HSA Tax Form 8889: Who Files and What to Report

To report a Health Savings Account on your tax return, attach IRS Form 8889 to your Form 1040. That single form handles everything: it tallies contributions, calculates your deduction, and reconciles any distributions against the medical expenses you paid. The deductible amount then flows to Schedule 1 as an above-the-line adjustment, which lowers your adjusted gross income whether you itemize or take the standard deduction.¹

When You Have to File Form 8889

The filing trigger is broader than most people expect. You must attach the form to your return if any of the following happened during the year: you or your employer put money into your HSA, you took any distribution from the account, you inherited someone else’s HSA, or you used the last-month rule in a prior year and failed the testing period.¹

Even if your only HSA activity was employer contributions that never appeared in your taxable wages, you still file. Skipping the form when it’s required can trigger IRS notices and delay your refund.

Documents You Need Before You Start

Two forms from your HSA custodian carry the numbers you’ll transcribe onto Form 8889.

Form 1099-SA reports every distribution. Box 1 shows the total withdrawn, and Box 3 carries a distribution code: 1 for a normal distribution, 2 for an excess contribution removal, and other codes for disability or death. The code tells the IRS what kind of withdrawal it was, but it does not decide whether the money is taxable. That turns on whether you actually spent it on qualified medical expenses, and proving that is on you. Keep the receipts indefinitely. You don’t send them with your return, but you need them if the IRS asks.²

Form 5498-SA reports contributions. Box 2 shows the combined amount put in by you and your employer during the calendar year.³ This one often arrives late, because prior-year contributions can be made all the way up to the April filing deadline. If you file before it arrives, use your own records.

Also pull out your W-2. Any contributions your employer made, including anything you routed in through a Section 125 cafeteria plan payroll deduction, appear in Box 12 with code W.⁴ Those dollars were already excluded from your wages, so they don’t get deducted again on Form 8889, but they do count against your annual limit.

Part I: Contributions and the Deduction

Part I calculates how much you can deduct. It starts with your annual limit, subtracts what your employer already excluded from wages, and lands on the amount that reduces your income.

Your Annual Contribution Limit

For 2026, the ceiling is $4,400 for self-only HDHP coverage and $8,750 for family coverage. If you are 55 or older and not on Medicare, you can add a $1,000 catch-up. That catch-up is fixed by statute and does not adjust for inflation.⁵

Prorating When You Weren’t Covered All Year

If you didn’t have HDHP coverage for the whole year, your limit is generally prorated by the number of months you were an eligible individual on the first day of the month, divided by 12. Enroll on March 15 and your eligible months start in April, because you weren’t covered on March 1.

The last-month rule is the escape hatch. If you are eligible on December 1, the IRS treats you as eligible for the whole year and lets you contribute the full annual limit.⁶ The condition: you must remain an eligible individual through December 31 of the following year. Break that testing period and the extra amount you contributed above the prorated limit gets added back to your taxable income for the year you lose coverage, plus a 10% additional tax. That calculation happens in Part III of Form 8889.¹

Employer Money vs. Your Own Money

How the money reached the account decides what gets deducted. Employer contributions and payroll-deducted cafeteria plan contributions were never in your wages, so they can’t be deducted a second time. You list them on Form 8889 to account against your limit, but they don’t produce a line 2 deduction.

Contributions you made directly, outside payroll, go on line 2. Those are the ones that generate the HSA deduction. As long as everything combined stays inside your annual limit, your direct contributions are fully deductible.¹

Where the Deduction Ends Up

The amount on line 13 of Form 8889 carries over to Schedule 1 of your Form 1040 as an adjustment to income.¹ Because it’s above the line, it works whether or not you itemize, and a lower AGI can help you qualify for other benefits that phase out at higher income.

Part II: Distributions and What’s Taxable

Part II reconciles what you took out against what you spent on qualified medical care. The math is simple; the consequences of getting it wrong are not.

What Qualifies as a Medical Expense

Qualified medical expenses generally match what would be deductible on Schedule A: doctor visits, prescriptions, dental work, vision care, lab tests, and similar out-of-pocket costs.⁷ Health insurance premiums are mostly excluded, with narrow exceptions for COBRA, long-term care insurance, and Medicare premiums paid after 65. Costs that are just generally healthful, like gym memberships or vitamins, don’t count.

Adding Up the Numbers

Take the Box 1 total from your 1099-SA and compare it to your qualified medical expenses for the year. If your expenses equal or exceed your distributions, every dollar is tax-free. That amount goes on line 15 and nothing flows into your taxable income.¹

If distributions exceed qualified expenses, the difference is a non-qualified distribution. It goes on line 16 and gets added to your taxable income on Form 1040.

The 20% Additional Tax

Non-qualified distributions carry a 20% additional tax on top of ordinary income tax. It’s calculated on line 17b of Form 8889 and reported on Schedule 2.⁸ Combined with a high marginal rate, that penalty can consume close to half of what you withdrew.

Three situations remove the 20% penalty:

You are 65 or older. Non-qualified distributions are still taxed as ordinary income, but the additional tax no longer applies.
You became disabled as defined under federal tax law.
The distribution was made after the account holder’s death.

Excess Contributions Go on a Different Form

If total contributions exceeded your limit, the overage is subject to a 6% excise tax for every year it stays in the account.⁹ That penalty isn’t reported on Form 8889. It goes on Part VII of Form 5329.¹⁰ Form 8889 identifies the excess; Form 5329 taxes it.

You can avoid the 6% tax completely by pulling the excess, plus any earnings on it, before your filing deadline including extensions. For an extended return, that’s October 15. Your custodian issues a corrected 1099-SA, and the earnings withdrawn with the excess are taxable in the year of the withdrawal. Miss the deadline and the 6% is due; the excess also carries forward, and the penalty keeps hitting each year until you either withdraw the amount or absorb it with unused contribution room in a later year.

The Medicare Cutoff to Watch

Enrollment in Medicare Part A or Part B ends your ability to contribute to an HSA. The disqualification starts the month your Medicare coverage begins, not the month you sign up.

The trap is retroactivity. If you qualify for premium-free Part A (most people who worked at least 10 years) and delay enrollment past 65, your Part A coverage backdates up to six months when you finally enroll. That backdating can turn months of legitimate HSA contributions into excess contributions subject to the 6% tax. If you plan to enroll after 65, stop contributing at least six months before your enrollment date.

You can still spend the balance already in the account after Medicare kicks in. Distributions for qualified medical expenses remain tax-free, and qualifying costs include Medicare premiums, deductibles, and copayments. You just can’t add new money.

1
Internal Revenue Service. Instructions for Form 8889
2
Internal Revenue Service. Form 1099-SA – Distributions From an HSA, Archer MSA, or Medicare Advantage MSA
3
Internal Revenue Service. Form 5498-SA – HSA, Archer MSA, or Medicare Advantage MSA Information
4
Internal Revenue Service. Form W-2 Reporting of Employer-Sponsored Health Coverage
5
Internal Revenue Service. Revenue Procedure 2025-19
6
Internal Revenue Service. IRS Publication 969 – Health Savings Accounts and Other Tax-Favored Health Plans
7
Internal Revenue Service. IRS Publication 502 – Medical and Dental Expenses
8
Office of the Law Revision Counsel. 26 U.S. Code 223 – Health Savings Accounts
9
Office of the Law Revision Counsel. 26 U.S. Code 4973 – Tax on Excess Contributions to Certain Tax-Favored Accounts and Annuities
10
Internal Revenue Service. Instructions for Form 5329