companies, Florida Power & Light leads with 6.01 million customers, followed by Pacific Gas and Electric and Southern California Edison.

Florida Power & Light served 6.01 million customers in 2025, Pacific Gas and Electric 5.73 million and Southern California Edison 5.33 million. EIA reported 5.48 million for Pacific Gas and Electric and 5.07 million for Southern California Edison in 2017, on the same survey.

Oncor (4.08 million) and CenterPoint Energy Houston Electric (2.86 million) are delivery-only wires companies in the competitive Texas ERCOT market. EIA files them separately in Delivery_Companies_2025.xlsx; leaving that file out would drop more than 8 million Texas accounts from any utility ranking.

Public power and co-ops: Los Angeles DWP, Salt River Project and Pedernales lead their groups

No public power utility or co-op is as large as the 20 largest investor-owned parents, but the biggest are larger than many investor-owned utilities. They are ranked here by ownership type.

The Los Angeles Department of Water and Power was the largest municipal utility in 2025 with 1,516,453 customers, followed by CPS Energy of San Antonio (986,641) and Austin Energy (577,889). Salt River Project in Arizona was the largest political subdivision (1,188,189) and the Long Island Power Authority the largest state utility (1,166,171).

Pedernales Electric Cooperative in Texas was the largest co-op in 2025 with 474,954 customers, 42.3% more than the 333,809 EIA reported for 2017. Four of the 10 largest co-ops are in Florida and three in Georgia.

The Tennessee Valley Authority, the largest federal power entity, sold 22.5 TWh directly to 65 retail customers in 2025 and 146.4 TWh for resale, mostly to local public power and co-op distributors. Federal utilities are therefore ranked by sales, not customers.

Investor-owned utility (IOU): A shareholder-owned company, usually a subsidiary of a holding company, regulated by a state utility commission.

Cooperative (co-op): A not-for-profit utility owned by the members it serves, who elect its board. Most serve rural and suburban areas.

Public power: Utilities owned by a city (municipal), a public utility district or irrigation district (political subdivision), a state authority or the federal government.

The American Public Power Association says public power utilities serve more than 55 million Americans in 2,000 communities, about 1 in 7 electricity customers. The National Rural Electric Cooperative Association says co-ops serve 42 million people and power more than 23 million businesses, homes, schools and farms. These are association figures counting people, not EIA account counts.

The 10 largest parent companies serve 37.2% of US electricity customers

Ownership is concentrated at the holding-company level: the top 10 parents served 61.58 million of 165,488,106 US customers in 2025, and the top 20 served 56.5%.

Exelon alone held 5.6% of US customers in 2025. The top five held 21.7%, the top 10 37.2% and the top 20 56.5%. The denominator is EIA's count of 165,488,106 ultimate customers, which rose 1.1% from 163,741,126 in 2024. Weighted by ownership stakes, the top five held 21.6%, the top 10 36.6% and the top 20 56.0%; the top-10 gap of 0.6 percentage points comes almost entirely from Oncor.

The 2025 EIA-861 frame lists 3,026 electric utilities: 1,820 municipal, 861 cooperative, 174 investor-owned, 137 political subdivision, 24 state and 10 federal entities. EIA counted 168 investor-owned utilities, 1,958 publicly owned utilities and 812 co-ops for 2017; the 2025 frame holds 1,991 publicly owned entities and 861 co-ops, though the frame also includes some entities without retail customers.

Residential prices at the 20 largest utilities run from 13.43 to 37.52 cents per kWh

Average residential revenue per kWh at the 20 utilities with the most bundled residential customers spans 24.09 cents in 2025, and 12 of the 20 sit above the US average of 17.23 cents.

Duke Energy Carolinas had the lowest average at 13.43 cents per kWh in 2025, then PacifiCorp (14.42) and Florida Power & Light (14.62). The three highest were two California utilities and one New York utility: Pacific Gas and Electric 37.52 cents, Consolidated Edison 36.74 and Southern California Edison 31.48.

The bundled figure covers only customers who buy energy from the utility. Pacific Gas and Electric served 1,738,444 bundled residential customers out of 5,055,556 residential accounts in 2025 (34.4%); most of the rest buy energy from community choice aggregators. State-level prices and bills are covered in the average electric bill by state report; outage records by state are in power outages by state.

How the operating utilities map to their parent companies

The ledger below records, for each of the 94 operating utilities rolled up, the parent named in an SEC filing and the date of that filing.

Every roll-up rests on a filing opened on EDGAR: an Exhibit 21 subsidiary list, or the 10-K text where the parent files without one. 34 parents are mapped. Utilities whose parent files nothing with the SEC, such as Duquesne Light, El Paso Electric and Cleco Power, appear as stand-alone companies; none would reach the top 20. Avangrid filed Form 15 on January 2, 2025 and has filed no 10-K since fiscal 2023, so its mapping still rests on the fiscal 2023 Exhibit 21; archived copies of the NYSEG, RG&E, Central Maine Power and United Illuminating websites from October and November 2026 all carry the Avangrid name.

• NextEra Energy and Dominion Energy: merger agreement signed May 15, 2026; each Dominion share converts into 0.8138 NextEra shares plus a pro rata share of $360 million in cash; closing expected in the second half of 2027 (NextEra 8-K).
• AES Corporation (AES Indiana, AES Ohio): merger agreement with Horizon Parent, L.P., a consortium led by GIP and EQT Infrastructure VI, signed March 1, 2026, at $15.00 a share; pending regulatory approvals.
• TXNM Energy (PNM, TNMP): sale to Blackstone Infrastructure affiliates approved by Texas regulators on February 6, 2026 and FERC on February 20, 2026; New Mexico review continues.
• Duke Energy Florida: Brookfield bought 9.19% of parent Florida Progress on March 3, 2026, toward up to 19.7% by 2028.
• Emera (Tampa Electric): merger of equals with Canadian Utilities announced October 6, 2026; close expected in 2027.
• Xcel Energy: NSP-Wisconsin agreed to sell its Michigan electric assets to Upper Peninsula Power Company; close expected in 2027.
• None of these had closed by November 5, 2026, so the 2025 ranking uses the ownership in the fiscal 2025 filings.

For contractors, the parent matters for interconnection, line-extension and vendor rules, which are often set at holding-company level across several states. Contractor rankings are in largest electrical contractors, and business resources are in the business section.

Counts from the ledger

Get the calculations (CSV)

The numbers that matter

1. Exelon served 9.31 million electricity customers in 2025 through Commonwealth Edison, PECO, BGE, Pepco, Delmarva Power and Atlantic City Electric, the most of any US parent.^[1][10]
2. Duke Energy was second by customers with 8.63 million in 2025 across six operating utilities in six states.^[1][11]
3. FirstEnergy was third with 6.28 million customers in 2025 at seven utilities in Ohio, Pennsylvania, New Jersey, West Virginia, Maryland and New York.^[1][12][13]
4. Florida Power & Light, owned by NextEra Energy, was the largest single operating utility in 2025 with 6.01 million customers.^[1][14]
5. Duke Energy delivered 218.3 TWh to retail customers in 2025, 5.3% of US retail sales of 4,079.9 TWh.^[1][4][11]
6. Duke Energy also collected the most retail electric revenue in 2025, $25.38 billion, ahead of Exelon ($20.46 billion).^[1][11]
7. The 10 largest parents served 37.2% of US electricity customers in 2025 and delivered 39.5% of retail electricity (top 10 by MWh).^[1][3][4]
8. The largest parent, Exelon, held 5.6% of US customers in 2025; the five largest held 21.7%.^[1][3]
9. Investor-owned utilities served 71.6% of utility customers in 2025, close to the 72% EIA reported for 2017.^[1][7]
10. The 2025 EIA-861 frame lists 3,026 electric utilities: 1,820 municipal, 861 cooperative, 174 investor-owned, 137 political subdivision, 24 state and 10 federal.^[1]
11. Pedernales Electric Cooperative in Texas served 474,954 customers in 2025, 42.3% more than the 333,809 EIA reported for 2017.^[1][7]
12. Los Angeles Department of Water and Power (municipal, 1,516,453), Salt River Project (political subdivision, 1,188,189) and Long Island Power Authority (state, 1,166,171) were the largest public power utilities in 2025.^[1]
13. At the 20 largest utilities by residential customers, 12 had a 2025 bundled residential price above the US average of 17.23 cents per kWh.^[1][6]
14. Pacific Gas and Electric's bundled residential price was 37.52 cents per kWh in 2025, 2.8 times Duke Energy Carolinas' 13.43 cents.^[1]
15. Weighted by ownership stakes, Sempra's 2025 customer count falls from 5.63 million to 4.82 million and its rank from 7th to 8th, because it holds an indirect 80.25% of Oncor; Duke Energy's falls from 8.63 million to 8.44 million (80.1% of Duke Energy Indiana).^{[1][18][70][74]}
16. If the NextEra Energy and Dominion Energy merger signed on May 15, 2026 closes, the combined parent would have served 9.65 million customers in 2025, more than Exelon's 9.31 million; closing is expected in the second half of 2027.^[1][75][76]

In short

• Exelon was the largest US utility parent by customers in 2025, with 9.31 million accounts at six utilities led by Commonwealth Edison (4.16 million), per Form EIA-861 and Exelon's 10-K.
• Florida Power & Light was the largest single operating utility, with 6.01 million customers in Florida in 2025.
• Duke Energy led on volume and money: 218.3 TWh of retail sales and $25.38 billion of retail electric revenue in 2025.
• The 10 largest parents served 61.58 million customers, 37.2% of the 165,488,106 US total in 2025; the 20 largest served 56.5%. Weighted by ownership stakes, the shares are 36.6% and 56.0%.
• Investor-owned utilities served 71.6% of utility customers in 2025, cooperatives 13.8% and municipal utilities 11.0%.
• The Los Angeles Department of Water and Power was the largest public power utility (1,516,453 customers) and Pedernales Electric Cooperative the largest co-op (474,954).
• Average residential prices at the 20 largest utilities ran from 13.43 cents per kWh (Duke Energy Carolinas) to 37.52 cents (Pacific Gas and Electric bundled service) in 2025, against a US average of 17.23 cents.
• Pending deals: NextEra Energy agreed on May 15, 2026 to acquire Dominion Energy, which would give it 9.65 million customers on 2025 counts, and AES agreed on March 1, 2026 to a sale to a consortium led by GIP and EQT.

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How we built this report

Source selection: every customer, sales and revenue figure comes from the final 2025 release of Form EIA-861 (released October 7, 2026), a census of US electric utilities. National totals come from EIA's Electric Power Annual 2025. Parent companies come from fiscal 2025 SEC filings opened on EDGAR: Exhibit 21 subsidiary lists, or 10-K text where a parent files without one. Association figures (APPA, NRECA) are Tier 2 context only.

Customer definition: a utility's customers are its Part A (bundled) plus Part C (delivery-only) accounts in Sales_Ult_Cust_2025.xlsx, summed across states, plus the Texas ERCOT wires companies, which EIA reports separately in Delivery_Companies_2025.xlsx. Energy-only (Part B) and Texas retail provider (Part D) accounts belong to suppliers, not utilities, and are not credited to any utility. EIA's statewide adjustment rows and behind-the-meter solar providers are excluded from utility rankings. Territories are excluded.

Parent mapping: each operating utility is assigned to the parent that lists it in its latest annual filing (all fiscal 2025, except Avangrid, which filed Form 15 on January 2, 2025 after Iberdrola acquired it on December 23, 2024 and has filed no 10-K since; its fiscal 2023 Exhibit 21 and the merger 8-K are used, and archived 2026 copies of its four utilities' websites still carry the Avangrid name). Parents without an SEC document opened in this session are not rolled up. Oncor is credited in full to Sempra and flagged, because Sempra's interest is an indirect 80.25%. Ownership types are kept separate: public power and co-ops are ranked within their own classes.

Ownership basis: the primary ranking uses full consolidation, crediting each operating utility in full to the parent that controls it, as the parents' own financial statements do. A second ranking weights each utility by the parent's equity interest at December 31, 2025, taken from the 10-K text: Oncor 80.25% (Sempra), Duke Energy Indiana 80.1% (Duke Energy), AES Indiana and AES Ohio about 70% (AES). We searched the fiscal 2025 10-K text of 28 mapped parents for other minority interests in retail utilities and found none. Transactions signed but not closed by November 5, 2026 (NextEra and Dominion, AES, TXNM, Emera and Canadian Utilities, Xcel's Michigan sale) are recorded in the ledger but do not change the 2025 ranking.

Conflicting numbers: the EIA national total (165,488,106) counts Texas retail accounts, while the utility counts use Texas wires meters; the two differ by less than one percent. Shares of US customers use the EIA total. Ownership-type shares use the sum of long-form and short-form (EIA-861S) utility customers, because EIA's adjustment rows are not split by ownership.

Derived metrics: parent totals are sums of operating-utility rows; shares divide by the EIA national totals; residential price is bundled residential revenue divided by bundled residential MWh. Every formula and input row is in derived_metrics.csv, and scripts/ re-runs the whole build from the raw files.

Limitations: customers are accounts, not people. Delivery-only revenue excludes the energy charge. Bundled residential prices exclude customers who buy energy from community choice aggregators or retail suppliers. Consolidated revenue from 10-K XBRL uses each filer's own tag and covers all businesses. Market capitalization is not used. Not investment advice. Last updated 2026-11-02.

Last update: 2026-11-05 (first edition 2026-11-02). SEC documents in this revision were fetched with a User-Agent naming the publication and its website, without an email address.

This report presents published data with its limitations. It is not legal, financial or investment advice.

Sources by tier

Tier 1: primary and official sources (77)

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