The OASDI tax is the federal payroll tax that funds Social Security, and in 2026 it takes 6.2% of your wages up to $184,500. Your employer pays a matching 6.2%, for a combined 12.4% going into the system on your earnings.1Social Security Administration. Contribution and Benefit Base OASDI stands for Old-Age, Survivors, and Disability Insurance. Every dollar withheld under that label builds the earnings record the Social Security Administration uses to decide whether you qualify for benefits later, and how much you get.
What the Tax Buys You
OASDI funds three insurance programs, each tied to a different reason your paycheck might stop.
Retirement benefits are the largest piece. Once you accumulate 40 credits over your working life, you qualify for monthly payments when you retire.2Social Security Administration. Social Security Credits and Benefit Eligibility The amount depends on your highest-earning years, and someone retiring at full retirement age in 2026 can receive up to $4,152 a month.3Social Security Administration. What Is the Maximum Social Security Retirement Benefit Payable?
Survivors benefits go to the spouses, children, and dependent parents of workers who die. Disability benefits go to workers with a medical condition that prevents them from working for at least 12 consecutive months, under a strict definition that requires inability to do your prior work or adjust to other work.4Social Security Administration. Disability Benefits – How Does Someone Become Eligible?
These are earned benefits. Both eligibility and payment amounts are calculated from your lifetime earnings, which is why the deductions on your pay stub matter beyond the current year.
How Much You Actually Pay
The 6.2% employee rate and 6.2% employer match are set by statute and have not changed since 1990.5GovInfo. 26 USC 3101 – Rate of Tax The number that moves each year is the ceiling the rate applies to, called the Social Security wage base.
For 2026, that base is $184,500. Every dollar you earn above that is free of OASDI tax for the rest of the year. The most any single worker will pay in 2026 is $11,439, with the employer paying the same.1Social Security Administration. Contribution and Benefit Base
This cap is what makes OASDI different from the Medicare tax that sits next to it on your pay stub. Medicare’s 1.45% applies to every dollar you earn, with no ceiling. So a worker earning $300,000 will stop seeing OASDI withheld partway through the year while the Medicare line keeps running.1Social Security Administration. Contribution and Benefit Base
How It Shows Up on Your Paycheck
If You Receive a W-2
You don’t do anything. Your employer withholds 6.2% from each check, adds its own 6.2%, and sends the combined amount to the IRS. At year end, the total withheld from your pay appears in Box 4 of your W-2, labeled “Social security tax withheld.” For 2026, that box should not exceed $11,439.6Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3
If You’re Self-Employed
Independent contractors and sole proprietors owe the full 12.4% themselves, because no employer is covering the other half.1Social Security Administration. Contribution and Benefit Base You calculate it on Schedule SE as part of the broader self-employment tax, which also includes the Medicare portion.7Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) The $184,500 ceiling still applies.
The tax code lets you deduct the employer-equivalent half when calculating your adjusted gross income. That reduces your income tax but not the self-employment tax itself.7Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
Because no one is withholding for you, the IRS expects quarterly estimated payments. The 2026 deadlines are April 15, June 15, September 15, and January 15, 2027. You can generally avoid an underpayment penalty if you owe less than $1,000 at filing, or if you paid at least 90% of this year’s tax liability or 100% of last year’s. If your adjusted gross income exceeded $150,000, the prior-year safe harbor rises to 110%.8Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
If You Work More Than One Job
Each employer withholds 6.2% independently, with no visibility into what the others are doing. If your combined wages pass $184,500, you’ll overpay for the year. That money isn’t lost. You claim the excess as a credit on your Form 1040 when you file.9Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld
Different rule if one employer overwithholds on its own, say through a payroll mistake. You can’t recover that on your tax return. Ask the employer to correct it. If they won’t, file Form 843 with the IRS to request a refund directly.9Internal Revenue Service. Topic No. 608, Excess Social Security and RRTA Tax Withheld
Who Doesn’t Pay
Most workers in the United States pay OASDI. A handful of narrow categories do not.
- Members of a recognized religious sect that has opposed public or private insurance since before 1951, if the sect makes reasonable provision for its dependent members and the individual waives all rights to Social Security and Medicare benefits.10Social Security Administration. SSA Handbook 1128
- Foreign students on F-1, J-1, or M-1 visas who have been in the United States for fewer than five calendar years, on wages tied to their visa purpose. The exemption ends once they become resident aliens.11Internal Revenue Service. Foreign Student Liability for Social Security and Medicare Taxes
- Students enrolled at least half-time who work for the same college or university where they take classes. The exemption disappears if the student qualifies as a “professional employee” of the institution, meaning they are eligible for benefits like retirement plan participation or paid leave.12Internal Revenue Service. Student FICA Exception
- Household employees paid less than $3,000 in cash wages during 2026.13Social Security Administration. Employment Coverage Thresholds
Some state and local government employees hired before certain dates may also be outside the system if their employer never opted into Social Security coverage, though this covers a shrinking group.
Will the Money Be There Later
Social Security runs on a pay-as-you-go model: today’s workers fund today’s beneficiaries rather than building individual accounts. The system’s health depends on the ratio between the two.
According to the 2024 Social Security Trustees Report, the combined OASI and DI trust funds can pay 100% of scheduled benefits until 2035. After that, incoming payroll tax revenue would still cover about 83% of promised benefits.14Social Security Administration. Trustees Report Summary The program does not disappear at that point. Workers would keep paying OASDI, and those taxes would keep flowing to beneficiaries. Closing the remaining gap would require Congress to raise taxes, reduce benefits, or do both.