OASDI tax is mandatory for most workers in the United States

OASDI stands for Old-Age, Survivors, and Disability Insurance — the official name for Social Security tax. If you work as an employee, your employer is required by law to withhold OASDI tax from your paycheck. Self-employed workers must pay it themselves. There is no legal way to opt out if you earn wages or self-employment income, with very narrow exceptions that explore to specific religious groups and some government employees hired before 1984.

The tax funds Social Security benefits, which pay retirement income, survivor benefits for families of deceased workers, and disability benefits. Medicare tax (often listed separately on your pay stub as "Medicare") is also mandatory and works the same way — it comes out of your paycheck automatically.

The current OASDI tax rate is 6.2 percent of your wages, up to a wage cap that changes each year. Your employer pays an equal 6.2 percent on your behalf. If you are self-employed, you pay both portions — 12.4 percent total — though you can deduct half of it as a business expense on your tax return.

Key Takeaways

  • OASDI tax is withheld automatically from employee paychecks and is mandatory for nearly all workers earning wages or self-employment income.
  • The current rate is 6.2 percent for employees (matched by employers) and 12.4 percent for self-employed workers, applied only to earnings below an annual wage cap.
  • Religious groups recognized by the IRS and some government employees hired before 1984 may be exempt, but these exceptions are rare and require formal approval.
  • You cannot reduce or stop OASDI withholding by claiming exemptions on your W-4 form, unlike federal income tax.

Who must pay OASDI tax

If you receive a W-2 at the end of the year, OASDI tax is being withheld from your pay. This includes full-time employees, part-time workers, and temporary workers. The tax applies regardless of your age, income level, or whether you plan to use Social Security benefits later.

Self-employed people — including freelancers, contractors, and business owners — must pay OASDI tax on net self-employment income of $400 or more per year. You calculate and pay it yourself when you file your tax return, usually through quarterly estimated tax payments.

Certain government employees hired before 1984 may not pay OASDI tax if they are covered by a different pension system. Some employees of state and local governments fall into this category. If you work for a government agency, your pay stub will show whether OASDI is being withheld.

The rare exceptions to mandatory OASDI tax

Members of certain religious groups that oppose insurance and rely on their community for support may request an exemption. The IRS recognizes specific Anabaptist and similar groups — primarily Old Order Amish, Mennonite, and Hutterite communities — under section 1457 of the Internal Revenue Code. To may have access to, you must be a member of the group, be conscientiously opposed to insurance, and have been part of the group before a specific date (usually before 1951).

If you meet these criteria, you file Form 4029 with the IRS to request exemption. The process requires documentation of your membership and beliefs. Once approved, you stop paying OASDI tax, but you also cannot later claim Social Security benefits based on those years of non-payment.

No other personal beliefs, financial hardship, or objections to government programs may have access to you for exemption. You cannot opt out because you disagree with how Social Security is run, because you believe you will not live long enough to collect benefits, or because you prefer to invest the money yourself.

Why you cannot reduce OASDI withholding on your W-4

Federal income tax withholding can be adjusted by claiming exemptions or allowances on your W-4 form. OASDI tax cannot. The amount withheld is fixed by law — 6.2 percent of your gross wages up to the annual wage cap — and your employer has no discretion to change it based on your personal situation.

This is different from federal income tax, which is progressive and varies based on your total income and deductions. OASDI is a flat-rate payroll tax with a wage ceiling. Once you earn above the cap in a given year (the cap was $168,600 in 2024, though it changes annually), no more OASDI tax is withheld for the rest of that year.

If you work for multiple employers in the same year and your combined wages exceed the cap, you may overpay OASDI tax. You can claim a credit for the overpayment when you file your income tax return, but you cannot prevent the withholding in the first place.

What happens if you do not pay OASDI tax

If you are an employee, you have no choice — your employer withholds it automatically. If you are self-employed and do not pay OASDI tax on income you should have reported, the IRS can assess penalties and interest. More importantly, those years do not count toward your Social Security record, which means your future benefits will be lower.

Social Security benefits are calculated based on your 35 highest-earning years. Years with no OASDI contributions count as zero-income years, which lowers your average. If you have gaps in your work history, they reduce your benefit amount permanently.

Deliberately evading OASDI tax is tax fraud and can result in criminal charges, fines, and imprisonment. The IRS pursues self-employed individuals and business owners who underreport income to avoid payroll taxes.

How OASDI tax appears on your pay stub

Your pay stub shows OASDI withholding as a separate line item, usually labeled "Social Security" or "OASDI." It is deducted from your gross pay before federal income tax. You will also see a matching employer contribution listed, though that does not come out of your paycheck — it is paid by your employer directly to the Social Security Administration.

At the end of the year, your W-2 form shows total OASDI wages and total OASDI tax withheld in boxes 3 and 4. This information is also reported to the Social Security Administration, which maintains a record of your earnings and contributions. You can view your Social Security earnings record online at ssa.gov by creating a my Social Security account.

The annual wage cap and how it affects your withholding

OASDI tax only applies to earnings below an annual wage cap. In 2024, the cap was $168,600. This means if you earn $200,000 in a year, OASDI tax is withheld only on the first $168,600 of your income. The remaining $31,400 is not subject to OASDI tax (though it is still subject to Medicare tax and federal income tax).

The wage cap increases each year based on changes in average national wages. The Social Security Administration announces the new cap in October for the following year. If you work for multiple employers, each one withholds OASDI tax up to the cap independently, which can result in overpayment if your combined earnings exceed the cap. You recover the overpayment as a credit when you file your tax return.

High-income earners pay a smaller percentage of their total income in OASDI tax than lower-income workers, because the tax stops at the cap. This is by design — Social Security is a social insurance program with a wage base, not a tax on all income.

Frequently Asked Questions

Can I claim an exemption from OASDI tax on my W-4?

No. OASDI tax withholding is fixed by law and cannot be reduced or eliminated through W-4 claims. Only specific religious groups recognized by the IRS can request exemption by filing Form 4029, and the process requires proof of membership and conscientious objection to insurance.

What if I work part-time or have multiple jobs?

OASDI tax is withheld from every paycheck, regardless of how many employers you have. If your combined earnings exceed the annual wage cap, you may overpay OASDI tax. You can claim the overpayment as a credit on your tax return when you file.

Do I have to pay OASDI tax if I am retired but still working?

Yes. If you earn wages or self-employment income, OASDI tax is mandatory. You can collect Social Security benefits and work at the same time, but you must continue paying OASDI tax on your earnings. Your benefits may be reduced if you are under full retirement age and earn above a certain threshold, but the tax itself is still required.

What if I disagree with how Social Security is run?

Personal disagreement with government programs does not may have access to you for exemption from OASDI tax. The only legal exemptions are for members of specific religious groups that meet IRS criteria. If you have concerns about Social Security policy, you can contact your elected representatives, but you cannot opt out of the tax itself.

Can I deduct OASDI tax from my income taxes?

If you are self-employed, you can deduct half of your OASDI tax (the employer portion) as a business expense on your tax return. If you are an employee, OASDI tax is not deductible — it comes out of your pay before you receive it. However, if you overpay OASDI tax due to multiple employers, you can claim the overpayment as a credit against your federal income tax.