HSA Contribution Calculator 2027

2027 limits — verbatim, Rev. Proc. 2026-24 §3.01(1): For calendar year 2027, the annual limitation on deductions under section 223(b)(2)(A) for an individual with self-only coverage under a high deductible health plan is $4,500. For calendar year 2027, the annual limitation on deductions under § 223(b)(2)(B) for an individual with family coverage under a high deductible health plan is $9,000.

HDHP definition — verbatim, §3.01(3): For calendar year 2027, a “high deductible health plan” is defined under section 223(c)(2)(A) as a health plan with an annual deductible that is not less than $1,750 for self-only coverage or $3,500 for family coverage, and for which the annual out-of-pocket expenses (deductibles, co-payments, and other amounts, but not premiums) do not exceed $8,700 for self-only coverage or $17,400 for family coverage.

Ordinary monthly method: IRC §223(b)(2) and Form 8889 use 1/12 of the annual amount for each eligible month, based on eligibility on the first day of the month. Enter only months with HSA-eligible HDHP coverage, no disqualifying other coverage, no Medicare enrollment, and no dependent status. This estimate assumes the selected coverage type stays the same for all entered months. IRC §223(b)(3) says In the case of an individual who has attained age 55 before the close of the taxable year; a December 31, 2027 birthday qualifies. The fixed $1,000 annual catch-up is not indexed and also prorates by eligible months under the Form 8889 Additional Contribution Amount Worksheet. Amounts display to cents.

Contributions and spouses: IRC §223(b)(4)(B), §106(d) and Pub. 969 count employer and cafeteria-plan salary-reduction amounts against the same ceiling, generally W-2 box 12 code W. Room left is your maximum less employer/payroll amounts, before the planned personal deposit. Over-limit amount is employer/payroll plus planned personal contributions less your maximum, floored at zero. The family base is shared between spouses: this estimate assigns that whole base to your HSA and assumes no spouse base contributions. Each catch-up belongs in its owner's HSA. The spouse toggle assumes your spouse is independently HSA-eligible for the same months and not enrolled in Medicare; age 66 alone does not establish eligibility.

Medicare and last-month rule: §223(b)(7) and Pub. 969 make the limit zero starting with the first Medicare-enrolled month, including retroactive enrollment. The requested Medicare toggle is a conservative whole-year $0 shortcut, not a calculation of eligible months before enrollment; calculate those months separately using Form 8889. Household/spouse room is not estimated with this shortcut. Under §223(b)(8), eligibility on December 1, 2027 may allow a full-year amount. The testing period is December 1, 2027 through December 31, 2028. Failure, other than death or disability, causes income inclusion and a 10% additional tax on the amount attributable to this rule, not the 20% tax on certain nonmedical distributions. The engine uses ordinary monthly proration, not the last-month rule.

2026 comparison: Rev. Proc. 2025-19 §2.01 sets $4,400 self-only / $8,750 family, $1,700 / $3,400 minimum deductibles and $8,500 / $17,000 maximum out-of-pocket expenses. The comparison row is the full-year base only, before catch-up or employer contributions. It is not a tax-savings figure.

State scope: California and New Jersey do not allow the federal HSA contribution deduction and tax HSA earnings under their state rules. California FTB Publication 1001 explicitly confirms this. New Jersey's treatment of HSA contributions and earnings differs from federal rules; confirm with the NJ Division of Taxation. No state tax, investment earnings, or 6% excess-contribution excise amount is calculated. This is an estimate, not advice.

Sources — accessed October 26, 2026: IRS Rev. Proc. 2026-24 §3.01(1), (3); IRS Rev. Proc. 2025-19 §2.01; IRC §223(b)(2), (3), (4), (7), (8) and §223(c)(2); IRS Publication 969; IRS Form 8889 instructions; IRS W-2 instructions, code W; California FTB Publication 1001, HSA section; New Jersey NJ-1040 instructions; New Jersey deductions guidance.