HSA Contribution Limit Calculator
Your Health Savings Account (HSA) contribution limit is the IRS annual maximum for your coverage type, plus an age-55 catch-up if you qualify, prorated by the months you were covered by a high-deductible health plan (HDHP). Because the IRS indexes the dollar limits each year, this calculator takes the self-only limit, family limit and catch-up amount as editable inputs: enter the current figures from the IRS revenue procedure, your coverage type, eligible months and contributions already made, and it returns your limit and remaining room.
HSA limit formula
Annual limit = self-only or family limit by coverage type Prorated base = annual limit x (eligible months / 12) Total limit = prorated base + (catch-up if age 55+) Remaining room = total limit - already contributed
The catch-up is not prorated in this simplified model; for partial-year eligibility see IRS Publication 969.
Worked example
Family HDHP all 12 months with a 8,550 limit, age 55 with a 1,000 catch-up, 2,000 already contributed. Prorated base = 8,550. Total limit = 9,550. Remaining room = 7,550.00.
HSA limits: frequently asked questions
How much can I contribute to an HSA?
The IRS sets an annual HSA contribution limit each year, with a higher limit for family high-deductible health plan (HDHP) coverage than for self-only coverage. People age 55 or older by year-end can add a catch-up contribution. Because these dollar figures are indexed and change yearly, this calculator takes the self-only limit, family limit and catch-up amount as editable inputs from the current IRS revenue procedure.
What is the last-month rule and proration?
If you are HDHP-eligible on December 1, the last-month rule lets you contribute the full annual limit and stay eligible through a testing period. Otherwise, your limit is prorated by the number of months you had HDHP coverage on the first of the month, divided by 12. This calculator lets you enter eligible months to prorate the limit.
Who is eligible for the age-55 catch-up?
If you are 55 or older by the end of the tax year and covered by an HDHP, you can contribute the catch-up amount on top of the standard limit. The catch-up is per person, so spouses who are both 55 or older each need their own HSA to claim it. Enter the catch-up amount and tick that you qualify.
What happens if I contribute too much?
Excess HSA contributions are subject to a 6% excise tax for each year they remain in the account. You can avoid the tax by withdrawing the excess (and any earnings on it) before the tax filing deadline. This calculator shows your remaining room so you can stay within the limit.
Official sources
- Internal Revenue Service: About Publication 969, Health Savings Accounts and Other Tax-Favored Health Plans.
- Internal Revenue Service: About Form 8889, Health Savings Accounts (HSAs).
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.