Free Tool
HSA Contribution Calculator
$4,400 self-only or $8,750 family for 2026. Enter your age, months on an HDHP, and what you have already put in. Get your real prorated limit, your monthly target, and a warning if you have already gone over.
Your Situation
Coverage Type
55 or older? You get a $1,000 catch-up contribution.
You count a month if you were on the HDHP on the first of that month.
What you have already put in this year, including employer contributions.
How often you get paid. Used to calculate your per-paycheck contribution target.
HSA-eligible on December 1? Contribute the full annual limit. Requires staying eligible through December 31 of next year.
Your 2026 Contribution Limit
$4,400
$4,400 base, prorated for 12 of 12 months.
Remaining Contribution Room
$4,400
Limit minus what you have already contributed.
Monthly Target
$550.00
over 8 months left
Biweekly Target
$258.82
over 17 pay periods left
Last-Month Rule Scenario
Toggle this on if you will be HSA-eligible on December 1. It lets you contribute the full annual limit ($4,400) instead of the prorated amount. Costs you the 13-month testing period.
How the Math Works
The 2026 IRS limits are $4,400 for self-only HDHP coverage and $8,750 for family HDHP coverage. If you turn 55 by the end of the year, you can add another $1,000 catch-up contribution. That catch-up has to go into your own HSA, not your spouse's.
Proration is simpler than it sounds. Take the annual limit, divide by 12, and multiply by the number of months you were HSA-eligible. You count a month if you were on a qualifying HDHP on the first day of that month. Started family HDHP coverage on March 1? That is 10 months of eligibility, so your prorated limit is $8,750 times 10 divided by 12, or $7,292.
The Last-Month Rule
There is one exception to proration. If you are HSA-eligible on December 1, the IRS lets you contribute the full annual limit for the year, even if you only had coverage for part of it. This is the last-month rule. It is great in the short term and risky in the long term.
The trade is the testing period. You have to stay HSA-eligible from December 1 of the contribution year through December 31 of the following year. That is 13 months. If you drop your HDHP during that window, the amount you contributed above what proration would have allowed becomes taxable income. The IRS also adds a 10 percent additional tax on top of that, under IRC 223(b)(8). Use the last-month rule when you are confident your HDHP coverage will hold steady through the testing period.
Excess Contributions and the 6 Percent Tax
Going over your limit costs you. IRC 4973(g) charges a 6 percent excise tax on the excess every year it stays in your account. Put in $500 too much and forget about it for three years? That is $90 in penalties on top of whatever the $500 was supposed to do.
The fix is straightforward. Withdraw the excess plus any earnings it generated before your tax filing deadline, including extensions. Most HSA custodians have a one-page form for this. If you miss the deadline, you can apply the excess against next year's limit, but you keep paying the 6 percent every year until it is gone. Pull it out as soon as you notice.
Common Scenarios This Calculator Handles
Switched jobs mid-year? Your eligible months change based on when your HDHP coverage started and stopped. Married and both on HDHPs? The math depends on whether you have separate self-only coverage or shared family coverage. Turning 55 this year? Your limit jumps by $1,000 the year you hit that birthday, not the year after. All of these are built into the calculator above.
Want more context on the rules behind the numbers? Read the full breakdown of 2026 HSA contribution limits. If you are worried about getting any of this wrong, check the most common HSA mistakes and how to avoid them. Married? See the spouse-by-spouse contribution rules for couples. Halfway through the year? Run our mid-year HSA check-in. You can also project how those contributions grow over time with the HSA growth calculator.
Frequently Asked Questions
What are the 2026 HSA contribution limits?
For 2026, the HSA contribution limit is $4,400 for self-only HDHP coverage and $8,750 for family HDHP coverage. Anyone age 55 or older by the end of the year can add a $1,000 catch-up contribution. If both spouses are 55 or older and want the catch-up, each must put their $1,000 in their own HSA.
How do I prorate my HSA contribution if I was not on an HDHP all year?
Take your annual limit and multiply by the number of months you were HSA-eligible divided by 12. Example: family coverage for 7 months in 2026 is $8,750 times 7 divided by 12, which equals about $5,104. Eligibility is measured on the first of each month. If you were enrolled on the first, that month counts.
What is the HSA last-month rule?
The last-month rule lets you contribute the full annual limit if you are HSA-eligible on December 1. The catch is the 13-month testing period: you must stay HSA-eligible from December 1 through December 31 of the following year. Break that period and the part you would not have qualified for under proration becomes taxable income plus a 10 percent additional tax under IRC 223(b)(8).
What happens if I contribute too much to my HSA?
Excess contributions get hit with a 6 percent excise tax every year they sit in the account, under IRC 4973(g). To avoid it, withdraw the excess plus any earnings on it before your tax filing deadline (including extensions). Most HSA custodians have a simple form for this. Do not just leave it there hoping nobody notices.
Can both spouses contribute to an HSA?
Yes, but the rules depend on coverage. If both spouses have self-only HDHPs, each can contribute up to $4,400 to their own HSA. If one spouse has family HDHP coverage, the $8,750 family limit is shared and can be split however you want. Catch-up contributions for age 55+ must always go in each spouse's own HSA.
Are HSA contribution limits per person or per account?
The annual limit is per tax return, not per account. If you have three HSAs at three custodians, your combined contributions across all of them cannot exceed your annual limit. Catch-up contributions are the one exception. Those must go in your own HSA and cannot be combined with a spouse's.
Track Every Dollar
Track your HSA contributions in Tripl
The calculator tells you the limit. Tripl helps you actually hit it. Log every contribution, every receipt, and every reimbursement so you always know where you stand.
This is educational content, not financial or tax advice. Consult a qualified professional before making decisions about your HSA.
Brandon Nied is the founder of Tripl. He is not a CPA, CFP, or licensed financial advisor. This calculator is built for planning, not tax filing. Numbers verified against IRS Revenue Procedure guidance for 2026. Always confirm tax positions with a qualified professional.