v3.26.3
Retirement Benefits (Tables)
 9 Months Ended
Sep. 30, 2026
Defined Benefit Plan Disclosure [Line Items]  
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 PlansOPEB Plan
Three Months EndedNine Months EndedThree Months EndedNine Months Ended
September 3020262025202620252026202520262025
CMS Energy, including Consumers
Net periodic credit
Service cost$6 $6 $18 $19 $2 $2 $6 $6 
Interest cost25 27 75 81 10 10 29 32 
Expected return on plan assets(60)(57)(179)(171)(31)(27)(93)(83)
Amortization of:
Net loss4 3 11 8 — — — 2 
Prior service cost (credit)— 1 2 3 (8)(8)(24)(25)
Settlement loss3 3 8 8 — — — — 
Net periodic credit$(22)$(17)$(65)$(52)$(27)$(23)$(82)$(68)
Consumers
Net periodic credit
Service cost$6 $6 $18 $18 $2 $2 $6 $6 
Interest cost24 26 71 77 9 11 28 32 
Expected return on plan assets(57)(54)(169)(162)(29)(26)(87)(78)
Amortization of:
Net loss4 2 10 7 — — — 2 
Prior service cost (credit)— 1 2 3 (7)(8)(23)(25)
Settlement loss3 3 8 8 — — — — 
Net periodic credit$(20)$(16)$(60)$(49)$(25)$(21)$(76)$(63)
Consumers Energy Company  
Defined Benefit Plan Disclosure [Line Items]  
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 PlansOPEB Plan
Three Months EndedNine Months EndedThree Months EndedNine Months Ended
September 3020262025202620252026202520262025
CMS Energy, including Consumers
Net periodic credit
Service cost$6 $6 $18 $19 $2 $2 $6 $6 
Interest cost25 27 75 81 10 10 29 32 
Expected return on plan assets(60)(57)(179)(171)(31)(27)(93)(83)
Amortization of:
Net loss4 3 11 8 — — — 2 
Prior service cost (credit)— 1 2 3 (8)(8)(24)(25)
Settlement loss3 3 8 8 — — — — 
Net periodic credit$(22)$(17)$(65)$(52)$(27)$(23)$(82)$(68)
Consumers
Net periodic credit
Service cost$6 $6 $18 $18 $2 $2 $6 $6 
Interest cost24 26 71 77 9 11 28 32 
Expected return on plan assets(57)(54)(169)(162)(29)(26)(87)(78)
Amortization of:
Net loss4 2 10 7 — — — 2 
Prior service cost (credit)— 1 2 3 (7)(8)(23)(25)
Settlement loss3 3 8 8 — — — — 
Net periodic credit$(20)$(16)$(60)$(49)$(25)$(21)$(76)$(63)