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ARTICLE 3
Why an FSA?
2026 Contribution Limit
You can contribute up to
$3,400
to a health FSA in 2026.
View plan rules
What is a Health FSA?
The Potential Tax Advantage
Your Decision Matters
When Your Money is Available
The Tradeoff: Unused Funds Matter
Key FSA Terms
Before You Make a Decision
Official Resources
Choosing Your Contribution
Updated for the 2026 plan year
How Much Should You Put in Your FSA?
Learn how to estimate the year ahead and make a more informed contribution decision.
Choosing an FSA contribution presents an unusual problem.
You generally make the decision before the year unfolds.
Some expenses are nearly certain. Others are probable. Some are possible. And some healthcare expenses will arise that you could not reasonably predict at all.
That is why simply looking at last year's spending—or choosing the federal maximum—isn't necessarily a good contribution strategy.
Start with what you know
Begin with healthcare expenses that you have a strong reason to expect.
Examples might include:
Recurring expenses
Regular prescriptions, recurring treatment, established therapy, predictable supplies, or other ongoing eligible costs.
Scheduled care
Known dental work, planned procedures, vision appointments, or other care already expected during the applicable period.
Expected family expenses
Qualifying expenses for a spouse, children, or other eligible family members.
These expenses create the strongest foundation for an estimate.
Then consider what you reasonably expect
Some expenses aren't certain but have a meaningful likelihood of occurring.
Perhaps a dentist has told you that a procedure will probably be needed. Maybe a prescription could continue but may change. Perhaps you expect new glasses but haven't chosen them yet.
Those expenses should not necessarily be treated as either $0 or 100% certain.
Their likelihood matters.
Separate possibilities from plans
One of the easiest ways to overfund an FSA is to turn every conceivable healthcare expense into an assumed expense.
There is a difference between:
“I have a dental procedure scheduled for March.”
and:
“At some point I might need dental work.”
Both may deserve consideration. They should not necessarily receive the same weight.
Look at what changed
Last year's spending can be informative, but it isn't automatically a forecast of this year.
Ask:
What is likely to repeat?
What happened last year that probably won't happen again?
What is new this year?
A completed procedure should not automatically be projected forward. A new recurring prescription probably should not be ignored simply because it wasn't part of last year's spending.
The useful information is not merely what you spent.
It is what changed.
Account for your plan rules
Your contribution decision also depends on what happens if your estimate is wrong.
If your plan permits a carryover, some unused funds may remain available in the following plan year. If it instead provides a grace period, qualifying expenses incurred during that additional period may use eligible remaining funds. If neither applies, unused funds may be forfeited under the plan's terms.
For 2026, the federal employee salary-reduction limit is $3,400, and the maximum permitted carryover for plans that offer a carryover is $680. Your own plan may permit a lower carryover or impose other applicable rules.
Don't optimize only for tax savings
Increasing your contribution can increase potential tax savings—but only while the money can ultimately be used for qualifying expenses.
That creates competing considerations:
Contribute too little: you may pay predictable eligible healthcare expenses with after-tax dollars after exhausting your FSA.
Contribute too much: you may have funds remaining that cannot be used or carried over under your plan.
The best decision is therefore not necessarily the highest contribution.
It is a contribution appropriate to your circumstances and the uncertainty surrounding them.
Think in ranges, not false precision
Healthcare spending is rarely predictable to the dollar.
A useful decision process should distinguish between:
a reasonable range;
the amount within that range most supported by what you currently know;
the expenses having the greatest effect on that result;
the uncertainty that remains.
That is why Calcumetic presents an FSA contribution estimate, rather than pretending to know exactly what you will spend.
Revisit the decision when circumstances change
Your underlying estimate can change even if your formal FSA election cannot.
A procedure may be canceled. A prescription may change. New care may become likely.
Where your plan and applicable law permit an election change, your plan administrator determines whether and how that change can be made. IRS guidance states that an election generally may be changed or revoked only where permitted by law and the plan.
Calcumetic can help you recalculate the estimate as your circumstances change, but it does not determine whether your employer will permit a corresponding election change.
That distinction is important.
Set aside pre-tax dollars
Pay for eligible healthcare expenses
Lower your taxable income
Get reimbursed tax-free for qualifying expenses
Did you know?
For 2026, plans that allow a carryover can let you carry over up to $680 of unused funds into the next plan year.
Next up
The FSA Rules That Can Change Your Decision
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Understand how an FSA works, its tax advantages, and what to know before choosing your contribution
