v3.25.4

Retirement Benefits (Tables)

12 Months Ended

Dec. 31, 2025

Defined Benefit Plan Disclosure [Line Items]

Schedule of SERP Trust Assets, ABO and Contributions

Presented in the following table are the fair values of trust assets and ABO for CMS Energy’s and Consumers’ DB SERP:

In Millions
Years Ended December 31			2025						2024
CMS Energy, including Consumers
Trust assets						$	122					$	127
ABO						104						105
Consumers
Trust assets						$	92					$	95
ABO						76						76

Schedule of Assumptions Used

Presented in the following table are the weighted-average assumptions used in CMS Energy’s, including Consumers’, retirement benefit plans to determine benefit obligations and net periodic benefit cost:

December 31			2025			2024			2023
Weighted average for benefit obligations1
Discount rate2
DB Pension Plan A			5.58		%	5.73		%	5.05		%
DB Pension Plan B			5.28			5.59			4.95
DB SERP			5.22			5.56			4.94
OPEB Plan			5.50			5.69			5.02
Rate of compensation increase
DB Pension Plan A			3.70			3.70			3.60
Weighted average for net periodic benefit cost1
Service cost discount rate2,3
DB Pension Plan A			5.77		%	5.08		%	5.27		%
DB SERP4			—			—			5.18
OPEB Plan			5.85			5.12			5.31
Interest cost discount rate2,3
DB Pension Plan A			5.43			4.93			5.12
DB Pension Plan B			5.30			4.87			5.06
DB SERP			5.29			4.87			5.06
OPEB Plan			5.39			4.91			5.10
Expected long-term rate of return on plan assets5
DB Pension Plans			7.30			7.50			7.20
OPEB Plan			7.15			7.50			7.20
Rate of compensation increase
DB Pension Plan A			3.70			3.60			3.60
DB SERP4			—			—			5.50

1The mortality assumption for benefit obligations and net periodic benefit cost was based on the Pri-2012 Mortality Table, with improvement scale MP-2021.

2The discount rate reflects the rate at which benefits could be effectively settled and is equal to the equivalent single rate resulting from a yield-curve analysis. This analysis incorporated the projected benefit payments specific to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan and the yields on high-quality corporate bonds rated Aa or better.

3CMS Energy and Consumers have elected to use a full-yield-curve approach in the estimation of service cost and interest cost; this approach applies individual spot rates along the yield curve to future projected benefit payments based on the time of payment.

4The last active participant in the DB SERP retired in 2023. Thus, the determination of the associated net periodic benefit cost no longer assumes a service cost discount rate nor a rate of compensation increase.

5CMS Energy and Consumers determined the long-term rate of return using historical market returns, the present and expected future economic environment, the capital market principles of risk and return, and the expert opinions of individuals and firms with financial market knowledge. CMS Energy and Consumers considered the asset allocation of the portfolio in forecasting the future expected total return of the portfolio. The goal was to determine a long-term rate of return that could be incorporated into the planning

of future cash flow requirements in conjunction with the change in the liability. Annually, CMS Energy and Consumers review for reasonableness and appropriateness the forecasted returns for various classes of assets used to construct an expected return model. CMS Energy’s and Consumers’ expected long-term rate of return on the assets of the DB Pension Plans was 7.30 percent in 2025. The actual return on the assets of the DB Pension Plans was 12.7 percent in 2025, 3.6 percent in 2024, and 12.6 percent in 2023.

Schedule of Net Benefit Costs

Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefit plans:

In Millions
																		DB Pension Plans and DB SERP																																				OPEB Plan
Years Ended December 31												2025						2024						2023																		2025						2024						2023
CMS Energy, including Consumers
Net periodic credit
Service cost																					$	25					$	28					$	29																							$	8					$	11					$	12
Interest cost																					114						109						112																								43						43						44
Expected return on plan assets																					(229)						(234)						(220)																								(111)						(115)						(103)
Amortization of:
Net loss																					11						12						12																								3						4						12
Prior service cost (credit)																					4						4						4																								(34)						(31)						(41)
Settlement loss																					11						11						11																								—						—						—
Net periodic credit																					$	(64)					$	(70)					$	(52)																							$	(91)					$	(88)					$	(76)
Consumers
Net periodic credit
Service cost																					$	24					$	27					$	28																							$	8					$	11					$	11
Interest cost																					106						102						105																								42						41						42
Expected return on plan assets																					(215)						(221)						(208)																								(104)						(107)						(95)
Amortization of:
Net loss																					10						11						11																								3						4						12
Prior service cost (credit)																					4						4						4																								(33)						(30)						(40)
Settlement loss																					11						11						11																								—						—						—
Net periodic credit																					$	(60)					$	(66)					$	(49)																							$	(84)					$	(81)					$	(70)

Schedule of Funded Status of Retirement Benefit Plans

Presented in the following table are reconciliations of the funded status of CMS Energy’s and Consumers’ retirement benefit plans with their retirement benefit plans’ liabilities:

In Millions
			DB Pension Plans															DB SERP															OPEB Plan
Years Ended December 31			2025						2024									2025						2024									2025						2024
CMS Energy, including Consumers
Benefit obligation at beginning of period						$	2,094					$	2,195								$	105					$	114								$	831					$	900
Service cost						25						28									—						—									8						11
Interest cost						109						104									5						5									43						43
Plan amendments						—						—									—						—									—						(25)
Actuarial loss (gain)						53			1			(91)			1						4						(4)									2			1			(40)			1
Benefits paid						(158)						(142)									(10)						(10)									(54)						(58)
Benefit obligation at end of period						$	2,123					$	2,094								$	104					$	105								$	830					$	831
Plan assets at fair value at beginning of period						$	2,964					$	3,004								$	—					$	—								$	1,588					$	1,559
Actual return on plan assets						371						102									—						—									197						86
Company contribution						—						—									10						10									—						—
Actual benefits paid						(158)						(142)									(10)						(10)									(52)						(57)
Plan assets at fair value at end of period						$	3,177					$	2,964								$	—					$	—								$	1,733					$	1,588
Funded status						$	1,054		2			$	870		2						$	(104)					$	(105)								$	903					$	757
Consumers
Benefit obligation at beginning of period																					$	76					$	83								$	801					$	867
Service cost																					—						—									8						11
Interest cost																					4						4									42						41
Plan amendments																					—						—									—						(24)
Actuarial loss (gain)																					3						(4)									1			1			(38)			1
Benefits paid																					(7)						(7)									(51)						(56)
Benefit obligation at end of period																					$	76					$	76								$	801					$	801
Plan assets at fair value at beginning of period																					$	—					$	—								$	1,479					$	1,453
Actual return on plan assets																					—						—									184						80
Company contribution																					7						7									—						—
Actual benefits paid																					(7)						(7)									(50)						(54)
Plan assets at fair value at end of period																					$	—					$	—								$	1,613					$	1,479
Funded status																					$	(76)					$	(76)								$	812					$	678

1The actuarial losses for 2025 for the DB Pension Plans and OPEB Plans were primarily the result of lower discount rates. The actuarial gains for 2024 for the DB Pension Plans and OPEB Plan were primarily the result of higher discount rates.

2The total funded status of the DB Pension Plans attributable to Consumers, based on an allocation of expenses, was $1.0 billion at December 31, 2025 and $836 million at December 31, 2024.

Schedule of Retirement Benefit Plan Assets (Liabilities)

Presented in the following table is the classification of CMS Energy’s and Consumers’ retirement benefit plans’ assets and liabilities:

In Millions
December 31			2025						2024
CMS Energy, including Consumers
Non-current assets
DB Pension Plans						$	1,054					$	870
OPEB Plan						903						757
Current liabilities
DB SERP						10						10
Non-current liabilities
DB SERP						94						95
Consumers
Non-current assets
DB Pension Plans						$	1,009					$	836
OPEB Plan						812						678
Current liabilities
DB SERP						7						7
Non-current liabilities
DB SERP						69						69

Schedule of Net Periodic Benefit Cost Not Yet Recognized

Presented in the following table are the amounts recognized in regulatory assets and AOCI that have not been recognized as components of net periodic benefit cost. For additional details on regulatory assets see Note 3, Regulatory Matters.

In Millions
			DB Pension Plans and DB SERP															OPEB Plan
December 31			2025						2024									2025						2024
CMS Energy, including Consumers
Regulatory assets
Net loss						$	548					$	653								$	93					$	176
Prior service cost (credit)						9						12									(61)						(94)
Regulatory assets						$	557					$	665								$	32					$	82
AOCI
Net loss (gain)						57						60									(7)						(3)
Prior service credit						—						—									(2)						(2)
Total amounts recognized in regulatory assets and AOCI						$	614					$	725								$	23					$	77
Consumers
Regulatory assets
Net loss						$	548					$	653								$	93					$	176
Prior service cost (credit)						9						12									(61)						(94)
Regulatory assets						$	557					$	665								$	32					$	82
AOCI
Net loss						18						15									—						—
Total amounts recognized in regulatory assets and AOCI						$	575					$	680								$	32					$	82

Schedule of Allocation of Plan Assets

Presented in the following tables are the fair values of the assets of CMS Energy’s, including Consumers’, DB Pension Plans and OPEB Plan, by asset category and by level within the fair value hierarchy. For additional details regarding the fair value hierarchy, see Note 6, Fair Value Measurements.

In Millions
			DB Pension Plans
			December 31, 2025																					December 31, 2024
			Total						Level 1						Level 2									Total						Level 1						Level 2
Cash and short-term investments						$	162					$	162					$	—								$	148					$	148					$	—
Mutual funds						—						—						—									—						—						—
						$	162					$	162					$	—								$	148					$	148					$	—
Pooled funds						3,015																					2,816
Total						$	3,177																				$	2,964

In Millions
			OPEB Plan
			December 31, 2025																					December 31, 2024
			Total						Level 1						Level 2									Total						Level 1						Level 2
Cash and short-term investments						$	72					$	72					$	—								$	35					$	35					$	—
U.S. government and agencies securities						15						—						15									13						—						13
Corporate debt						69						—						69									68						—						68
State and municipal bonds						4						—						4									2						—						2
Foreign bonds						16						—						16									15						—						15
Common stocks						215						215						—									170						170						—
Mutual funds						75						75						—									53						53						—
						$	466					$	362					$	104								$	356					$	258					$	98
Pooled funds						1,267																					1,232
Total						$	1,733																				$	1,588

Schedule of Asset Allocation

Presented in the following table are the investment components of the assets of CMS Energy’s DB Pension Plans and OPEB Plan as of December 31, 2025:

			DB Pension Plans						OPEB Plan
Fixed-income securities						39.2		%				37.6		%
Equity securities						38.7						42.4
Real asset investments						9.3						8.8
Return-seeking fixed income						7.1						5.6
Liquid alternative investments						4.3						3.7
Cash and cash equivalents						1.4						1.9
						100.0		%				100.0		%

Schedule of Expected Benefit Payments

Presented in the following table are the expected benefit payments for each of the next five years and the five‑year period thereafter:

In Millions
			DB Pension Plans						DB SERP						OPEB Plan
CMS Energy, including Consumers
2026						$	164					$	10					$	59
2027						165						10						61
2028						164						10						62
2029						164						9						62
2030						164						9						62
2031-2035						801						41						305
Consumers
2026						$	154					$	7					$	57
2027						155						7						58
2028						154						7						59
2029						155						6						59
2030						154						6						60
2031-2035						756						29						292

Consumers Energy Company

Defined Benefit Plan Disclosure [Line Items]

Schedule of SERP Trust Assets, ABO and Contributions

Presented in the following table are the fair values of trust assets and ABO for CMS Energy’s and Consumers’ DB SERP:

In Millions
Years Ended December 31			2025						2024
CMS Energy, including Consumers
Trust assets						$	122					$	127
ABO						104						105
Consumers
Trust assets						$	92					$	95
ABO						76						76

Schedule of Assumptions Used

Presented in the following table are the weighted-average assumptions used in CMS Energy’s, including Consumers’, retirement benefit plans to determine benefit obligations and net periodic benefit cost:

December 31			2025			2024			2023
Weighted average for benefit obligations1
Discount rate2
DB Pension Plan A			5.58		%	5.73		%	5.05		%
DB Pension Plan B			5.28			5.59			4.95
DB SERP			5.22			5.56			4.94
OPEB Plan			5.50			5.69			5.02
Rate of compensation increase
DB Pension Plan A			3.70			3.70			3.60
Weighted average for net periodic benefit cost1
Service cost discount rate2,3
DB Pension Plan A			5.77		%	5.08		%	5.27		%
DB SERP4			—			—			5.18
OPEB Plan			5.85			5.12			5.31
Interest cost discount rate2,3
DB Pension Plan A			5.43			4.93			5.12
DB Pension Plan B			5.30			4.87			5.06
DB SERP			5.29			4.87			5.06
OPEB Plan			5.39			4.91			5.10
Expected long-term rate of return on plan assets5
DB Pension Plans			7.30			7.50			7.20
OPEB Plan			7.15			7.50			7.20
Rate of compensation increase
DB Pension Plan A			3.70			3.60			3.60
DB SERP4			—			—			5.50

1The mortality assumption for benefit obligations and net periodic benefit cost was based on the Pri-2012 Mortality Table, with improvement scale MP-2021.

2The discount rate reflects the rate at which benefits could be effectively settled and is equal to the equivalent single rate resulting from a yield-curve analysis. This analysis incorporated the projected benefit payments specific to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan and the yields on high-quality corporate bonds rated Aa or better.

3CMS Energy and Consumers have elected to use a full-yield-curve approach in the estimation of service cost and interest cost; this approach applies individual spot rates along the yield curve to future projected benefit payments based on the time of payment.

4The last active participant in the DB SERP retired in 2023. Thus, the determination of the associated net periodic benefit cost no longer assumes a service cost discount rate nor a rate of compensation increase.

5CMS Energy and Consumers determined the long-term rate of return using historical market returns, the present and expected future economic environment, the capital market principles of risk and return, and the expert opinions of individuals and firms with financial market knowledge. CMS Energy and Consumers considered the asset allocation of the portfolio in forecasting the future expected total return of the portfolio. The goal was to determine a long-term rate of return that could be incorporated into the planning

of future cash flow requirements in conjunction with the change in the liability. Annually, CMS Energy and Consumers review for reasonableness and appropriateness the forecasted returns for various classes of assets used to construct an expected return model. CMS Energy’s and Consumers’ expected long-term rate of return on the assets of the DB Pension Plans was 7.30 percent in 2025. The actual return on the assets of the DB Pension Plans was 12.7 percent in 2025, 3.6 percent in 2024, and 12.6 percent in 2023.

Schedule of Net Benefit Costs

Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefit plans:

In Millions
																		DB Pension Plans and DB SERP																																				OPEB Plan
Years Ended December 31												2025						2024						2023																		2025						2024						2023
CMS Energy, including Consumers
Net periodic credit
Service cost																					$	25					$	28					$	29																							$	8					$	11					$	12
Interest cost																					114						109						112																								43						43						44
Expected return on plan assets																					(229)						(234)						(220)																								(111)						(115)						(103)
Amortization of:
Net loss																					11						12						12																								3						4						12
Prior service cost (credit)																					4						4						4																								(34)						(31)						(41)
Settlement loss																					11						11						11																								—						—						—
Net periodic credit																					$	(64)					$	(70)					$	(52)																							$	(91)					$	(88)					$	(76)
Consumers
Net periodic credit
Service cost																					$	24					$	27					$	28																							$	8					$	11					$	11
Interest cost																					106						102						105																								42						41						42
Expected return on plan assets																					(215)						(221)						(208)																								(104)						(107)						(95)
Amortization of:
Net loss																					10						11						11																								3						4						12
Prior service cost (credit)																					4						4						4																								(33)						(30)						(40)
Settlement loss																					11						11						11																								—						—						—
Net periodic credit																					$	(60)					$	(66)					$	(49)																							$	(84)					$	(81)					$	(70)

Schedule of Funded Status of Retirement Benefit Plans

Presented in the following table are reconciliations of the funded status of CMS Energy’s and Consumers’ retirement benefit plans with their retirement benefit plans’ liabilities:

In Millions
			DB Pension Plans															DB SERP															OPEB Plan
Years Ended December 31			2025						2024									2025						2024									2025						2024
CMS Energy, including Consumers
Benefit obligation at beginning of period						$	2,094					$	2,195								$	105					$	114								$	831					$	900
Service cost						25						28									—						—									8						11
Interest cost						109						104									5						5									43						43
Plan amendments						—						—									—						—									—						(25)
Actuarial loss (gain)						53			1			(91)			1						4						(4)									2			1			(40)			1
Benefits paid						(158)						(142)									(10)						(10)									(54)						(58)
Benefit obligation at end of period						$	2,123					$	2,094								$	104					$	105								$	830					$	831
Plan assets at fair value at beginning of period						$	2,964					$	3,004								$	—					$	—								$	1,588					$	1,559
Actual return on plan assets						371						102									—						—									197						86
Company contribution						—						—									10						10									—						—
Actual benefits paid						(158)						(142)									(10)						(10)									(52)						(57)
Plan assets at fair value at end of period						$	3,177					$	2,964								$	—					$	—								$	1,733					$	1,588
Funded status						$	1,054		2			$	870		2						$	(104)					$	(105)								$	903					$	757
Consumers
Benefit obligation at beginning of period																					$	76					$	83								$	801					$	867
Service cost																					—						—									8						11
Interest cost																					4						4									42						41
Plan amendments																					—						—									—						(24)
Actuarial loss (gain)																					3						(4)									1			1			(38)			1
Benefits paid																					(7)						(7)									(51)						(56)
Benefit obligation at end of period																					$	76					$	76								$	801					$	801
Plan assets at fair value at beginning of period																					$	—					$	—								$	1,479					$	1,453
Actual return on plan assets																					—						—									184						80
Company contribution																					7						7									—						—
Actual benefits paid																					(7)						(7)									(50)						(54)
Plan assets at fair value at end of period																					$	—					$	—								$	1,613					$	1,479
Funded status																					$	(76)					$	(76)								$	812					$	678

1The actuarial losses for 2025 for the DB Pension Plans and OPEB Plans were primarily the result of lower discount rates. The actuarial gains for 2024 for the DB Pension Plans and OPEB Plan were primarily the result of higher discount rates.

2The total funded status of the DB Pension Plans attributable to Consumers, based on an allocation of expenses, was $1.0 billion at December 31, 2025 and $836 million at December 31, 2024.

Schedule of Retirement Benefit Plan Assets (Liabilities)

Presented in the following table is the classification of CMS Energy’s and Consumers’ retirement benefit plans’ assets and liabilities:

In Millions
December 31			2025						2024
CMS Energy, including Consumers
Non-current assets
DB Pension Plans						$	1,054					$	870
OPEB Plan						903						757
Current liabilities
DB SERP						10						10
Non-current liabilities
DB SERP						94						95
Consumers
Non-current assets
DB Pension Plans						$	1,009					$	836
OPEB Plan						812						678
Current liabilities
DB SERP						7						7
Non-current liabilities
DB SERP						69						69

Schedule of Net Periodic Benefit Cost Not Yet Recognized

Presented in the following table are the amounts recognized in regulatory assets and AOCI that have not been recognized as components of net periodic benefit cost. For additional details on regulatory assets see Note 3, Regulatory Matters.

In Millions
			DB Pension Plans and DB SERP															OPEB Plan
December 31			2025						2024									2025						2024
CMS Energy, including Consumers
Regulatory assets
Net loss						$	548					$	653								$	93					$	176
Prior service cost (credit)						9						12									(61)						(94)
Regulatory assets						$	557					$	665								$	32					$	82
AOCI
Net loss (gain)						57						60									(7)						(3)
Prior service credit						—						—									(2)						(2)
Total amounts recognized in regulatory assets and AOCI						$	614					$	725								$	23					$	77
Consumers
Regulatory assets
Net loss						$	548					$	653								$	93					$	176
Prior service cost (credit)						9						12									(61)						(94)
Regulatory assets						$	557					$	665								$	32					$	82
AOCI
Net loss						18						15									—						—
Total amounts recognized in regulatory assets and AOCI						$	575					$	680								$	32					$	82

Schedule of Expected Benefit Payments

Presented in the following table are the expected benefit payments for each of the next five years and the five‑year period thereafter:

In Millions
			DB Pension Plans						DB SERP						OPEB Plan
CMS Energy, including Consumers
2026						$	164					$	10					$	59
2027						165						10						61
2028						164						10						62
2029						164						9						62
2030						164						9						62
2031-2035						801						41						305
Consumers
2026						$	154					$	7					$	57
2027						155						7						58
2028						154						7						59
2029						155						6						59
2030						154						6						60
2031-2035						756						29						292

X

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