Understanding HSA Expense Eligibility Rules

You searched to see whether something is HSA-eligible. One website said yes. Another said it depends. A third said you need a Letter of Medical Necessity. Confused?

This is common, and the frustrating part is that all of those answers can technically be correct at the same time — depending on the item and your situation. Once you understand where the rules come from, hopefully you'll understand the difference.

The short version: HSA rules start with Congress — specifically IRC Section 213(d), which establishes the legal definition of a qualified medical expense. The IRS issues guidance through Publications 502 and 969 explaining how to apply that law. Different sources and professionals may interpret that guidance differently. Some items are not universally eligible for everyone — the answer depends on your situation, your medical history, and the specific expense.

Congress Writes the Law, The IRS Explains It, HSA Others Interpret It

HSAs are a federal tax benefit governed by federal tax law. The legal foundation to which everything else traces back is IRC Section 213(d), part of the Internal Revenue Code — federal legislation passed by Congress.

This is the actual statute that defines what a "qualified medical expense" means under US tax law. It says medical expenses include costs related to the diagnosis, cure, mitigation, treatment, or prevention of disease, or for the purpose of affecting any structure or function of the body.

The IRS is the agency responsible for enforcing that law and issuing guidance on how it applies in practice. Publication 502 includes a detailed list of what qualifies and what doesn't — but it cannot anticipate every product on the market.

When items fall outside that list, administrators, retailers, benefits platforms, and websites like this one interpret that guidance for specific products and situations.

Reasonable sources can land in different places on the same item — and that difference is not necessarily wrong or right. It reflects varying interpretations of the same IRS guidance. In the end, however, the IRS is the only authoritative source

The Three Sources That Matter Most

For HSAs, three documents do most of the work:

1. IRC Section 213(d) — The federal law, written by Congress, that defines a qualified medical expense. Everything else traces back here.

2. IRS Publication 502 — The IRS's plain-English guide to what counts as medical care under that definition. The most practical reference for everyday eligibility questions.

3. IRS Publication 969 — The HSA-specific guide. Covers contribution limits, eligibility rules, tax treatment, and penalties — and points back to Publication 502 for the medical expense definitions.

Click here to view all the HSA-relevant IRS sources, updates, and forms.

The Three Eligibility Categories You'll See

Once you understand the source hierarchy, the eligibility landscape basically sorts into three buckets:

Automatically Eligible — Expenses that clearly fit the IRS definition of medical care under Publication 502, and are not already reimbursed elsewhere. Prescription medications, insulin, blood pressure monitors, eyeglasses, dental care, bandages, and more. In straightforward cases, you can pay directly with your HSA card or reimburse yourself. No additional documentation is needed.

LMN Required — Items that fall into a gray area not specifically addressed in IRS Publication 502. A Letter of Medical Necessity from a licensed healthcare provider is required, and the expense must still meet IRS guidelines under IRC Section 213(d). When in doubt, refer to IRS Publication 502 or consult a qualified professional.

Not eligible — General health and wellness. Gym memberships, vitamins for general health, cosmetics, toiletries. The IRS draws a clear line between treating a medical condition and maintaining general well-being.

Use our HSA Eligible Expense Search Tool to browse different types of eligible items.

The Bottom Line

HSA rules start with Congress, are explained by the IRS, and are interpreted differently by various sources. Once you understand that chain, the conflicting answers you find online start to make a lot more sense.

When in doubt, go straight to IRS Publications 502 and 969 as your primary reference. That is the most reliable path to a confident answer.

---

Thanks for reading, The Saving Wiser Team

Sources:

• IRC Section 213(d) — Internal Revenue Code

• IRS Publication 502 — Medical and Dental Expenses

• IRS Publication 969 — Health Savings Accounts and Other Tax-Favored Health Plans

This content is for informational purposes only and does not constitute tax, legal, financial, or medical advice. We make every effort to verify the accuracy of the information provided; however, HSA eligibility rules and IRS guidelines can and do change. For questions about HSA eligibility, refer to IRS Publication 502 and IRS Publication 969 directly, or consult a licensed tax professional, financial advisor, or qualified healthcare provider.