ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2025

Accounting Policies [Abstract]

Schedule of Cash and Cash Equivalents

The following tables provide a reconciliation of Cash, Cash Equivalents and Restricted Cash reported within the balance sheets that sum to the total of the same amounts shown on the statement of cash flows:

	AEP				AEP Texas				APCo				SWEPCo
	Year Ended December 31,
	2025		2024		2025		2024		2025		2024		2025		2024
	(in millions)
Cash and Cash Equivalents	$	197	$	203	$	—	$	—	$	5	$	4	$	2	$	2
Restricted Cash	71		43		14		24		18		16		15		3
Total Cash, Cash Equivalents and Restricted Cash	$	268	$	246	$	14	$	24	$	23	$	20	$	17	$	5

Schedule of Restrictions on Cash and Cash Equivalents

The following tables provide a reconciliation of Cash, Cash Equivalents and Restricted Cash reported within the balance sheets that sum to the total of the same amounts shown on the statement of cash flows:

	AEP				AEP Texas				APCo				SWEPCo
	Year Ended December 31,
	2025		2024		2025		2024		2025		2024		2025		2024
	(in millions)
Cash and Cash Equivalents	$	197	$	203	$	—	$	—	$	5	$	4	$	2	$	2
Restricted Cash	71		43		14		24		18		16		15		3
Total Cash, Cash Equivalents and Restricted Cash	$	268	$	246	$	14	$	24	$	23	$	20	$	17	$	5

Schedule of Significant Customers

AEP Texas had significant customers which account for the following percentages of Total Revenues for the years ended December 31 and Accounts Receivable – Customers as of December 31:

Significant Customers of AEP Texas:
NRG Energy and Vistra Corp	2025		2024		2023
Percentage of Total Revenues	38	%	40	%	41	%
Percentage of Accounts Receivable – Customers	33	%	37	%	34	%

AEPTCo had significant transactions with AEP Subsidiaries which on a combined basis account for the following percentages of Total Revenues for the years ended December 31 and Total Accounts Receivable as of December 31:

Significant Customers of AEPTCo:
AEP Subsidiaries	2025		2024		2023
Percentage of Total Revenues	81	%	80	%	79	%
Percentage of Total Accounts Receivable	62	%	69	%	60	%

Schedule of Defined Benefit Plan, Plan Assets, Allocation

The current target asset allocations are as follows:

Pension Plan Assets	Target
Equity	35	%
Fixed Income	49	%
Other Investments	15	%
Cash and Cash Equivalents	1	%
OPEB Plans Assets	Target
Equity	63	%
Fixed Income	36	%
Cash and Cash Equivalents	1	%

Schedule of Earnings Per Share, Basic and Diluted

The following table presents AEP’s basic and diluted EPS calculations included on the statements of income:

	Years Ended December 31,
	2025				2024				2023
	(in millions, except per-share data)
			$/share				$/share				$/share
Earnings Attributable to AEP Common Shareholders	$	3,580			$	2,967			$	2,208
Weighted-Average Number of Basic AEP Common Shares Outstanding	534.5		$	6.70	530.1		$	5.60	518.9		$	4.26
Weighted-Average Dilutive Effect	3.0		(0.04)		1.2		(0.02)		1.3		(0.02)
Weighted-Average Number of Diluted AEP Common Shares Outstanding	537.5		$	6.66	531.3		$	5.58	520.2		$	4.24

Schedule of Supplementary Income Statement Information

The following tables provide the components of Depreciation and Amortization for the years ended December 31, 2025, 2024 and 2023:

2025
Depreciation and Amortization	AEP		AEP Texas		AEPTCo		APCo		I&M		OPCo		PSO		SWEPCo
	(in millions)
Depreciation and Amortization of Property, Plant and Equipment	$	3,325	$	420	$	478	$	652	$	471	$	380	$	293	$	391
Amortization of Certain Securitized Assets	46		18		—		—		—		—		—		20
Amortization of Regulatory Assets and Liabilities	9		3		—		(20)		43		—		(33)		18
Total Depreciation and Amortization	$	3,380	$	441	$	478	$	632	$	514	$	380	$	260	$	429

2024
Depreciation and Amortization	AEP		AEP Texas		AEPTCo		APCo		I&M		OPCo		PSO		SWEPCo
	(in millions)
Depreciation and Amortization of Property, Plant and Equipment	$	3,149	$	406	$	431	$	600	$	456	$	386	$	263	$	375
Amortization of Certain Securitized Assets	91		91		—		—		—		—		—		—
Amortization of Regulatory Assets and Liabilities	50		(3)		—		2		25		—		9		14
Total Depreciation and Amortization	$	3,290	$	494	$	431	$	602	$	481	$	386	$	272	$	389

2023
Depreciation and Amortization	AEP		AEP Texas		AEPTCo		APCo		I&M		OPCo		PSO		SWEPCo
	(in millions)
Depreciation and Amortization of Property, Plant and Equipment	$	2,927	$	380	$	394	$	571	$	440	$	316	$	241	$	323
Amortization of Certain Securitized Assets	92		92		—		—		—		—		—		—
Amortization of Regulatory Assets and Liabilities	71		(3)		—		1		30		—		15		20
Total Depreciation and Amortization	$	3,090	$	469	$	394	$	572	$	470	$	316	$	256	$	343

Schedule of Supplementary Cash Flow Information

	Years Ended December 31,
Cash Flow Information	2025		2024		2023
	(in millions)
Cash Paid for:
Interest, Net of Capitalized Amounts	$	1,894	$	1,838	$	1,674
Noncash Investing and Financing Activities:
Acquisitions Under Finance Leases	44		30		49
Construction Expenditures Included in Current Liabilities as of December 31,	1,935		1,312		842
Acquisition of Nuclear Fuel Included in Current Liabilities as of December 31,	10		24		24
Noncash Increase in Noncurrent Assets from the Sale of the Competitive Contracted Renewables Portfolio	—		—		75