Form 8889 is how you report Health Savings Account activity to the IRS, and you fill it out in three parts: Part I handles contributions and your deduction, Part II handles distributions and any tax on non-qualified withdrawals, and Part III handles recapture if you used the last-month rule and later lost eligibility. You attach the finished form to your Form 1040, 1040-SR, or 1040-NR for any year the HSA had contributions, distributions, a failed testing period, or an inherited interest.
When You Have to File It
File a Form 8889 for each account holder whenever any of these happened during the year:
- Contributions went into the HSA from you, your employer, or anyone else, including pretax payroll contributions through a cafeteria plan.
- You took any distribution, whether it went to a provider or into your checking account.
- You failed a testing period tied to a prior-year last-month rule contribution.
- You acquired an interest in someone else’s HSA because the account holder died.
The requirement stands even if you would not otherwise have to file a return.
If you and your spouse file jointly and each of you has an HSA, each of you completes a separate Form 8889 and both get attached to the joint 1040. One form per account holder.
One boundary worth flagging: when a non-spouse inherits an HSA, the account stops being an HSA on the date of death and the full fair market value is taxable income to the beneficiary that year, reduced by any qualified medical expenses of the deceased that the beneficiary pays within a year. A spouse who inherits simply keeps the account as their own.
What to Pull Together First
Have these in front of you before you open the form:
- Form 1099-SA from your HSA custodian, which shows total distributions in Box 1. Custodians send this by January 31.
- Form 5498-SA, which shows total contributions including employer amounts. It can arrive as late as May, so if you’re filing early you may need to work from your own records or December statements.
- Form W-2, Box 12, Code W. That figure combines your employer’s contributions and any pretax payroll contributions you made through a cafeteria plan.
- Receipts for the medical expenses you paid from the HSA. You don’t submit these, but keep them for at least three years from the filing date.
You also need to know which months of the year you were covered by a qualifying high-deductible health plan and whether that coverage was self-only or family. That month-by-month picture drives your contribution limit.
Part I: Contributions and the Deduction
Part I calculates how much of your HSA contribution is deductible. The deduction lands on Schedule 1 of Form 1040 and reduces your adjusted gross income.
Line 1. Check self-only or family. If you switched between the two during the year, use the one that covered you longer. If you had both simultaneously at any point, treat that overlap as family coverage.
Line 2. Enter your personal contributions for the tax year. Include deposits you made directly and any contributions made between January 1 and the April filing deadline that you designate for the prior tax year. Do not include employer or cafeteria plan contributions on this line.
Line 3. Enter your contribution limit. If you were eligible all 12 months with one coverage type, this is just the annual maximum for that coverage: for the 2026 tax year, Rev. Proc. 2025-19 sets it at $4,400 for self-only and $8,750 for family. Add $1,000 if you’re 55 or older by year-end. If your eligibility or coverage type changed mid-year, use the Line 3 Limitation Chart and Worksheet in the instructions to prorate month by month. The last-month rule can override that proration if you were an eligible individual on December 1.
Two eligibility points affect Line 3 more than any others. Your plan qualifies as an HDHP in 2026 only if the annual deductible is at least $1,700 self-only or $3,400 family, with out-of-pocket expenses capped at $8,500 or $17,000 respectively. And starting the first month you’re enrolled in Medicare, your contribution limit for that month is zero. Retroactive Medicare coverage counts, so contributions made during a backdated period become excess.
Line 9. Enter employer contributions from W-2 Box 12, Code W. This already includes any pretax cafeteria plan amounts you elected. Those got favorable tax treatment through payroll, so they reduce what you can deduct on the return.
Line 13. Your HSA deduction. Generally it’s the smaller of Line 2 or your remaining limit after subtracting the Line 9 employer contributions. Carry it to Schedule 1.
Part II: Distributions
Part II decides whether any of the money you withdrew is taxable.
Line 14a. Total distributions from all your HSAs, from Form 1099-SA Box 1.
Line 14b. Amounts that shouldn’t count as regular distributions: rollovers to another HSA, and excess contributions (with their earnings) that you withdrew by the filing deadline.
Line 15. Total qualified medical expenses you paid with HSA funds. Only include expenses not reimbursed by insurance or another source and not claimed as an itemized deduction. Qualified expenses can cover you, your spouse, and your dependents. Publication 502 defines the category, which broadly includes doctor visits, hospital care, prescriptions, dental and vision care, and many over-the-counter items; premiums generally don’t count, with narrow exceptions for COBRA, long-term care insurance, and coverage during unemployment.
Line 16. The difference between net distributions and qualified expenses. Anything left over is taxable income and flows to Schedule 1.
Lines 17a and 17b. The 20% additional tax on the taxable portion. Three exceptions remove the penalty: reaching age 65, becoming disabled, or distributions made after the account holder’s death. Check the box on Line 17a if an exception applies and calculate the 20% only on the amount not covered by an exception. After 65, non-medical withdrawals are still ordinary income but carry no penalty.
Part III: Last-Month Rule Recapture
Skip Part III unless you used the last-month rule in a prior year and then lost eligibility before the testing period ended.
The last-month rule treats you as eligible for the whole year if you were eligible on December 1, letting you contribute the full annual limit. In exchange, you have to stay eligible from that December 1 through December 31 of the next year — 13 months. If you drop HDHP coverage, enroll in Medicare, or otherwise lose eligibility during that window for any reason other than death or disability, the extra contributions you made under the rule become taxable income in the year you lost eligibility, plus a 10% additional tax. Part III is where you calculate both.
Fixing Excess Contributions
If your contributions plus your employer’s exceeded the Line 3 limit, you have excess contributions. The clean fix is to withdraw the excess and any earnings on it before your filing deadline, including extensions. The custodian reports the withdrawal on Form 1099-SA, and you back it out on Part II so it isn’t double-counted.
Miss that deadline and the excess stays in the account, triggering a 6% excise tax each year it remains. That tax gets reported on Form 5329, not on Form 8889. The 6% applies to the excess amount or 6% of the year-end account value, whichever is less. You can absorb the excess later by contributing under your limit in a future year and letting the unused room soak it up.
Filing the Form
Attach Form 8889 to your Form 1040, 1040-SR, or 1040-NR. Tax software builds the form from the HSA figures you enter and transmits it with the return. On a paper filing, place Form 8889 behind the main return.
The filing deadline is April 15. The automatic extension to October 15 gives you more time to file the return but does not extend the deadline for prior-year HSA contributions, which must still be deposited by April 15. If you already filed and realize you left Form 8889 off, file Form 1040-X with the missing 8889 attached before an IRS notice arrives.