The Social Security line on your pay stub is a federal payroll tax equal to 6.2% of your gross wages, withheld automatically every pay period to fund the Old-Age, Survivors, and Disability Insurance (OASDI) program. In 2026, it applies to the first $184,500 you earn. Your employer pays a matching 6.2% that never touches your paycheck, so the total sent to the federal trust funds on your wages is 12.4%.1Office of the Law Revision Counsel. 26 USC 3101 – Rate of Tax
The deduction is authorized by the Federal Insurance Contributions Act (FICA), which is why some pay stubs label it “FICA-OASDI” or lump it under a “FICA” heading. There is no opt-out form and no way to defer it. The money goes into a shared trust fund that pays current beneficiaries, not into a personal account with your name on it.
How the 6.2% Is Calculated on Your Paycheck
The rate is a flat 6.2% of gross wages for the pay period. Payroll multiplies your gross by 0.062 and withholds the result. On a $1,000 paycheck, that is $62. On a $5,000 biweekly check, it is $310. The math is linear all the way up to the annual wage cap.
The 6.2% rate is set by statute and has been unchanged since 1990. Unlike the wage cap, it does not adjust each year with inflation. Congress would have to pass a new law to move it.
What Counts as Wages for This Tax
The statute defines wages as “all remuneration for employment,” which covers base pay, hourly earnings, overtime, bonuses, and commissions.2Office of the Law Revision Counsel. 26 US Code 3121 – Definitions Two common pre-tax deductions behave differently, and the difference shows up on your stub:
- Traditional 401(k) contributions reduce your federal income tax but are still subject to Social Security tax. Your Social Security wages will be higher than your federal taxable wages by the amount you deferred.3Internal Revenue Service. Are Retirement Plan Contributions Subject to Withholding for FICA, Medicare, or Federal Income Tax
- Section 125 cafeteria plan deductions for qualifying health insurance, dental, or flexible spending accounts are excluded from Social Security wages. These reduce both your income tax and the 6.2% withholding.4Internal Revenue Service. FAQs for Government Entities Regarding Cafeteria Plans
The difference matters over a career. Section 125 deductions lower the wage figure Social Security uses when it later calculates your benefit. 401(k) contributions do not.
The 2026 Wage Base Limit
Social Security tax only applies up to a set annual amount of earnings. For 2026, that cap is $184,500. Once your year-to-date wages cross it, your employer stops withholding the 6.2% for the rest of the calendar year. The maximum an employee can pay in Social Security tax for 2026 is $11,439, which is $184,500 multiplied by 6.2%.5Social Security Administration. Contribution and Benefit Base
High earners often notice their take-home pay rise in late fall or early winter when they clear the ceiling. The cap moves each year with the national average wage index. It was $176,100 in 2025 and $168,600 in 2024.6Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet
If You Changed Jobs During the Year
Each employer tracks the wage cap from zero. A new employer has no way to know what a previous one already withheld, so combined withholding across two jobs can exceed $11,439. You recover the excess as a credit on Form 1040 when you file your annual return, using the W-2 from each employer to calculate the overpayment.7Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld
If a single employer withheld too much through a payroll error, the 1040 credit does not apply. You have to ask that employer to correct the mistake and refund the excess directly.7Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld
The Employer Pays a Matching 6.2%
Under 26 U.S.C. ยง 3111, your employer owes a matching 6.2% on the same wages you were taxed on.8Office of the Law Revision Counsel. 26 USC 3111 – Rate of Tax That share does not appear on your pay stub and does not reduce your paycheck, but it is a real cost of employing you. The employee 6.2% plus the employer 6.2% is the 12.4% that funds Social Security benefits.
Social Security vs. Medicare on the Same Stub
Most pay stubs show Social Security and Medicare as two separate lines even though both fall under FICA. They work differently:
- Social Security (OASDI): 6.2% of wages up to $184,500. Withholding stops once you hit the cap.
- Medicare (HI): 1.45% of every dollar of wages, with no cap.6Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet
- Additional Medicare Tax: an extra 0.9% on wages above $200,000 in a calendar year ($250,000 for married filing jointly), withheld by the employer once you cross $200,000. The employer does not match this 0.9%.1Office of the Law Revision Counsel. 26 USC 3101 – Rate of Tax
So the combined employee FICA rate is 7.65% on wages up to $184,500. From $184,500 to $200,000, only the 1.45% Medicare portion continues. Above $200,000, the Medicare portion rises to 2.35%.
Who Is Exempt
Most workers cannot avoid the 6.2% withholding. A few narrow categories are legally exempt:
- Students enrolled at least half-time who work for the same college or university they attend, where the work is incidental to their studies and they do not receive benefits that would make them a professional employee of the school.9Internal Revenue Service. Student FICA Exception
- Nonresident alien students on F-1, J-1, or M-1 visas who have been in the United States for fewer than five calendar years, for qualifying employment such as on-campus work or authorized practical training.10Internal Revenue Service. Foreign Student Liability for Social Security and Medicare Taxes
- Members of a recognized religious group that has existed continuously since December 31, 1950, and is conscientiously opposed to accepting Social Security benefits. Both the individual and the group must waive all rights to Social Security and Medicare benefits, using IRS Form 4029.
- Some state and local government employees covered by a qualifying public retirement system and not covered under a Section 218 agreement between their state and the Social Security Administration.
There is no general exemption based on age, income level, or personal preference.
What the Withholding Earns You
The 6.2% is not only a tax. It builds credits toward a future benefit. In 2026, you earn one Social Security credit for every $1,890 in covered wages, up to four credits per year, which means earning at least $7,560 in the year gives you the maximum four.11Social Security Administration. How Do I Earn Social Security Credits and How Many Do I Need to Be Eligible for Benefits
Retirement benefits require 40 credits, roughly ten years of covered work. Disability and survivor benefits have lower thresholds that vary by age. Your monthly benefit is calculated from your 35 highest-earning years, so the wages the 6.2% is withheld from directly shape the check you eventually receive. Years with no covered earnings still count in that 35-year average as zeros, which pulls the benefit down.
You can check your credit count and see an estimate of your future benefit by creating an account at ssa.gov. Reviewing it against your pay stubs and W-2s once a year is the simplest way to catch a payroll error before it reaches your retirement calculation.