Medicare and Health Savings Accounts (HSAs) have a complex relationship, particularly due to IRS rules that link HSA eligibility to “disqualifying” coverage like Medicare. For the 2026 tax year, new contribution limits and legislative updates have shifted the landscape for those transitioning between the two.

The 2026 HSA Contribution Limits

If you are eligible for an HSA in 2026, the IRS has increased the amount you can contribute.

  • Self-Only Coverage: $4,400 (up from $4,300 in 2025).
  • Family Coverage: $8,750 (up from $8,550 in 2025).
  • Catch-Up Contribution: Individuals age 55 and older can contribute an additional $1,000. Note that this catch-up is per person, so if both spouses are 55+, they must each have their own HSA account to contribute a full $1,000 each.

The Enrollment Conflict

The most critical rule remains: You cannot contribute new money to an HSA once you are enrolled in any part of Medicare (Part A, B, C, or D).

  • The “Drop to Zero” Rule: The moment your Medicare coverage begins, your allowed HSA contribution for that year must be prorated. If you enroll in Medicare on July 1, 2026, you can only contribute 50% of the annual limit.
  • Social Security Link: If you begin taking Social Security benefits, you are automatically enrolled in Medicare Part A. This immediately terminates your ability to contribute to an HSA.

The 6-Month Lookback Rule

This is the most common trap for people who work past age 65. If you delay Medicare enrollment and then apply later (e.g., at age 67), your Part A coverage is backdated six months.

  • The Risk: If you contribute to your HSA during those six months of retroactive Medicare coverage, those contributions become “excess contributions” subject to a 6% excise tax every year they remain in the account.
  • Proactive Strategy: To avoid this, experts recommend stopping all HSA contributions at least six months before you submit your Medicare application if you are already over age 65.

Using Your HSA After Medicare

While you cannot add money, your existing HSA funds remain one of your most powerful retirement tools.

  • Paying Premiums: You can use HSA funds tax-free to pay for Medicare Part B, Part C (Advantage), and Part D premiums.
  • The Exception: You cannot use HSA funds tax-free to pay for Medigap (Supplement) premiums.
  • The 65+ Rule: Once you turn 65, the 20% penalty for non-medical withdrawals disappears. You can use HSA money for anything (like a vacation), though you will pay ordinary income tax on those non-medical distributions, similar to a Traditional IRA.

2026 “OBBB Act” Updates

The “One Big Beautiful Bill” Act has introduced a significant expansion for HSA eligibility in 2026.

  • Bronze and Catastrophic Plans: Previously, many ACA Marketplace plans did not qualify as High-Deductible Health Plans (HDHPs) due to their structure. Starting in 2026, Bronze and Catastrophic plans are now officially HSA-compatible.
  • Telehealth Safe Harbor: The provision allowing HDHPs to cover telehealth services before the deductible is met has been made permanent as of 2026.

Source: IRS Revenue Procedure 2025-19 (May 2025); IRS Notice 2026-05 (Dec 2025); and SSA Publication 05-10043.