What this calculator does
Find out how much you can put into a health savings account (HSA) for 2026, and how much tax it saves you. An HSA is a savings account for medical costs. You can have one only if you're covered by a high-deductible health plan, a plan with a larger deductible than most.
HSAs have three tax breaks. Money goes in before income tax. It grows without yearly tax. And it comes out tax-free when you spend it on qualified medical costs. The calculator finds your limit for full or partial years, then shows the tax saved. It can also project the balance over the years. The result is an estimate, not tax advice.
Where it's used
Why this math matters outside the classroom:
- Open enrollment. An employee compares plans and sees that a $4,400 HSA contribution through payroll at 29.65% saves $1,304.60.
- Starting mid-year. A new hire covered for 5 months of 2026 can put in $4,400 × 5 ÷ 12, which is $1,833.33.
- Planning at 55. A 56-year-old with family coverage adds the $1,000 catch-up, raising the 2026 limit to $9,750.
- Budgeting for health costs. A saver invests $4,400 a year at 5% for 10 years and projects about $55,342.73 for later medical bills.
Grade level and standards: Grade 7; Common Core State Standards for Mathematics 7.RP.A.3. © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
How to use it
- Choose self-only or family coverage, and tick the box if you're 55 or older by the end of 2026.
- Enter how many months you had the plan. Add any money your employer puts in and, if you like, the amount you plan to put in.
- Choose whether you contribute through payroll or on your own, and enter your tax rates.
- To see growth, enter a starting balance, a number of years and a yearly return.
What the inputs mean
- Your high-deductible health plan covers
- Self-only means the plan covers just you. Family means it covers you and at least one other person. For 2026 the limits are $4,400 and $8,750.
- I'm 55 or older by December 31, 2026 (+$1,000 catch-up)
- If you're 55 or older on December 31, you can add $1,000 a year. Married couples who both qualify must each put their catch-up in their own HSA.
- Months covered in 2026
- Count each month you had the plan on the first day, with no other health coverage. Enrolling in Medicare ends your eligibility. For a partial year, you get one twelfth of the yearly limit for each month.
- I was covered on December 1 and will use the last-month rule
- If you were covered on December 1, you can treat yourself as covered all year. The catch is a testing period. You must stay eligible through December 31 of the next year. Otherwise the extra is taxed, plus a 10% additional tax.
- Employer contributions (optional)
- Your employer's money counts toward the same yearly limit. It's tax-free to you, so it's not part of the tax saved shown here.
- Your contribution (optional)
- Leave blank to use all the room you have left.
- How you put money in
- Money taken from your pay through a workplace plan skips Social Security and Medicare as well as income tax. Money you put in yourself is deducted on your return, which only saves income tax.
- Your federal tax bracket
- Your marginal rate: 10, 12, 22, 24, 32, 35 or 37.
- State income tax rate (optional)
- Most states follow the federal rule. A few, such as California and New Jersey, tax HSA contributions. If you live in one of them, enter 0 here.
- Social Security and Medicare rate saved
- Social Security is 6.2% and Medicare is 1.45%, for 7.65%. If your pay is over the $184,500 Social Security wage base for 2026, only the 1.45% applies to more pay.
Formula and method
yearly limit = $4,400 self-only or $8,750 family, + $1,000 if 55 or older your limit = yearly limit × months covered ÷ 12 (all 12 under the last-month rule) room left = your limit − employer contributions tax saved = your contribution × (federal rate + state rate + 7.65% if through payroll) balanceₜ₊₁ = balanceₜ × (1 + r) + yearly deposit
These 2026 limits come from IRS Rev. Proc. 2025-19. The $1,000 catch-up is set in the law and doesn't change with inflation. For a partial year, the IRS counts each month you were covered on the first day, then divides by 12.
The tax saved uses your marginal rate, the rate on your last dollar of income. That's the rate an HSA contribution avoids. Your bracket is a good stand-in.
In the growth formula, r is the yearly return as a decimal (5% is 0.05). balanceₜ is the balance after year t. The deposit is your contribution plus your employer's, added at the end of each year. Returns compound once a year.
Worked example
You have self-only coverage all of 2026, contribute through payroll, are in the 22% bracket and have no state income tax. You invest it for 10 years at 5% a year.
- Your 2026 limit: $4,400 for self-only coverage, all 12 months.
- Rate saved: 22% federal + 7.65% Social Security and Medicare = 29.65%.
- Tax saved: $4,400 × 29.65% = $1,304.60. So the $4,400 really costs you $3,095.40.
- Ten yearly deposits of $4,400 at 5% grow to $55,342.73. That's $44,000 of deposits plus $11,342.73 of growth.
Result: You can put in $4,400 for 2026, saving about $1,304.60 in tax. Kept invested for 10 years, the account could hold about $55,342.73.
Understanding the result
Your limit is the most that can go in for 2026 from you and your employer together. Going over it means a 6% excise tax each year until you take the extra out.
The tax saved shows why payroll contributions are worth more. Skipping Social Security and Medicare adds 7.65% to the saving for most people.
The growth projection assumes you pay medical bills from other money and leave the HSA invested. Many people do this to build a fund for health costs later in life.
Assumptions and limitations
- It uses the 2026 HSA limits from IRS Rev. Proc. 2025-19: $4,400 self-only and $8,750 family, plus a $1,000 catch-up at 55.
- Tax rates are flat rates you enter. The saving uses your contribution only, at those rates.
- The projection adds the same deposit at the end of each year and earns one steady yearly return. Limits are held at 2026 levels.
- This is an estimate, not tax or medical advice. Check the IRS rules or ask a tax professional before you contribute.
- It doesn't check whether your health plan qualifies. For 2026, a high-deductible plan needs a deductible of at least $1,700 self-only or $3,400 family.
- It doesn't cover splitting a family limit between spouses, the 20% penalty for non-medical withdrawals before 65, or one-time transfers from an IRA.
Frequently asked questions
What is the HSA contribution limit for 2026?
It's $4,400 for self-only coverage and $8,750 for family coverage. If you're 55 or older by the end of the year, you can add $1,000. Employer money counts toward these limits.
What if I only had a high-deductible plan for part of the year?
You get one twelfth of the yearly limit for each month you were covered on the first day. With self-only coverage for 5 months, that's $4,400 × 5 ÷ 12 = $1,833.33. If you were covered on December 1, the last-month rule can give you the full limit, with a testing period.
Is it better to contribute through payroll?
Usually, yes. Payroll contributions skip Social Security and Medicare, 7.65% for most workers. Contributions you make yourself only save income tax, because you deduct them on your return.
What happens to my HSA if I change jobs or plans?
The money is yours and stays in the account. You can keep spending it on qualified medical costs. You just can't add more in months when you're not covered by a high-deductible plan.
Can I use HSA money for things other than medical costs?
You can, but it's taxed as income. Before 65 there's also a 20% penalty. From 65 on, the penalty goes away, so the account works much like a traditional IRA for non-medical spending.
Sources
- IRS Rev. Proc. 2025-19, 2026 inflation adjusted amounts for HSAs (checked 2026-10-26)
- IRS Publication 969, Health Savings Accounts and Other Tax-Favored Health Plans (checked 2026-10-26)
How this calculator is checked
Method: 2026 HSA limits from IRS Rev. Proc. 2025-19 and the statutory $1,000 catch-up (IRC 223(b)(3)(B)); monthly proration per the Form 8889 line 3 and line 7 worksheets; last-month rule per IRS Pub. 969. Tax saved as contribution × entered rates; yearly future-value recursion. The calculation is covered by automated tests with known reference values and edge cases. Last updated 2026-10-26. Found a problem? Tell us.
Embed this calculator
Put this HSA Calculator on your own website or blog for free. Paste this code where you want it to appear: