HSA contribution calculator

What is the HSA contribution limit for 2026?

$4,400 with self-only coverage and $8,750 with family coverage (IRS Rev. Proc. 2025-19). If you are 55 or older by the end of the year you can add $1,000; that catch-up is set by law and is not adjusted for inflation. Everything paid in counts — yours, your employer’s, and payroll contributions through a cafeteria plan, which the IRS treats as employer contributions.

What counts as a high-deductible health plan in 2026?

A deductible of at least $1,700 (self-only) or $3,400 (family), and out-of-pocket costs capped at no more than $8,500 or $17,000. Under the One, Big, Beautiful Bill Act, from January 1, 2026 bronze and catastrophic plans available as individual coverage through an Exchange count as HSA-compatible even if they miss those numbers (IRS Notice 2026-5), and a direct primary care arrangement costing no more than $150 a month ($300 for more than one person) no longer blocks HSA contributions.

What if I was covered for only part of the year?

The limit is figured month by month: you count a month if you were HSA-eligible on the first day of it, and the yearly limit is prorated. Example: self-only coverage for 7 months is $4,400 × 7 ÷ 12 = $2,566.67. Months you are enrolled in Medicare count as zero.

What are the last-month rule and the testing period?

If you are eligible on December 1, IRS Publication 969 treats you as eligible for the whole year, so you can put in the full limit. The catch: you must stay eligible through the testing period — December 1, 2026 to December 31, 2027. If you do not (other than because of death or disability), the amount you could only contribute because of this rule is added to your income, plus a 10% additional tax.

How much tax does an HSA save?

Contributions you make yourself are deducted from income; contributions through your employer are left out of your taxable pay. The calculator multiplies the room left by the federal tax rate you choose — a rough estimate. It leaves out state taxes, and payroll contributions generally also avoid employment taxes.

When is the deadline to contribute for 2026?

Contributions for a tax year can be made until the due date of your return for that year, without extensions, which is generally April 15 of the following year (IRS Publication 969). Tell your HSA custodian which year a contribution belongs to, otherwise it may be booked to the year in which it is received.

How is the family limit shared between spouses?

If both spouses have HSAs and are covered by family HDHP coverage, the family limit is split equally unless they agree to divide it differently. Each spouse who is 55 or older adds the catch-up contribution, and it has to go into that spouse’s own HSA. The family limit is not doubled.

What happens if I put in too much?

The excess is generally subject to a 6% excise tax for each year it stays in the account. You can avoid the tax by withdrawing the excess and its earnings by the due date of your return, including extensions; the earnings are included in your income for that year.

How the limit is built

Take the annual limit for your coverage type ($4,400 self-only, $8,750 family) and add the $1,000 catch-up if you turn 55 by year end. In a full year that is the limit. In a partial year it is that total times eligible months ÷ 12, unless the last-month rule applies. Everything paid in counts, employer money and payroll deductions included, so the room left is the limit minus the employer’s share. The tax estimate multiplies that room by the bracket you choose.

Worked examples

Family coverage all year, age 55 or older, $3,000 from the employer: $8,750 + $1,000 = $9,750. Subtract the $3,000 and $6,750 is still open. For a couple the catch-up has to go into the account of the spouse who is 55 or older.

Self-only coverage that began October 1, so 3 eligible months, with no last-month rule: $4,400 × 3 ÷ 12 = $1,100.00. If you are also covered on December 1 and use the last-month rule, the limit is the full $4,400, but you must stay eligible through the testing period or the part above $1,100.00 becomes taxable income plus a 10% additional tax.

Things to watch

• Count employer money. A payroll deduction through your employer’s plan is an employer contribution; adding it again to what you plan to put in yourself overstates the room.
• Medicare ends eligibility. From the first month you are enrolled your limit is zero, and Medicare coverage that is backdated can turn earlier contributions into excess ones. Check your enrollment date before contributing near age 65.
• Coverage type is figured by month. Switching from self-only to family mid-year changes the limit; this calculator assumes one type all year.

Estimates for planning only — not financial or tax advice. Official statements and your plan documents decide. How we check our calculators.

Sources: IRS Publication 969, Health Savings Accounts and Other Tax-Favored Health Plans (limits, married people, Medicare, deadlines, excess contributions); IRS Rev. Proc. 2025-19; IRS Notice 2026-5. Related tools: 401(k) calculator, income tax calculator, Roth IRA calculator.