Tools · Open enrollment

HSA vs FSA calculator

HDHP + HSA vs copay plan + general health FSA. Caps from Rev. Proc. 2026-24 (2027) and 2025-19 / 2025-32 (2026). Read the open-enrollment guide first. Quotes from your SBC, not a benefits-fair poster.

Plan year Coverage Age 55 or older this year Enrolled in Medicare Expected billed charges this year Light-year billed Bad-year billed Federal + state + FICA combined %

Default 22% federal + 7.65% FICA. Add your state. Premiums are modeled pretax (section 125).

HDHP + HSA

Employee premium (annual) Deductible Coinsurance % after deductible In-network OOP max (not premiums) Employer HSA seed Your HSA contribution Limited-purpose FSA (dental/vision)

Copay / PPO + health FSA

Employee premium (annual) Deductible Coinsurance % after deductible In-network OOP max Health FSA election FSA leftover

HSA cap

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Net cost = employee premium + patient share − employer HSA − tax saved on employee HSA (and on FSA dollars that actually pay claims). Unused FSA is a cost unless you toggle carryover. HSA leftover is an asset, not a cost. 2027 HSA / HDHP: Rev. Proc. 2026-24. 2026 health FSA $3,400 / $680 carryover: Rev. Proc. 2025-32. Paid sequence: HSA playbook. Triple-tax mechanics: primer.