What FICA taxes are and why you calculate them

FICA stands for Federal Insurance Contributions Act. It is the payroll tax that funds Social Security and Medicare. You calculate FICA taxes to understand how much of your paycheck goes toward these programs, to verify your employer withheld the correct amount, or to figure out what you owe if you are self-employed.

FICA has two parts: Social Security tax and Medicare tax. Each part has its own rate and its own rules about what income counts. The calculation changes depending on whether you are an employee or self-employed, and it changes each year because the Social Security wage base — the maximum income subject to Social Security tax — increases annually.

Most employees never calculate FICA themselves because their employer withholds it automatically. But understanding the math helps you read your pay stub, catch errors, or plan for self-employment taxes.

Key Takeaways

  • Employee Social Security tax is 6.2 percent of wages up to an annual cap (which changes yearly), and Medicare tax is 1.45 percent of all wages with no cap.
  • Self-employed people pay both the employee and employer portions of FICA, totaling 15.3 percent, but can deduct half of the self-employment tax on their income tax return.
  • Additional Medicare tax of 0.9 percent applies to wages above $200,000 for single filers and $250,000 for married filing jointly, with no employer match.
  • To calculate FICA, multiply your gross wages by the tax rate for each component, then add them together.
  • Your W-2 form shows total FICA withheld, and Schedule SE (for self-employed) calculates self-employment tax using net profit from Schedule C.

Employee FICA calculation: Social Security and Medicare

If you are an employee, your employer withholds FICA from your paycheck. To calculate what should be withheld, start with your gross wages — the amount before any deductions.

For Social Security tax, multiply your gross wages by 6.2 percent, but only up to the annual wage base. In 2024, the wage base is $168,600. This means if you earn $168,600 or more in a year, you pay 6.2 percent only on the first $168,600. Once you hit that cap, no more Social Security tax is withheld for the rest of the year. The wage base changes each year; the Social Security Administration publishes the new figure in October for the following year.

For Medicare tax, multiply your gross wages by 1.45 percent. There is no wage cap for Medicare — you pay 1.45 percent on every dollar you earn, no matter how much you make.

Add the two amounts together to get your total FICA withholding for that pay period. Your pay stub should show both amounts separately.

Additional Medicare tax for higher earners

If your wages exceed certain thresholds, you owe an additional Medicare tax of 0.9 percent. The thresholds are $200,000 for single filers, $250,000 for married filing jointly, and $125,000 for married filing separately.

This threshold is based on your filing status and applies to the total wages you receive in a calendar year, not per paycheck. Your employer withholds the additional 0.9 percent once your year-to-date wages cross the threshold. Unlike regular Medicare tax, there is no employer match — you pay the full 0.9 percent yourself.

If you have multiple jobs or your spouse also works, the withholding can get complicated because each employer withholds based only on what they pay you. You may end up overpaying and need to claim a refund on your tax return, or you may underpay and owe when you file. The IRS Form 8959 helps you sort this out.

Self-employment FICA calculation using Schedule SE

If you are self-employed, you pay both the employee and employer portions of FICA, called self-employment tax. The total rate is 15.3 percent: 12.4 percent for Social Security and 2.9 percent for Medicare.

You calculate self-employment tax on Schedule SE, which is part of your federal income tax return. Start with your net profit from Schedule C (Profit or Loss from Business). Net profit is your business income minus business expenses.

On Schedule SE, you multiply your net profit by 92.35 percent. This adjustment accounts for the fact that self-employed people can deduct half of their self-employment tax as a business expense. Then multiply that result by 15.3 percent to get your self-employment tax.

The Social Security portion still has a wage base cap. In 2024, you pay 12.4 percent Social Security tax only on the first $168,600 of net profit. Medicare tax of 2.9 percent applies to all net profit. If your net profit exceeds $200,000 (or $250,000 if married filing jointly), you also owe the additional 0.9 percent Medicare tax on the excess.

How to read your W-2 and verify FICA withholding

Your employer sends you a W-2 form by January 31 each year. Box 2 shows federal income tax withheld. Boxes 4 and 6 show Social Security and Medicare tax withheld.

To verify the amounts are correct, take the wages in Box 1 (or Box 5 for Medicare wages, which may be higher if you received certain fringe benefits). Multiply by 6.2 percent up to the annual wage base for Social Security. Multiply all wages by 1.45 percent for Medicare. The results should match boxes 4 and 6.

If you earned over $200,000 (single) or $250,000 (married filing jointly), check that your employer withheld the additional 0.9 percent Medicare tax. This appears in Box 6 as part of total Medicare tax withheld. If you had multiple jobs and each employer withheld the additional tax, you may have overpaid; you can claim the overpayment as a refund on your tax return using Form 8959.

FICA calculation example for an employee

Suppose you earn $5,000 gross per paycheck, paid biweekly. Your Social Security tax is $5,000 × 6.2% = $310. Your Medicare tax is $5,000 × 1.45% = $72.50. Your total FICA withholding is $382.50 per paycheck.

Now suppose it is late in the year and your year-to-date wages have already reached $168,600. On your next paycheck, you owe no Social Security tax because you have hit the wage base cap. You still owe Medicare tax: $5,000 × 1.45% = $72.50. If your wages exceed $200,000 for the year, you also owe the additional Medicare tax: $5,000 × 0.9% = $45. Your total FICA withholding for that paycheck is $72.50 + $45 = $117.50.

FICA calculation example for self-employed

Suppose you are a freelancer with $80,000 in net profit for the year. On Schedule SE, you multiply $80,000 by 92.35% = $73,880. Then multiply by 15.3% = $11,304.24. This is your self-employment tax.

Of this, $73,880 × 12.4% = $9,161.12 is Social Security tax, and $73,880 × 2.9% = $2,142.52 is Medicare tax. You report this on Schedule SE and transfer it to your Form 1040. You can deduct half of the self-employment tax ($5,652.12) as an adjustment to income on your return.

Frequently Asked Questions

Why does my Social Security tax stop partway through the year?

Social Security tax has an annual wage base cap, which is $168,600 in 2024. Once your year-to-date wages reach that amount, no more Social Security tax is withheld for the rest of the year. Medicare tax has no cap and continues all year. The wage base increases most years to account for inflation.

Do I pay FICA on tips?

Yes. Tips are considered wages for FICA purposes. Your employer should include reported tips in your gross wages on your pay stub and W-2. If you receive cash tips you did not report to your employer, you still owe FICA tax on them when you file your tax return.

What if I had two jobs and both employers withheld additional Medicare tax?

Each employer withholds the additional 0.9 percent Medicare tax once your wages at that job exceed the threshold, but the threshold is based on total wages across all jobs. You may overpay. File Form 8959 with your tax return to calculate the correct amount and claim a refund for the overpayment.

Can I reduce my FICA taxes?

Employees cannot reduce FICA taxes through deductions or credits. The rate and wage base are set by law. Self-employed people can deduct half of their self-employment tax as an adjustment to income, which lowers their overall tax bill but not the FICA tax itself.

Where do I report self-employment FICA taxes on my return?

Calculate self-employment tax on Schedule SE and attach it to your Form 1040. The total self-employment tax transfers to your Form 1040, and half of it is deducted as an adjustment to income. Self-employment tax is separate from income tax and is always owed, even if you have no income tax liability.