FICA Tax Calculator (Social Security + Medicare)

FICA = Federal Insurance Contributions Act. It funds Social Security (Old-Age, Survivors, Disability Insurance) and Medicare (Hospital Insurance). Two components, two different bases:

Social Security: 6.2% employee + 6.2% employer = 12.4% total, capped at the annual wage base ($168,600 in 2024, indexed annually). Above that, no more Social Security tax.

Medicare: 1.45% employee + 1.45% employer = 2.9% total, no cap. Plus an Additional Medicare Tax of 0.9% paid only by employees on wages over $200,000 (single) or $250,000 (married filing jointly). Employer does NOT match the additional 0.9%.

Self-employed people pay both halves under the Self-Employment Contributions Act (SECA). Total SE tax = 15.3% on the first $168,600 (12.4% Social Security + 2.9% Medicare), then 2.9% Medicare on the rest, plus 0.9% Additional Medicare over the threshold. Half of SE tax is deductible on the front of Form 1040 (an above-the-line adjustment).

The Social Security wage base is the cap that matters most. It increases roughly 3-4% per year:

• 2024: $168,600
• 2023: $160,200
• 2022: $147,000
• 2021: $142,800
• 2020: $137,700

A high earner pays a hard $10,453 in employee Social Security tax in 2024 — period — regardless of whether they earn $170K or $1M.

The 0.9% Additional Medicare Tax wrinkle.

• Triggers at $200,000 of wages for single filers, $250,000 for MFJ.
• Employer withholds the 0.9% once wages exceed $200,000 from THAT employer.
• If a married couple files jointly and each earns $150K (combined $300K), each employer might not withhold (since each paycheck is below $200K), but the couple owes the additional tax on $50K. They reconcile on Form 8959 with the return.
• Employer never matches the 0.9%.

FICA on bonuses, equity, and tips.

• Bonuses: full FICA up to the cap.
• Equity (RSU/stock options on vesting/exercise): full FICA up to the cap. This often pushes high earners over the wage base on a single big vesting event.
• Tips: subject to FICA. Reported via Form 4070 by employee or Form 941 by employer.

Worked example — single filer, $250,000 W-2 wages.

• Social Security: 6.2% × $168,600 (capped) = $10,453.20
• Medicare base: 1.45% × $250,000 = $3,625
• Additional Medicare: 0.9% × ($250,000 - $200,000) = $450
• Total employee FICA = 10,453 + 3,625 + 450 = $14,528

Employer pays 6.2% × $168,600 + 1.45% × $250,000 = 10,453 + 3,625 = $14,078 (no additional 0.9%).

Combined cost to employer of paying this employee: $250,000 wages + $14,078 FICA = $264,078.

Worked example — self-employed, $100,000 net SE earnings.

• SE tax base = 92.35% of net earnings = $92,350 (the deduction for the SE tax half is built into the multiplier)
• SE Social Security: 12.4% × $92,350 = $11,451.40
• SE Medicare: 2.9% × $92,350 = $2,678.15
• Total SE tax = $14,129.55
• Half deductible = $7,064.78 reduces AGI

That is significantly more than a W-2 employee’s FICA on the same income, which is why SE taxpayers complain — they pay the employer share themselves.

Why FICA is regressive at the top. The 12.4% Social Security tax stops at $168,600. Earnings above that are not taxed for Social Security. So a $200K earner pays 6.2% × ($168,600/$200,000) = 5.2% effective rate; a $1M earner pays 1.05% effective rate. There are recurring proposals to raise or eliminate the wage base.