A Health Savings Account (HSA) is an IRS-regulated, tax-advantaged savings account designed to help individuals with High-Deductible Health Plans (HDHPs) save for qualified medical expenses. Understanding HSA rules is essential for HR professionals, benefits administrators, financial advisors, payroll specialists, and anyone responsible for employee benefits programs.
HSA certification demonstrates your mastery of contribution limits, eligibility requirements, investment options, and the triple tax advantage that makes HSAs one of the most powerful savings tools available. Whether you are preparing for a professional benefits certification exam or simply want to sharpen your knowledge of employer-sponsored health savings accounts, a comprehensive PDF study guide lets you prepare at your own pace—offline, on paper, or on any device.
This free downloadable PDF contains practice test questions and answers covering every major HSA topic tested on certification and benefits exams, including IRS rules, HDHP thresholds, rollover rules, Medicare coordination, and qualified medical expense categories.
To open and contribute to an HSA, you must meet several IRS requirements. You must be enrolled in a qualifying High-Deductible Health Plan (HDHP). You cannot be enrolled in Medicare, cannot be claimed as a dependent on someone else's tax return, and cannot have any other non-HDHP health coverage (with limited exceptions for dental, vision, disability, and specific other insurance types).
Eligibility is determined on a month-by-month basis. If you become eligible mid-year and elect the "last-month rule," you can contribute the full annual amount—but you must remain HSA-eligible through the end of the following year to avoid taxes and penalties on the extra contribution.
The IRS sets minimum deductible and maximum out-of-pocket limits for HDHPs annually. For 2025, a qualifying HDHP must have a minimum deductible of $1,650 for self-only coverage or $3,300 for family coverage. Maximum out-of-pocket limits for 2025 are $8,300 (self-only) and $16,600 (family). These thresholds are adjusted each year for inflation, making it critical for HR professionals to verify current IRS figures each plan year.
The IRS sets annual contribution limits that cover all contributions to your HSA—including your own contributions and employer contributions combined. For 2025, the limit is $4,300 for self-only HDHP coverage and $8,550 for family coverage. Account holders who are age 55 or older (but not yet enrolled in Medicare) can make an additional $1,000 catch-up contribution each year.
Contributions can be made by the account holder, their employer, a family member, or any other person on behalf of the account holder. However, the combined total from all sources cannot exceed the IRS limit. Excess contributions are subject to a 6% excise tax.
Employers may contribute to employees' HSAs, and these contributions are excluded from the employee's gross income and are not subject to FICA taxes. Employers are not required to contribute equally to all employees' HSAs, but contributions must comply with comparability rules (for non-cafeteria plan contributions) or non-discrimination rules (for contributions made through a Section 125 cafeteria plan). Employer contributions count toward the annual IRS limit.
HSAs offer a uniquely powerful triple tax benefit unmatched by any other savings vehicle:
1. Pre-tax contributions: Contributions made through payroll deduction reduce your taxable income. Contributions made directly (outside payroll) are deductible on your federal tax return, even if you do not itemize.
2. Tax-free growth: Interest, dividends, and investment gains accumulate inside the HSA free of federal income tax. Many states also follow federal tax treatment, though a handful of states—notably California and New Jersey—do not recognize HSA tax advantages.
3. Tax-free withdrawals: Distributions used for qualified medical expenses are completely tax-free at the federal level. This means no income tax and no penalty when you pay for eligible healthcare costs with HSA funds.
Qualified medical expenses are defined by IRS Publication 502. The list includes most healthcare costs not covered by insurance: deductibles, copayments, coinsurance, prescription drugs, insulin, dental care (fillings, extractions, orthodontia), vision care (exams, glasses, contact lenses, LASIK), mental health services, chiropractic treatment, hearing aids, and long-term care insurance premiums (up to IRS limits). Over-the-counter medications and menstrual care products became permanently qualified after the CARES Act of 2020. Cosmetic surgery and most gym memberships are not qualified expenses.
Many HSA custodians allow account holders to invest HSA balances beyond a minimum cash threshold (commonly $1,000–$2,000) in mutual funds, ETFs, stocks, or bonds. Invested funds grow tax-free. This investment feature transforms the HSA from a simple spending account into a long-term retirement and healthcare savings vehicle. Financial advisors frequently recommend maximizing HSA contributions, paying medical expenses out-of-pocket when possible, and letting the HSA balance grow invested for decades.
Understanding how HSAs compare to other account-based health plans is a common exam topic. A Flexible Spending Account (FSA) is employer-owned, subject to a "use it or lose it" rule (with a limited grace period or $640 rollover option in 2024), does not require HDHP enrollment, and cannot be invested. A Health Reimbursement Arrangement (HRA) is funded exclusively by the employer, is employer-owned, is not portable when you leave employment, and reimburses employees for qualified expenses. The HSA is the only account that is employee-owned, fully portable, rolls over with no limit, and offers investment options.
Unlike FSAs, HSA funds never expire. Your entire balance rolls over from year to year regardless of whether you spend it or not. There is no deadline to use HSA funds, no annual forfeiture, and no limit on how large your HSA balance can grow. This makes the HSA especially powerful as a long-term savings tool for healthcare costs in retirement, when medical expenses typically increase significantly.
Once you enroll in any part of Medicare (Part A, Part B, Part C, or Part D), you can no longer contribute to an HSA. However, you can continue to use your existing HSA balance tax-free for qualified medical expenses, including Medicare premiums (Parts B, C, and D), Medicare deductibles, copays, and coinsurance. Medigap (Medicare Supplement) premiums are not qualified HSA expenses.
If you delay Medicare enrollment past age 65 (e.g., because you are still working with employer coverage), you must stop HSA contributions six months before you apply for Medicare or Social Security benefits, because Medicare Part A retroactively covers up to six months prior to the application date.
At age 65, HSA rules become more flexible. You can withdraw HSA funds for any reason—not just qualified medical expenses—without the 20% penalty that applies before age 65. Non-medical withdrawals after 65 are simply subject to ordinary income tax, making the HSA function similarly to a traditional IRA for non-medical expenses. For qualified medical expenses, withdrawals remain completely tax-free at any age.
HSAs are generally not subject to ERISA when the employer limits its involvement to making contributions and does not control or administer the accounts. However, if an employer bundles HSA benefits with other benefits or exercises too much control, ERISA obligations may apply. Benefits administrators must understand the "safe harbor" conditions that keep employer HSA programs outside ERISA's requirements, including allowing employees to choose their own HSA custodian and not limiting investment options.
Print the PDF or save it to your device for flexible, offline study. Work through each question independently before checking the answer explanations, which reference the relevant IRS rules and regulatory sources. Focus extra time on topics where you miss questions—contribution limits, HDHP thresholds, and Medicare coordination are frequently tested areas.
For additional practice, including timed quizzes and scored practice tests, visit our full HSA practice tests page where you can test your knowledge interactively across all HSA certification topics.