FICA Wage Base Explained: Social Security and Medicare Tax Limits

What Is FICA?

FICA stands for the Federal Insurance Contributions Act. It is a payroll tax split into two components: Social Security (officially called Old-Age, Survivors, and Disability Insurance, or OASDI) and Medicare (Hospital Insurance, or HI). Both the employee and employer pay equal shares, though the employee only sees their half on a paycheck.

2025 FICA Rates and Wage Base

Social Security: 6.2% on earnings up to $176,100 (the 2025 wage base). Your employer pays a matching 6.2%, bringing the total to 12.4%. Once your year-to-date earnings exceed $176,100, Social Security withholding stops for the rest of the year. This means high earners see slightly larger paychecks in the last few months of the year.

Medicare: 1.45% on all earnings with no cap. Your employer matches at 1.45%. Additionally, there is a 0.9% Additional Medicare Tax on individual earnings above $200,000 ($250,000 for married filing jointly). The employer does not match this surtax.

How the Wage Base Affects Your Paycheck

If you earn $176,100 or less annually, Social Security is withheld from every paycheck at a consistent 6.2%. If you earn more, the math changes mid-year. For example, someone earning $220,000 annually on a biweekly schedule hits the $176,100 cap around paycheck 21 (late October). From that point forward, Social Security withholding drops to $0, and net paychecks increase by roughly $524 each.

This is why some high earners notice a "bonus" feeling in their late-year paychecks — it is not a bonus, it is just the Social Security cap being reached.

How the Wage Base Has Changed Over Time

The Social Security wage base increases most years, tied to the national average wage index. In 2020, it was $137,700. By 2023 it reached $160,200, and in 2024 it jumped to $168,600. The 2025 figure of $176,100 represents a significant increase that affects more workers each year as wages rise. This gradual expansion means more of your income is subject to Social Security tax over time.

Self-Employment and FICA

Self-employed individuals pay both the employee and employer portions, totaling 15.3% (12.4% Social Security + 2.9% Medicare) on net self-employment income. However, you can deduct the employer-equivalent half (7.65%) from your adjusted gross income on your tax return. The same $176,100 wage base and $200,000 Additional Medicare Tax threshold apply.

Why This Matters for Job Comparisons

When comparing job offers, FICA is a fixed cost that does not change between employers (unlike benefits or retirement matches). But the wage base matters: a job paying $180,000 versus $170,000 means slightly different FICA math since the higher salary exceeds the cap. Use our paycheck calculator to see the exact impact on your take-home pay, or browse salary data by job title to understand typical ranges.