Federal Insurance Contributions Act — the Social Security and Medicare tax on your paycheck.
Common paystub code: FICA
FICA stands for the Federal Insurance Contributions Act, a U.S. law that mandates a payroll tax on both employees and employers to fund Social Security and Medicare. In 2026, employees pay 6.2% for Social Security (up to a wage base of $168,600) and 1.45% for Medicare (no cap), for a total FICA rate of 7.65%. Your employer matches this amount, meaning the total FICA contribution is 15.3%.
FICA appears as one or two separate lines on most paystubs — typically labeled "FICA," "OASDI" (Social Security), and "MED" or "MEDEE" (Medicare). Together they form the foundation of America's federal social-insurance programs, which pay benefits to over 70 million retirees, survivors, and disabled workers each month.
How FICA is calculated. FICA is computed on your gross wages, not your net pay. For a worker earning $5,000 in a pay period, FICA withholding is 6.2% × $5,000 = $310 (Social Security) plus 1.45% × $5,000 = $72.50 (Medicare), for a total FICA deduction of $382.50. Your employer matches this exact amount and remits the combined $765 to the IRS.
The wage-base cap matters. Once your year-to-date wages exceed $168,600 (the 2026 Social Security wage base), the 6.2% Social Security portion stops being withheld for the rest of the year. The Medicare portion, however, has no cap — high earners continue paying 1.45% on every dollar, plus an additional 0.9% surtax on wages above $200,000 (single filer). This is why many high earners notice slightly bigger paychecks toward year-end.
Self-employed workers pay both halves. If you're a 1099 contractor or sole proprietor, you owe the full 15.3% (both employee and employer portions) as Self-Employment Tax (SECA), reported on Schedule SE of your annual Form 1040. You do get to deduct half of it as an above-the-line deduction.
Common mistake: Some workers think FICA contributions are like a savings account they'll get back at retirement. They're not — FICA funds CURRENT retirees and your eventual benefits depend on a separate formula based on your 35 highest-earning years.
Source: IRS Publication 15 (Circular E) and Social Security Administration FICA wage base announcements.