HSA vs. FSA: how the two accounts actually differ

HSAs and FSAs are both tax-advantaged accounts for healthcare expenses, but they have fundamentally different rules, and which one is even available to you depends on the health plan you're enrolled in.

The core difference

An HSA (Health Savings Account) is tied to your health plan: you can only have one if you're enrolled in a high-deductible health plan (HDHP). The money is yours forever. It rolls over year to year, can be invested, and moves with you when you change jobs.

An FSA (Flexible Spending Account) is available with most employer health plans, including traditional PPOs and HMOs. The catch: it's use-it-or-lose-it. Unspent funds are forfeited at year-end (with a small employer-permitted rollover or grace period exception).

Contribution limits (2026)

HSA: $4,400 for self-only coverage, $8,750 for family coverage. If you're 55 or older and not enrolled in Medicare, add a $1,000 catch-up. Source: IRS Revenue Procedure 2025-19.

FSA: $3,400 per employee, with a carryover limit of $680 for plans that allow one. A married couple can each have their own FSA, since the limit is per employee, not per household. Source: IRS Revenue Procedure 2025-32.

These change every year. Confirm the current figures before you set an election.

Where the HSA is structurally different

For people enrolled in an HDHP, the HSA has properties no other account type has:

Triple tax advantage: Contributions are pre-tax (or tax-deductible). Growth is tax-free. Withdrawals for medical expenses are tax-free. No other account type has all three.

It's an investment account. Once you have a balance above the minimum (often $1,000–$2,000), you can invest in mutual funds. Many people treat HSA contributions like retirement contributions: contributing the max, paying medical bills out-of-pocket, and letting the HSA grow.

No deadline. Unlike an FSA, you can reimburse yourself for any medical expense you paid at any point in the past, as long as you have receipts. Some people pay bills out-of-pocket for years, then take one large tax-free reimbursement later.

Retirement utility. After age 65, HSA withdrawals for non-medical expenses are subject only to income tax, the same treatment as a traditional IRA.

Where the FSA applies

If you're not in an HDHP, the FSA is the tax-advantaged healthcare account available to you. Your plan documents state whether your plan qualifies as an HDHP.

Predictable expenses. If you know you'll spend $2,000 on orthodontics, therapy, or prescriptions, the FSA lets you pay for that with pre-tax dollars. What you save is your marginal tax rate applied to the amount you spend.

Dependent Care FSA. Even if you have an HSA, you can also have a Dependent Care FSA (for childcare and eldercare expenses, a separate account, up to $5,000). This is one of the most underused benefits available to working parents.

Limited Purpose FSA. If you have an HSA and want to also get FSA benefits, a Limited Purpose FSA (dental and vision expenses only) is HSA-compatible.

The enrollment window

Both HSAs and FSAs require enrollment decisions during open enrollment. You typically can't start mid-year unless you have a qualifying life event. The FSA requires an upfront annual election, so you commit to the full amount before the year starts.

Common mistakes to avoid

Not enrolling at all. Paying for healthcare with after-tax dollars when you could be using pre-tax money is leaving money on the table.

Over-contributing to an FSA. If you over-estimate your FSA usage, you forfeit the excess. Start conservatively if you're new to FSAs.

Under-contributing to an HSA. The HSA is one of the few accounts with three separate tax advantages, which is why some people max it and pay medical bills out of pocket instead, leaving the balance to grow.

Leaving an old HSA uninvested. An HSA balance sitting in a low-interest cash account is not growing tax-free. Most custodians allow investment once the balance clears a threshold, so it is worth checking what yours is.

LifQ keeps your HSA and FSA alongside your other financial protections, and reminds you before any deadline you add.

Your policy documents are the authority on what you have, and your carrier, plan administrator, or a licensed agent is the authority on what to change. LifQ's job is making sure you walk into that conversation knowing exactly what you already own.