Administrator guide · checked August 2026

Letter of Medical Necessity for a Fidelity HSA

Fidelity’s eligible-expense guidance allows gym memberships with a Letter of Medical Necessity — with one rule people miss: the membership should not predate the physician’s recommendation. A membership you already had is treated as something you were paying for anyway; the letter needs to come first.

What Fidelity requires

  • A Letter of Medical Necessity tying the membership to a diagnosed condition
  • The letter dated BEFORE the membership period you reimburse (the timing rule)
  • Records: the letter plus itemized receipts, kept in case of IRS review

The steps, in order

  1. Get the letter before you buy or renew the membership
  2. Pay out of pocket — gym terminals typically decline benefits cards
  3. Reimburse yourself from the HSA (Fidelity HSAs are self-substantiated: no upfront claim review)
  4. Keep the letter and receipts — with an HSA, the documentation is tested at IRS review, not at withdrawal

Source: Fidelity: HSA and FSA eligible expenses. Policies change and employer plan designs vary — your administrator makes the final reimbursement decision. This page is general information, not tax or medical advice.

Need the letter itself?

A board-certified physician reviews your health profile and, when clinically appropriate, issues a signed Letter of Medical Necessity the same day — with the diagnosis, ICD-10 code, duration, NPI and license your administratorlooks for. $69, full refund if a letter isn’t issued. The eligibility check is free.

Check if I qualify →

Common questions

Why does it matter that my membership predates the letter?

The IRS test is whether the expense exists because of the medical condition. A membership you already carried fails that test for the months before the letter existed. Reimburse from the letter’s date forward.

Fidelity didn’t review my withdrawal — am I approved?

No. HSA withdrawals usually aren’t reviewed upfront; the expense is only tested if the IRS looks. That is exactly why the letter needs to be genuinely solid, not just to exist.

Does this apply to a Fidelity FSA too?

FSAs are substantiated upfront, so a weak letter fails fast. The same letter standard — diagnosis, expense, duration, signature — covers both.

Keep reading
The complete Letter of Medical Necessity guide (2026)Is a gym membership HSA/FSA eligible?What qualifies for an LMN: the full catalog