What are these accounts?
Health savings account is the full name behind HSA. For FSA, the full name is flexible spending arrangement. They let eligible people save for medical bills before tax is taken out.
Ask the person who runs your account which records they need for this expense.
Does a general wish for more energy count?
The IRS is the federal tax agency. A diagnosis means a health professional has identified a condition.
As of September 2026, IRS guidance distinguishes treating a diagnosed disease from spending only to improve general health.
In September 2026 guidance, the IRS allowed weight-loss costs to treat a specific disease diagnosed by a doctor; weight loss alone was not enough.
Ask how the rule applies to the actual expense.
What is a medical-need letter?
It is a note explaining why an expense is needed for care. The person or company managing your account may ask for that note.
The IRS guidance checked in September 2026 did not call for a “letter of medical necessity”; the rules for your account may still ask for that note.
The account may still need records showing what the expense was for, when it happened and how much it cost. Ask the person running it what to send before paying.
What can I keep with the receipt?
Ask it like this
- Which parts of this bill can the account reimburse?
- What records show the medical purpose?
- Does the person running my account need a letter?
- What details need to appear on the receipt?
A reimbursement is money paid back for an expense. Getting a receipt and a plan answer is more useful than trusting a general “eligible” badge.