FICA is calculated as a percentage of your gross wages, taken from each paycheck

FICA stands for Federal Insurance Contributions Act, and it funds Social Security and Medicare. Your employer calculates FICA by taking a set percentage of your pay before taxes are withheld. For 2024, the rate is 6.2% for Social Security and 1.45% for Medicare — your employer matches these amounts, so you see them deducted from your paycheck while your employer pays an equal share to the government.

The calculation happens automatically on most paychecks, but understanding how it works helps you read your pay stub and plan your taxes. The math is straightforward: multiply your gross wages by the FICA percentage, and that is what comes out of your check.

If you are self-employed, you calculate FICA differently — you pay both the employee and employer share, which is 15.3% total. W-2 employees never need to do this math themselves, but knowing the formula helps you verify your pay stub is correct.

Key Takeaways

  • FICA is 7.65% of your gross pay for most W-2 employees: 6.2% for Social Security and 1.45% for Medicare.
  • Your employer deducts FICA from your paycheck and also pays an equal amount to the government on your behalf.
  • Social Security tax stops once you reach the annual wage cap, which was $168,600 in 2024, but Medicare tax continues on all wages.
  • Self-employed workers pay 15.3% total FICA because they cover both the employee and employer portions.
  • You can verify FICA amounts on your pay stub by multiplying your gross pay by 0.062 for Social Security and 0.0145 for Medicare.

The basic FICA calculation for W-2 employees

Start with your gross pay — the amount before any deductions. This is the number at the top of your pay stub, before federal income tax, state tax, or health insurance premiums are subtracted.

Multiply gross pay by 0.062 to find your Social Security tax. For example, if you earn $2,000 in a paycheck, your Social Security tax is $2,000 × 0.062 = $124.

Multiply gross pay by 0.0145 to find your Medicare tax. Using the same $2,000 paycheck, your Medicare tax is $2,000 × 0.0145 = $29. Your total FICA for that check is $124 + $29 = $153.

This calculation repeats on every paycheck throughout the year. Your employer's payroll system does it automatically, but the formula stays the same each time.

Why the Social Security wage cap matters

Social Security tax only applies to wages up to an annual limit. In 2024, that limit is $168,600. Once you earn that much in a calendar year, your employer stops deducting Social Security tax from your remaining paychecks for that year.

Medicare tax has no wage cap — it continues on every dollar you earn, no matter how high your annual income goes. This is why high earners see Social Security tax disappear partway through the year but Medicare tax on every check.

If you change jobs mid-year, each employer calculates Social Security tax independently based on what they pay you. You could end up paying Social Security tax on more than $168,600 if you worked for multiple employers. When you file your tax return, you can claim a refund for the overpayment.

How self-employed FICA works differently

Self-employed workers pay self-employment tax, which is FICA's equivalent for people without an employer. The rate is 15.3% — 12.4% for Social Security and 2.9% for Medicare — because you cover both the employee and employer portions.

You calculate self-employment tax on your net profit from Schedule C (your business income minus business expenses), not your gross revenue. If your net profit is $50,000, your self-employment tax is roughly $50,000 × 0.153 = $7,650.

Self-employed workers report self-employment tax on Schedule SE and pay it through quarterly estimated tax payments or when they file their annual return. The Social Security wage cap still applies — once your net profit reaches $168,600, you stop paying the 12.4% Social Security portion on additional income, though the 2.9% Medicare portion continues.

Reading FICA on your pay stub

Your pay stub breaks down FICA into two line items: one labeled "Social Security" or "OASDI" (Old-Age, Survivors, and Disability Insurance) and one labeled "Medicare" or "HI" (Hospital Insurance). The amounts should match the calculation above.

Check that your gross pay is correct — this is the starting number for all FICA calculations. Then verify that Social Security tax is roughly 6.2% of gross and Medicare tax is roughly 1.45% of gross. If the numbers are significantly off, contact your payroll department.

Your pay stub also shows your employer's FICA contribution, though this does not come out of your check. This line is informational and shows the total FICA cost to your employer.

What happens if you overpay FICA

Overpayment usually happens when you work for multiple employers in the same year. If your combined wages from all jobs exceed the Social Security wage cap, you will have paid Social Security tax on more than you should have.

You cannot get a refund directly from your employer. Instead, you claim the overpayment on your federal tax return using Form 1040. The IRS calculates how much you overpaid and refunds it when you file.

Medicare tax overpayment is rare but can happen if you earn over $200,000 as a single filer (or $250,000 if married filing jointly). An additional 0.9% Medicare tax applies to wages above these thresholds. Your employer should withhold this automatically, but verify it on your pay stub if your income is high.

Common mistakes when calculating FICA

The most common mistake is using net pay instead of gross pay. FICA is always calculated on gross wages before any deductions. If you subtract health insurance, 401(k) contributions, or other pre-tax deductions before calculating FICA, your number will be too low.

Another mistake is forgetting that the Social Security wage cap resets every January. If you worked for the same employer last year and paid Social Security tax all year, you still pay it again in January of the new year — the cap does not carry over.

Self-employed workers sometimes calculate self-employment tax on gross revenue instead of net profit. You must subtract business expenses first. Using gross revenue inflates your FICA by thousands of dollars.

Frequently Asked Questions

Can I reduce my FICA taxes?

No. FICA rates are set by law and explore to nearly all workers. You cannot lower the percentage or avoid paying it. The only exception is certain religious groups that have filed for exemption with the IRS, which is rare and requires specific conditions.

Why do I pay FICA if I will not collect Social Security?

FICA funds not only your own future benefits but also current retirees, disabled workers, and survivors of deceased workers. Even if you do not collect, your contributions support the program. Some workers do not collect because they die before retirement or move out of the country, but FICA is mandatory regardless.

What if my employer did not deduct FICA from my paycheck?

Contact your payroll department when ready. FICA is mandatory, and your employer is required to withhold it. If they did not, they are breaking the law, and you may owe the taxes when you file your return. Document the issue and report it to your state labor department if your employer refuses to correct it.

Do tips count toward FICA?

Yes. Tips are considered wages for FICA purposes. If you report tips to your employer, they withhold FICA on the tip amount. If you do not report tips, you still owe self-employment tax on them when you file your return.

How do I know if I have paid enough FICA for the year?

Check your year-to-date FICA amounts on your most recent pay stub. For Social Security, multiply your year-to-date gross wages by 0.062 — if you have not reached the wage cap, this is what you should have paid. For Medicare, multiply year-to-date gross by 0.0145. Your pay stub should show these amounts in the year-to-date column.