HSA limits · proration · IRS Pub 969
How much can you put in your HSA?
Not eligible all year? Your HSA limit is prorated by eligible months. The last-month rule can restore the full limit — but starts a 13-month testing period.
Open the full calculator ↗2026 & 2025 figures
| Item | 2026 | 2025 |
|---|---|---|
| Self-only limit | $4,400 | $4,300 |
| Family limit | $8,750 | $8,550 |
| Age-55+ catch-up | $1,000 | $1,000 |
| HDHP min deductible (self/family) | $1,700/$3,400 | $1,650/$3,300 |
How it works
Eligibility is monthly (HDHP on the 1st, no other coverage). Prorated limit = annual limit x eligible months / 12; the $1,000 catch-up prorates the same way. Eligible on December 1 -> the last-month rule lets you contribute the full year, subject to the testing period.
Questions
You are HSA-eligible for a month if you have qualifying HDHP coverage on the first day of that month and no disqualifying coverage. If you are not eligible all year, your base limit is the annual amount times the number of eligible months divided by 12. The age-55+ catch-up ($1,000) is prorated the same way, and HSAProrate does that math for both.
If you are HSA-eligible on December 1, the last-month rule lets you contribute the full annual limit for that December coverage type, even if you were not eligible earlier in the year. It is optional — you can also just contribute the prorated amount with no strings attached.
If you use the last-month rule, you must stay HSA-eligible for the entire following calendar year — the testing period runs from December 1 of the contribution year through December 31 of the next year. If you lose eligibility during it (other than death or disability), the extra amount you contributed above the prorated limit is added back to your taxable income and hit with an additional 10% tax. HSAProrate shows exactly how much is at risk.
Yes. The IRS limit is the combined total of what you, your employer, and anyone else put into your HSA for the year. Enter what has already gone in (including employer and payroll contributions) to see how much room you have left.
The family contribution limit is shared and can be split between spouses in any way you agree. But each $1,000 age-55+ catch-up must go into that spouse's own HSA — you cannot combine both catch-ups in one account. This tool calculates one person's figures at a time.
You can make HSA contributions for a tax year up to the federal tax-filing deadline of the following April (without extensions) — for 2026 that is April 15, 2027. Just tell your HSA custodian which tax year the contribution is for.