What's the difference between an HSA, FSA, and HRA?

All three are tax-advantaged accounts that pay healthcare expenses with pre-tax dollars, but they differ on ownership, eligibility, and rollover.

• HSA (Health Savings Account): employee-owned, requires enrollment in an HSA-qualified high-deductible health plan (HDHP), money rolls over year-to-year indefinitely, can be invested, portable when you change jobs, and triple-tax-advantaged (pre-tax contribution, tax-free growth, tax-free withdrawal for qualified medical). The most flexible of the three.
• FSA (Flexible Spending Account): employer-sponsored, no HDHP requirement, lower annual contribution cap, use-it-or-lose-it within the plan year (some plans allow a small carryover or grace period), not portable when you change jobs. Common as a payroll-deduction option for predictable medical spend.
• HRA (Health Reimbursement Arrangement): employer-funded only (employees don't contribute), reimburses qualified medical expenses up to a limit set by the employer, employer controls the rules (rollover, eligible expenses, what counts), not portable. Increasingly used in ICHRA form (Individual Coverage HRA) where employers fund employee purchase of individual marketplace plans.

For employees, HSA + HDHP is usually the most powerful combination if your medical spend is moderate and your cash flow can handle the high deductible. FSA is better for predictable, plannable spending. HRAs are entirely up to your employer's plan design.