HSA vs FSA Reimbursement Calculator

Calculator Inputs

Large screens show three columns, medium screens show two, and mobile shows one.

Medical expenses

Dental and vision expenses

Other eligible expenses

Employee HSA contribution

Employee FSA election

Employer HSA contribution

Employer FSA contribution

Federal tax rate (%)

State tax rate (%)

FICA tax rate (%)

FSA rollover limit

HSA reimbursement now (%)

HSA growth rate (%)

Planning horizon (years)

Reset

Formula Used

Total Eligible Expenses
Medical Expenses + Dental/Vision Expenses + Other Eligible Expenses

Combined Tax Rate
Federal Tax Rate + State Tax Rate + FICA Tax Rate

HSA Tax Savings
Employee HSA Contribution × Combined Tax Rate

FSA Tax Savings
Employee FSA Election × Combined Tax Rate

HSA Reimbursed Now
min(Total Eligible Expenses × HSA Reimbursement Now %, HSA Available Funds)

HSA Future Value
HSA Left Invested × (1 + Growth Rate)^Years

FSA Reimbursement
min(Total Eligible Expenses, FSA Available Funds)

FSA Rollover Kept
min(Unused FSA Balance, FSA Rollover Limit)

Estimated HSA Total Value
HSA Reimbursed Now + HSA Tax Savings + HSA Future Value

Estimated FSA Total Value
FSA Reimbursement + FSA Tax Savings + FSA Rollover Kept − FSA Forfeited

This calculator compares modeled value, reimbursement timing, and unused balance risk under your assumptions. It is a planning tool, not legal or tax advice.

How to Use This Calculator

Enter expected annual eligible healthcare expenses across medical, dental/vision, and other qualified categories.
Add your planned employee contributions and any employer contributions for each account type.
Enter federal, state, and FICA tax rates to estimate payroll tax savings from pre-tax elections.
Set the FSA rollover limit your plan allows.
Choose how much of your HSA spending you want reimbursed now.
Add an HSA growth rate and planning horizon to model long-term retained value.
Click Compare HSA vs FSA to display the result under the header and above the form.
Review the chart, step breakdown, and download the result as CSV or PDF.

Example Data Table

Scenario	Eligible Expenses	Employee HSA	Employee FSA	Employer HSA	Combined Tax Rate	FSA Rollover	HSA Growth	Planning Years
Balanced medical year	$4,000	$3,200	$3,200	$600	34.65%	$640	6%	10
Low-usage year	$1,800	$3,000	$3,000	$500	30.00%	$640	5%	12
High-expense year	$6,500	$4,000	$4,000	$800	37.00%	$640	7%	15

FAQs

1. What does this calculator compare?

It compares estimated reimbursement value, payroll tax savings, rollover protection, possible forfeiture, and long-term retained value under your own assumptions.

2. Why can the HSA look stronger over time?

An HSA may preserve unused funds and potentially grow over multiple years. This calculator models that using your selected growth rate and planning horizon.

3. Why can an FSA still win in some cases?

If you expect to spend most funds during the plan year, the immediate reimbursement plus tax savings can be very efficient, especially when forfeiture risk is low.

4. What is the reimbursement now percentage for HSA?

It estimates how much of your eligible expenses you choose to reimburse immediately from the HSA instead of leaving money in the account for future use.

5. Does the calculator include employer contributions?

Yes. Employer contributions are added to available funds for each account, helping you see total reimbursable value and leftover balances more clearly.

6. What happens to unused FSA money here?

The calculator first applies your rollover limit. Any remaining unused balance above that limit is treated as forfeited in the comparison.

7. Can I use this for actual enrollment decisions?

Use it as a planning aid. Actual eligibility, contribution limits, rollover rules, and reimbursements depend on your employer plan and current regulations.

8. Can someone have both an HSA and FSA?

Some arrangements may allow limited combinations, but plan design matters. This page focuses on comparing modeled reimbursement outcomes, not confirming eligibility rules.