Social Security Tax Explained (2025)

Social Security tax is the larger half of FICA. It’s a 6.2% payroll tax taken from your wages that funds retirement, disability and survivor benefits for millions of Americans. Unlike Medicare, it has a hard ceiling.

The 6.2% rate and the wage base

You pay 6.2% on your earnings up to an annual wage base of $176,100 (2025). Earn more than that and the extra isn’t taxed for Social Security — so the most any single worker pays in 2025 is about $10,918. The cap rises most years with average wages.

What it funds

• Retirement benefits — based on your highest 35 years of earnings.
• Disability insurance — if you can no longer work.
• Survivor benefits — for your spouse and dependents.

Self-employed? You pay both halves

If you work for yourself, there’s no employer to split the bill, so you pay the full 12.4% Social Security portion as part of self-employment tax — see our self-employed taxes guide.

Does a 401(k) reduce it?

No. Like all of FICA, Social Security tax applies to your gross wages — traditional 401(k) contributions lower your income tax but not this. See how a 401(k) affects your take-home pay.

See your contribution

The calculator shows Social Security as its own line for any salary, so you can see exactly how much you contribute — and where you hit the wage-base cap.