Retirement Plans and Postretirement Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2026

Retirement Plans and Postretirement Benefit Plans [Abstract]

Schedule of Defined Benefit Plans Disclosures

The following tables present the net periodic benefit cost components, before consideration of capitalized amounts, of OGE Energy's Pension Plan, Restoration of Retirement Income Plan and postretirement benefit plans that are included in the condensed financial statements. Service cost is presented within Other Operation and Maintenance Expense, and the remaining net periodic benefit cost components as listed in the following tables are presented within Other Net Periodic Benefit Expense in the statements of income. OG&E recovers specific amounts of pension and postretirement medical costs in rates approved in its Oklahoma rate reviews. In accordance with approved orders, OG&E defers the difference between actual pension and postretirement medical expenses and the amount approved in its last Oklahoma rate review as a regulatory asset or regulatory liability. These amounts have

been recorded in the Pension tracker in the regulatory assets and liabilities table in Note 1 and within Other Net Periodic Benefit Expense in the statements of income.


		Pension Plan																Restoration of Retirement Income Plan
		Three Months Ended								Six Months Ended								Three Months Ended								Six Months Ended
OGE Energy		June 30,								June 30,								June 30,								June 30,
(In millions)		2026				2025				2026				2025				2026				2025				2026				2025
Service cost		$	1.2			$	1.3			$	2.6			$	2.7			$	0.3			$	0.2			$	0.6			$	0.5
Interest cost			4.0				4.1				7.9				8.1				0.2				0.1				0.3				0.2
Expected return on plan assets			(4.6	)			(4.2	)			(8.7	)			(8.3	)			—				—				—				—
Amortization of net loss			1.4				1.6				3.0				3.1				—				—				—				—
Amortization of unrecognized prior service cost (A)			—				—				—				—				—				0.2				0.1				0.2
Net periodic benefit cost		$	2.0			$	2.8			$	4.8			$	5.6			$	0.5			$	0.5			$	1.0			$	0.9

(A) Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.


		Pension Plan																Restoration of Retirement Income Plan
		Three Months Ended								Six Months Ended								Three Months Ended								Six Months Ended
OG&E		June 30,								June 30,								June 30,								June 30,
(In millions)		2026				2025				2026				2025				2026				2025				2026				2025
Service cost		$	1.2			$	1.3			$	2.6			$	2.7			$	—			$	—			$	—			$	—
Interest cost			3.4				3.6				6.8				7.1				0.1				0.1				0.1				0.1
Expected return on plan assets			(3.9	)			(3.6	)			(7.5	)			(7.1	)			—				—				—				—
Amortization of net loss			1.3				1.5				2.8				2.9				—				—				—				—
Total net periodic benefit cost			2.0				2.8				4.7				5.6				0.1				0.1				0.1				0.1
Plus: Amount allocated from OGE Energy			—				—				—				—				0.5				0.4				0.9				0.8
Net periodic benefit cost		$	2.0			$	2.8			$	4.7			$	5.6			$	0.6			$	0.5			$	1.0			$	0.9

In addition to the net periodic benefit cost amounts recognized, as presented in the tables above, for the Pension and Restoration of Retirement Income Plans during the three and six months ended June 30, 2026 and 2025, the Registrants recognized the following:


		Three Months Ended								Six Months Ended
		June 30,								June 30,
(In millions)		2026				2025				2026				2025
Change in pension expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A)		$	(0.8	)		$	(0.2	)		$	(1.1	)		$	(0.4	)

(A)

Included in the pension regulatory asset, as indicated in the regulatory assets and liabilities table in Note 1.


		OGE Energy																OG&E
		Postretirement Benefit Plans																Postretirement Benefit Plans
		Three Months Ended								Six Months Ended								Three Months Ended								Six Months Ended
		June 30,								June 30,								June 30,								June 30,
(In millions)		2026				2025				2026				2025				2026				2025				2026				2025
Service cost		$	—			$	—			$	—			$	—			$	—			$	—			$	—			$	—
Interest cost			1.0				1.4				2.2				2.7				0.8				1.1				1.7				2.1
Expected return on plan assets			(0.3	)			(0.4	)			(0.7	)			(0.8	)			(0.3	)			(0.3	)			(0.6	)			(0.7	)
Amortization of net (gain) loss			(0.1	)			0.2				(0.1	)			0.2				—				0.2				—				0.3
Total net periodic benefit cost			0.6				1.2				1.4				2.1				0.5				1.0				1.1				1.7
Plus: Amount allocated from OGE Energy																			0.1				0.1				0.2				0.2
Net periodic benefit cost		$	0.6			$	1.2			$	1.4			$	2.1			$	0.6			$	1.1			$	1.3			$	1.9

In addition to the net periodic benefit cost amounts recognized, as presented in the table above, for the postretirement benefit plans during the three and six months ended June 30, 2026 and 2025, the Registrants recognized the following:


		Three Months Ended								Six Months Ended
		June 30,								June 30,
(In millions)		2026				2025				2026				2025
Change in postretirement expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A)		$	(0.2	)		$	0.3			$	(0.2	)		$	0.3

(A)

Included in the pension regulatory asset, as indicated in the regulatory assets and liabilities table in Note 1.

Schedule of Capitalized Pension and Postretirement Cost

The following table presents the amount of net periodic benefit cost capitalized and attributable to each of the Registrants for OGE Energy's Pension Plan and postretirement benefit plans for the three and six months ended June 30, 2026 and 2025.


		Three Months Ended								Six Months Ended
OGE Energy and OG&E		June 30,								June 30,
(In millions)		2026				2025				2026				2025
Capitalized portion of net periodic pension benefit cost		$	0.6			$	0.6			$	1.2			$	1.2
Capitalized portion of net periodic postretirement benefit cost		$	—			$	—			$	—			$	—