Effects of Regulation (Tables)

12 Months Ended

Dec. 31, 2023

Regulated Generating Units to be Retired

Plant	Net Book Value		Accelerated Depreciation Regulatory Asset		Cost of Removal Regulatory Liability			Projected Retirement Date		Current Authorized Recovery Period	Annual Depreciation (a)
	(dollars in millions)
Northeastern Plant, Unit 3	$	104.5	$	164.2	$	20.5	(b)	2026		(c)	$	15.0
Welsh Plant, Units 1 and 3	352.0		125.6		58.2		(d)	2028	(e)	(f)	38.6

(a)Represents the amount of annual depreciation that has been collected from customers over the prior 12-month period.

(b)Includes Northeastern Plant, Unit 4, which was retired in 2016. Removal of Northeastern Plant, Unit 4, will be performed with the removal of Northeastern Plant, Unit 3, after retirement.

(c)Northeastern Plant, Unit 3 is currently being recovered through 2040.

(d)Includes Welsh Plant, Unit 2, which was retired in 2016. Removal of Welsh Plant, Unit 2, will be performed with the removal of Welsh Plant, Units 1 and 3, after retirement.

(e)Represents projected retirement date of coal assets, units are being evaluated for conversion to natural gas after 2028.

(f)Unit 1 is being recovered through 2027 in the Louisiana jurisdiction and through 2037 in the Arkansas and Texas jurisdictions. Unit 3 is being recovered through 2032 in the Louisiana jurisdiction and through 2042 in the Arkansas and Texas jurisdictions.

Regulatory Assets

	AEP
	December 31,				Remaining Recovery Period
	2023		2022
Current Regulatory Assets	(in millions)
Under-recovered Fuel Costs - earns a return	$	357.4	$	625.7	1 year
Under-recovered Fuel Costs - does not earn a return	62.7		588.5		1 year
Unrecovered Winter Storm Fuel Costs - earns a return (a)	93.9		95.8		1 year
Total Current Regulatory Assets	$	514.0	$	1,310.0
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Welsh Plant, Units 1 and 3 Accelerated Depreciation	$	125.6	$	85.6
Pirkey Plant Accelerated Depreciation	114.4		116.5
Unrecovered Winter Storm Fuel Costs (a)	60.1		84.6
Other Regulatory Assets Pending Final Regulatory Approval	49.8		68.9
Total Regulatory Assets Currently Earning a Return	349.9		355.6
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	408.9		407.1
2020-2022 Virginia Triennial Under-Earnings	—		37.9
Other Regulatory Assets Pending Final Regulatory Approval	78.5		81.5
Total Regulatory Assets Currently Not Earning a Return	487.4		526.5
Total Regulatory Assets Pending Final Regulatory Approval	837.3		882.1
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant (b)	664.2		689.9		23 years
Long-term Under-recovered Fuel Costs - West Virginia	291.5		—		11 years
Storm-Related Costs	170.9		8.4		5 years
Plant Retirement Costs - Asset Retirement Obligation Costs	110.8		110.6		19 years
Long-term Under-recovered Fuel Costs - Virginia	107.0		223.3		2 years
Unrecovered Winter Storm Fuel Costs (a)	99.3		148.6		4 years
Fuel Mine Closure Costs - Texas	74.3		—		12 years
Pirkey Plant Accelerated Depreciation - Louisiana	65.8		63.0		9 years
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction	46.9		56.6		5 years
Kentucky Deferred Purchased Power Expenses	43.5		53.0		4 years
Ohio Basic Transmission Cost Rider	42.2		14.3		2 years
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station, Louisiana	40.8		45.1		9 years
Texas Mobile Temporary Emergency Electric Energy Facilities Rider	33.4		—		2 years
Environmental Control Projects	31.4		33.9		17 years
Meter Replacement Costs	23.5		34.2		4 years
Long-term Under-recovered Fuel Costs - Oklahoma	—		252.7
Other Regulatory Assets Approved for Recovery	101.4		125.0		various
Total Regulatory Assets Currently Earning a Return	1,946.9		1,858.6
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	1,054.1		975.4		12 years
Plant Retirement Costs - Asset Retirement Obligation Costs	330.2		308.5		19 years
Unrealized Loss on Forward Commitments	131.4		40.1		9 years
Unamortized Loss on Reacquired Debt	97.2		104.1		25 years
Fuel and Purchased Power Adjustment Rider	68.3		76.3		2 years
Cook Plant Nuclear Refueling Outage Levelization	55.7		81.2		2 years
OVEC Purchased Power	50.1		—		2 years
Plant Retirement Costs - Unrecovered Plant, Texas	48.7		51.7		23 years
Storm-Related Costs	38.5		11.9		2 years
2020-2022 Virginia Triennial Under Earnings	37.4		—		4 years
Ohio Enhanced Service Reliability Plan	35.3		33.3		2 years
Ohio Distribution Investment Rider	35.3		2.3		2 years
Postemployment Benefits	30.6		32.1		3 years
Peak Demand Reduction/Energy Efficiency	23.9		41.7		3 years
Other Regulatory Assets Approved for Recovery	271.5		262.7		various
Total Regulatory Assets Currently Not Earning a Return	2,308.2		2,021.3
Total Regulatory Assets Approved for Recovery	4,255.1		3,879.9
Total Noncurrent Regulatory Assets	$	5,092.4	$	4,762.0

(a)See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.

(b)Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.

	AEP Texas
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Texas Mobile Generation Lease Payments	$	—	$	17.6
Total Regulatory Assets Currently Earning a Return	—		17.6
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	37.7		26.7
Line Inspection Costs	5.7		4.5
Vegetation Management Program	5.2		5.2
Texas Retail Electric Provider Bad Debt Expense	4.0		4.1
Other Regulatory Assets Pending Final Regulatory Approval	11.7		8.9
Total Regulatory Assets Currently Not Earning a Return	64.3		49.4
Total Regulatory Assets Pending Final Regulatory Approval	64.3		67.0
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Texas Mobile Temporary Emergency Electric Energy Facilities Rider	33.4		—		2 years
Meter Replacement Costs	9.4		16.1		2 years
Other Regulatory Assets Approved for Recovery	0.7		1.4		various
Total Regulatory Assets Currently Earning a Return	43.5		17.5
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	183.2		173.2		12 years
Peak Demand Reduction/Energy Efficiency	9.2		11.9		2 years
Vegetation Management Program	6.8		12.1		2 years
Storm-Related Costs	4.3		8.5		2 years
Other Regulatory Assets Approved for Recovery	4.0		8.1		various
Total Regulatory Assets Currently Not Earning a Return	207.5		213.8
Total Regulatory Assets Approved for Recovery	251.0		231.3
Total Noncurrent Regulatory Assets	$	315.3	$	298.3

	AEPTCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Noncurrent Regulatory Assets
Regulatory assets approved for recovery:
Regulatory Assets Currently Not Earning a Return
PJM/SPP Annual Formula Rate True-up	$	3.1	$	7.2	2 years
Total Regulatory Assets Approved for Recovery	3.1		7.2
Total Noncurrent Regulatory Assets	$	3.1	$	7.2

	APCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return	$	147.4	$	180.7	1 year
Under-recovered Fuel Costs - does not earn a return	8.0		292.4		1 year
Total Current Regulatory Assets	$	155.4	$	473.1
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Other Regulatory Assets Pending Final Regulatory Approval	$	0.6	$	7.0
Total Regulatory Assets Currently Earning a Return	0.6		7.0
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - West Virginia	91.5		72.6
Plant Retirement Costs - Asset Retirement Obligation Costs	25.9		25.9
2020-2022 Virginia Triennial Under-Earnings	—		37.9
Other Regulatory Assets Pending Final Regulatory Approval	7.5		1.1
Total Regulatory Assets Currently Not Earning a Return	124.9		137.5
Total Regulatory Assets Pending Final Regulatory Approval	125.5		144.5
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Long-term Under-recovered Fuel Costs - West Virginia	154.2		—		11 years
Long-term Under-recovered Fuel Costs - Virginia	107.0		223.3		2 years
Plant Retirement Costs - Unrecovered Plant	72.0		75.6		20 years
Other Regulatory Assets Approved for Recovery	7.1		0.4		various
Total Regulatory Assets Currently Earning a Return	340.3		299.3
Regulatory Assets Currently Not Earning a Return
Plant Retirement Costs - Asset Retirement Obligation Costs	324.7		303.1		15 years
Pension and OPEB Funded Status	115.8		108.3		12 years
Unamortized Loss on Reacquired Debt	70.7		74.4		22 years
2020-2022 Virginia Triennial Under-Earnings	37.4		—		4 years
Virginia Transmission Rate Adjustment Clause	25.5		18.7		2 years
Unrealized Loss on Forward Commitments	21.9		—		3 years
Peak Demand Reduction/Energy Efficiency	15.0		15.8		3 years
Postemployment Benefits	14.9		13.7		3 years
Vegetation Management Program - West Virginia	12.9		13.7		2 years
Excess SO2 Allowance Inventory - Virginia	11.8		—		9 years
Virginia Generation Rate Adjustment Clause	10.9		8.0		2 years
Virginia Clean Economy Act	8.0		16.7		2 years
2017-2019 Virginia Triennial Under-Earnings	2.3		30.1		1 year
Other Regulatory Assets Approved for Recovery	17.5		12.3		various
Total Regulatory Assets Currently Not Earning a Return	689.3		614.8
Total Regulatory Assets Approved for Recovery	1,029.6		914.1
Total Noncurrent Regulatory Assets	$	1,155.1	$	1,058.6

	I&M
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs, Michigan - earns a return	$	14.8	$	9.0	1 year
Under-recovered Fuel Costs, Indiana - does not earn a return	—		38.1
Total Current Regulatory Assets	$	14.8	$	47.1
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Other Regulatory Assets Pending Final Regulatory Approval	$	0.2	$	0.1
Total Regulatory Assets Currently Earning a Return	0.2		0.1
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - Indiana	29.7		21.6
Other Regulatory Assets Pending Final Regulatory Approval	3.3		2.0
Total Regulatory Assets Currently Not Earning a Return	33.0		23.6
Total Regulatory Assets Pending Final Regulatory Approval	33.2		23.7
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant	122.5		147.0		5 years
Rockport Plant Dry Sorbent Injection System and Selective Catalytic Reduction	46.9		56.6		5 years
Cook Plant Uprate Project	22.9		25.3		10 years
Deferred Cook Plant Life Cycle Management Project Costs - Michigan, FERC	11.1		12.1		11 years
Cook Plant Turbine - Indiana	8.4		9.0		15 years
Other Regulatory Assets Approved for Recovery	17.5		20.6		various
Total Regulatory Assets Currently Earning a Return	229.3		270.6
Regulatory Assets Currently Not Earning a Return
Cook Plant Nuclear Refueling Outage Levelization	55.7		81.2		2 years
Pension and OPEB Funded Status	25.4		26.9		12 years
Excess SO2 Allowance Inventory - Indiana	14.8		—		5 years
Unamortized Loss on Reacquired Debt	11.8		12.9		25 years
Environmental Cost Rider - Indiana	8.1		6.6		2 years
Postemployment Benefits	7.0		7.7		3 years
Demand Side Management - Indiana	—		10.3
Other Regulatory Assets Approved for Recovery	21.0		19.7		various
Total Regulatory Assets Currently Not Earning a Return	143.8		165.3
Total Regulatory Assets Approved for Recovery	373.1		435.9
Total Noncurrent Regulatory Assets	$	406.3	$	459.6

	OPCo
	December 31,				Remaining Recovery Period
Regulatory Assets:	2023		2022
	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - does not earn a return	$	—	$	3.8	1 year
Total Current Regulatory Assets	$	—	$	3.8
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	$	23.6	$	33.8
Total Regulatory Assets Pending Final Regulatory Approval	23.6		33.8
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Ohio Basic Transmission Cost Rider	42.2		14.3		2 years
Ohio Distribution Decoupling	1.8		19.5		2 years
Ohio Economic Development Rider	—		1.1
Total Regulatory Assets Currently Earning a Return	44.0		34.9
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	147.1		142.7		12 years
Unrealized Loss on Forward Commitments	50.8		40.0		9 years
OVEC Purchased Power	50.1		—		2 years
Ohio Enhanced Service Reliability Plan	35.3		33.3		2 years
Ohio Distribution Investment Rider	35.3		2.3		2 years
Storm-Related Costs	30.9		—		1 year
Smart Grid Costs	26.3		25.4		2 years
Other Regulatory Assets Approved for Recovery	11.6		14.9		various
Total Regulatory Assets Currently Not Earning a Return	387.4		258.6
Total Regulatory Assets Approved for Recovery	431.4		293.5
Total Noncurrent Regulatory Assets	$	455.0	$	327.3

	PSO
	December 31,				Remaining Recovery Period
	2023		2022
Regulatory Assets:	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return	$	118.3	$	178.7	1 year
Total Current Regulatory Assets	$	118.3	$	178.7
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs	$	88.5	$	25.5
Other Regulatory Assets Pending Final Regulatory Approval	0.2		0.1
Total Regulatory Assets Pending Final Regulatory Approval	88.7		25.6
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Plant Retirement Costs - Unrecovered Plant (a)	254.1		240.6		23 years
Storm-Related Costs	26.2		8.4		5 years
Environmental Control Projects	22.5		23.9		17 years
Meter Replacement Costs	14.1		18.1		4 years
Long-term Under-recovered Fuel Costs - Oklahoma	—		252.7
Other Regulatory Assets Approved for Recovery	8.4		9.1		various
Total Regulatory Assets Currently Earning a Return	325.3		552.8
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	62.6		55.2		12 years
Unrealized Loss on Forward Commitments	29.9		—		2 years
Other Regulatory Assets Approved for Recovery	16.2		20.1		various
Total Regulatory Assets Currently Not Earning a Return	108.7		75.3
Total Regulatory Assets Approved for Recovery	434.0		628.1
Total Noncurrent Regulatory Assets	$	522.7	$	653.7

(a)Northeastern Plant, Unit 3 is approved for recovery through 2040, but expected to retire in 2026. PSO records a regulatory asset for accelerated depreciation. See “Regulated Generating Units to be Retired” section above for additional information.

	SWEPCo
	December 31,				Remaining Recovery Period
	2023		2022
Regulatory Assets:	(in millions)
Current Regulatory Assets
Under-recovered Fuel Costs - earns a return (a)	$	76.9	$	257.2	1 year
Unrecovered Winter Storm Fuel Costs - earns a return (b)	93.9		95.8		1 year
Total Current Regulatory Assets	$	170.8	$	353.0
Noncurrent Regulatory Assets
Regulatory assets pending final regulatory approval:
Regulatory Assets Currently Earning a Return
Welsh Plant, Units 1 and 3 Accelerated Depreciation	$	125.6	$	85.6
Pirkey Plant Accelerated Depreciation	114.4		116.5
Unrecovered Winter Storm Fuel Costs (b)	60.1		84.6
Dolet Hills Power Station Accelerated Depreciation (c)	12.0		9.7
Other Regulatory Assets Pending Final Regulatory Approval	26.0		34.5
Total Regulatory Assets Currently Earning a Return	338.1		330.9
Regulatory Assets Currently Not Earning a Return
Storm-Related Costs - Louisiana, Texas	56.0		151.5
Asset Retirement Obligation - Louisiana	—		11.8
Other Regulatory Assets Pending Final Regulatory Approval	13.7		16.0
Total Regulatory Assets Currently Not Earning a Return	69.7		179.3
Total Regulatory Assets Pending Final Regulatory Approval	407.8		510.2
Regulatory assets approved for recovery:
Regulatory Assets Currently Earning a Return
Storm-Related Costs - Louisiana	144.7		—		2 years
Unrecovered Winter Storm Fuel Costs (b)	99.3		148.6		4 years
Fuel Mine Closure Costs - Texas	74.3		—		12 years
Pirkey Plant Accelerated Depreciation - Louisiana	65.8		63.0		9 years
Plant Retirement Costs - Unrecovered Plant, Arkansas	44.4		13.1		19 years
Plant Retirement Costs - Unrecovered Plant, Dolet Hills Power Station - Louisiana	40.8		45.1		9 years
Environmental Controls Projects	8.9		10.0		9 years
Plant Retirement Costs - Unrecovered Plant, Welsh Plant, Unit 2 - Louisiana	—		35.2
Other Regulatory Assets Approved for Recovery	4.9		6.8		various
Total Regulatory Assets Currently Earning a Return	483.1		321.8
Regulatory Assets Currently Not Earning a Return
Pension and OPEB Funded Status	109.2		96.2		12 years
Plant Retirement Costs - Unrecovered Plant, Texas	48.7		51.7		23 years
North Central Wind Rider	20.2		6.4		2 years
Plant Retirement Costs - Unrecovered Plant, Arkansas	17.3		21.1		4 years
Unrealized Loss on Forward Commitments	15.4		—		2 years
Other Regulatory Assets Approved for Recovery	30.1		35.0		various
Total Regulatory Assets Currently Not Earning a Return	240.9		210.4
Total Regulatory Assets Approved for Recovery	724.0		532.2
Total Noncurrent Regulatory Assets	$	1,131.8	$	1,042.4

(a)Amounts include Arkansas and Texas jurisdictions.

(b)See “February 2021 Severe Winter Weather Impacts in SPP” section of SWEPCo Rate Matters in Note 4 for additional information.

(c)Amounts include the FERC jurisdiction.

Regulatory Liabilities

	AEP
	December 31,				Remaining
	2023		2022		Refund Period
Current Regulatory Liabilities	(in millions)
Over-recovered Fuel Costs - pays a return	$	3.3	$	1.4	1 year
Over-recovered Fuel Costs - does not pay a return	23.2		—		1 year
Total Current Regulatory Liabilities	$	26.5	$	1.4
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	103.1	$	149.7
Total Regulatory Liabilities Currently Paying a Return	103.1		149.7
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	103.1		—
Other Regulatory Liabilities Pending Final Regulatory Determination	1.7		4.1
Total Regulatory Liabilities Currently Not Paying a Return	104.8		4.1
Total Regulatory Liabilities Pending Final Regulatory Determination	207.9		153.8
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	3,563.5		3,392.4		(b)
Income Taxes, Net (a)	2,179.7		2,504.5		(c)
Rockport Plant, Unit 2 Accelerated Depreciation for Leasehold Improvements	44.9		53.8		5 years
Other Regulatory Liabilities Approved for Payment	35.0		32.7		various
Total Regulatory Liabilities Currently Paying a Return	5,823.1		5,983.4
Regulatory Liabilities Currently Not Paying a Return
Excess Nuclear Decommissioning Funding	1,721.9		1,318.5		(d)
Deferred Investment Tax Credits	154.5		237.3		31 years
Spent Nuclear Fuel	47.6		45.8		(d)
2017-2019 Virginia Triennial Revenue Provision	37.1		39.1		26 years
Demand Side Management	31.3		15.7		2 years
Over-recovered Fuel Costs - Ohio	26.1		32.2		9 years
PJM Transmission Enhancement Refund	22.8		34.1		2 years
PJM Costs and Off-system Sales Margin Sharing - Indiana	14.1		34.2		2 years
OVEC Purchased Power	—		47.1
Unrealized Gain on Forward Commitments	—		45.2
Other Regulatory Liabilities Approved for Payment	96.0		129.2		various
Total Regulatory Liabilities Currently Not Paying a Return	2,151.4		1,978.4
Total Regulatory Liabilities Approved for Payment	7,974.5		7,961.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	8,182.4	$	8,115.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $228 million and $277 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

(d)Relieved when plant is decommissioned.

	AEP Texas
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	13.0	$	13.0
Total Regulatory Liabilities Currently Paying a Return	13.0		13.0
Regulatory Liabilities Currently Not Paying a Return
Other Regulatory Liabilities Pending Final Regulatory Determination	1.5		1.8
Total Regulatory Liabilities Currently Not Paying a Return	1.5		1.8
Total Regulatory Liabilities Pending Final Regulatory Determination	14.5		14.8
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	797.1		766.8		(b)
Income Taxes, Net (a)	412.0		431.6		(c)
Other Regulatory Liabilities Approved for Payment	3.8		4.3		various
Total Regulatory Liabilities Currently Paying a Return	1,212.9		1,202.7
Regulatory Liabilities Currently Not Paying a Return
Transition and Restoration Charges	26.6		29.4		6 years
Other Regulatory Liabilities Approved for Payment	7.4		12.7		various
Total Regulatory Liabilities Currently Not Paying a Return	34.0		42.1
Total Regulatory Liabilities Approved for Payment	1,246.9		1,244.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,261.4	$	1,259.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets.

	AEPTCo
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	8.7	$	8.7
Total Regulatory Liabilities Pending Final Regulatory Determination	8.7		8.7
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	466.3		358.8		(b)
Income Taxes, Net (a)	308.7		355.8		(c)
Total Regulatory Liabilities Approved for Payment	775.0		714.6
Total Noncurrent Regulatory Liabilities	$	783.7	$	723.3

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $13 million and $16 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	APCo
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	7.9	$	30.5
Total Regulatory Liabilities Currently Paying a Return	7.9		30.5
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	19.7		—
Total Regulatory Liabilities Currently Not Paying a Return	19.7		—
Total Regulatory Liabilities Pending Final Regulatory Determination	27.6		30.5
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	759.6		713.5		(b)
Income Taxes, Net (a)	240.1		291.3		(c)
Deferred Investment Tax Credits	0.3		0.3		30 years
Total Regulatory Liabilities Currently Paying a Return	1,000.0		1,005.1
Regulatory Liabilities Currently Not Paying a Return
2017-2019 Virginia Triennial Revenue Provision	37.1		39.1		26 years
Over-recovered Deferred Wind Power Costs - Virginia	2.6		13.6		2 years
Unrealized Gain on Forward Commitments	—		34.5
Other Regulatory Liabilities Approved for Payment	14.6		20.8		various
Total Regulatory Liabilities Currently Not Paying a Return	54.3		108.0
Total Regulatory Liabilities Approved for Payment	1,054.3		1,113.1
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,081.9	$	1,143.6

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Relieved as removal costs are incurred.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $35 million and $19 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	I&M
	December 31,				Remaining Refund Period
Regulatory Liabilities:	2023		2022
	(in millions)
Current Regulatory Liabilities
Over-recovered Fuel Costs, Indiana - does not pay a return	$	23.2	$	—	1 year
Total Current Regulatory Liabilities	$	23.2	$	—
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a) (b)	$	(103.0)	$	(87.7)
Total Regulatory Liabilities Currently Paying a Return	(103.0)		(87.7)
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	22.8		—
Total Regulatory Liabilities Currently Not Paying a Return	22.8		—
Total Regulatory Liabilities Pending Final Regulatory Determination	(80.2)		(87.7)
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	168.1		170.7		(c)
Income Taxes, Net (a)	116.8		168.6		(d)
Renewable Energy Surcharge - Michigan	26.6		23.2		2 years
Other Regulatory Liabilities Approved for Payment	0.1		3.0		various
Total Regulatory Liabilities Currently Paying a Return	311.6		365.5
Regulatory Liabilities Currently Not Paying a Return
Excess Nuclear Decommissioning Funding	1,721.9		1,318.5		(e)
Spent Nuclear Fuel	47.6		45.8		(e)
Demand Side Management - Indiana	16.7		—		2 years
Deferred Investment Tax Credits	15.8		17.4		27 years
PJM Costs and Off-system Sales Margin Sharing - Indiana	14.1		34.2		2 years
Other Regulatory Liabilities Approved for Payment	4.8		8.5		various
Total Regulatory Liabilities Currently Not Paying a Return	1,820.9		1,424.4
Total Regulatory Liabilities Approved for Payment	2,132.5		1,789.9
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	2,052.3	$	1,702.2

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Represents an income tax related regulatory asset, which is presented within net regulatory liabilities on the balance sheet.

(c)Relieved as removal costs are incurred.

(d)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $25 million and $42 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

(e)Relieved when plant is decommissioned.

	OPCo
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	$	57.0	$	—
Other Regulatory Liabilities Pending Final Regulatory Determination	0.2		0.2
Total Regulatory Liabilities Pending Final Regulatory Determination	57.2		0.2
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	475.5		466.5		(a)
Income Taxes, Net (b)	408.2		451.9		(c)
Total Regulatory Liabilities Currently Paying a Return	883.7		918.4
Regulatory Liabilities Currently Not Paying a Return
Over-recovered Fuel Costs	26.1		32.2		9 years
Peak Demand Reduction/Energy Efficiency	23.2		23.6		2 years
PJM Transmission Enhancement Refund	9.8		14.7		2 years
OVEC Purchased Power	—		47.1
Other Regulatory Liabilities Approved for Payment	3.6		7.8		various
Total Regulatory Liabilities Currently Not Paying a Return	62.7		125.4
Total Regulatory Liabilities Approved for Payment	946.4		1,043.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	1,003.6	$	1,044.0

(a)Relieved as removal costs are incurred.

(b)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(c)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $132 million and $162 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 5 years.

	PSO
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	$	—	$	51.3
Total Regulatory Liabilities Currently Paying a Return	—		51.3
Regulatory Liabilities Currently Not Paying a Return
FERC 2021 Transmission Formula Rate Challenge Refunds	1.2		—
Total Regulatory Liabilities Currently Not Paying a Return	1.2		—
Total Regulatory Liabilities Pending Final Regulatory Determination	1.2		51.3
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (a)	395.7		380.1		(b)
Asset Removal Costs	317.5		316.3		(c)
Total Regulatory Liabilities Currently Paying a Return	713.2		696.4
Regulatory Liabilities Currently Not Paying a Return
Deferred Investment Tax Credits	47.2		48.2		18 years
Other Regulatory Liabilities Approved for Payment	4.0		13.2		various
Total Regulatory Liabilities Currently Not Paying a Return	51.2		61.4
Total Regulatory Liabilities Approved for Payment	764.4		757.8
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	765.6	$	809.1

(a)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(b)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets. Excess ADIT that is Not Subject to Rate Normalization Requirements were $51 million and $21 million for the years ended December 31, 2023 and 2022, respectively. The remaining balance of Excess ADIT that is Not Subject to Rate Normalization Requirements as of December 31, 2023 is to be refunded over 1 year.

(c)Relieved as removal costs are incurred.

	SWEPCo
	December 31,				Remaining Refund Period
	2023		2022
Regulatory Liabilities:	(in millions)
Current Regulatory Liabilities
Over-recovered Fuel Costs - pays a return (a)	$	3.3	$	1.4	1 year
Total Current Regulatory Liabilities	$	3.3	$	1.4
Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits
Regulatory liabilities pending final regulatory determination:
Regulatory Liabilities Currently Paying a Return
Income Taxes, Net (b)	$	7.0	$	7.0
Total Regulatory Liabilities Pending Final Regulatory Determination	7.0		7.0
Regulatory liabilities approved for payment:
Regulatory Liabilities Currently Paying a Return
Asset Removal Costs	443.2		481.2		(c)
Income Taxes, Net (b)	292.4		327.6		(d)
Other Regulatory Liabilities Approved for Payment	4.4		2.2		various
Total Regulatory Liabilities Currently Paying a Return	740.0		811.0
Regulatory Liabilities Currently Not Paying a Return
Other Regulatory Liabilities Approved for Payment	9.1		7.7		various
Total Regulatory Liabilities Currently Not Paying a Return	9.1		7.7
Total Regulatory Liabilities Approved for Payment	749.1		818.7
Total Noncurrent Regulatory Liabilities and Deferred Investment Tax Credits	$	756.1	$	825.7

(a)Amounts include Louisiana jurisdiction.

(b)Predominately pays a return due to the inclusion of Excess ADIT in rate base.

(c)Relieved as removal costs are incurred.

(d)Refunded over the period for which the related deferred income tax reverse, which is generally based on the expected life for the underlying assets. Excess ADIT Associated with Certain Depreciable Property is refunded over the remaining depreciable life of the underlying assets.