Most federal employees don't pay Social Security taxes, but some do

Whether a federal employee pays into Social Security depends on when they were hired and which retirement system covers them. Employees hired before 1984 almost never pay Social Security taxes. Those hired in 1984 or later usually do pay, but the rules differ between the two main federal retirement systems: the Federal Employees Retirement System (FERS) and the Civil Service Retirement System (CSRS).

The distinction matters because it changes how much you'll receive from Social Security later, what taxes come out of your paycheck now, and what other retirement income you're building. Understanding which system covers you is the first step to knowing what to expect.

Key Takeaways

  • Federal employees hired before 1984 under CSRS do not pay Social Security taxes and typically cannot receive Social Security benefits based on their federal work.
  • Federal employees hired in 1984 or later under FERS pay both Social Security and Medicare taxes, just like private-sector workers.
  • Some federal employees work under CSRS but were hired after 1984; these employees pay Social Security taxes but receive reduced benefits because they also have a federal pension.
  • Your pay stub will show whether Social Security tax (labeled OASDI) is being withheld — if it is, you're building a Social Security record.
  • Federal employees who don't pay Social Security may face a reduced benefit if they later work in a job that does pay into the system.

FERS employees and Social Security taxes

If you work under the Federal Employees Retirement System (FERS), you pay Social Security taxes regardless of your hire date. FERS was created in 1984 specifically to align federal retirement with the Social Security system. Every FERS employee has Social Security tax withheld from their paycheck, labeled OASDI (Old-Age, Survivors, and Disability Insurance).

FERS employees pay the same Social Security tax rate as private-sector workers: 6.2 percent of wages up to the annual wage cap, plus 1.45 percent for Medicare. Your employer (the federal government) matches these amounts. This means you're building a standard Social Security record while also participating in FERS, which provides a pension and a Thrift Savings Plan (TSP) account similar to a 401(k).

Because you pay in, you can receive a Social Security benefit at retirement age based on your federal earnings. The amount depends on how long you worked under FERS and your average earnings, just as it would for any other worker.

CSRS employees and the Social Security exemption

If you were hired before 1984 under the Civil Service Retirement System (CSRS), you do not pay Social Security taxes. CSRS was the federal retirement system before FERS existed, and it was designed as a complete replacement for Social Security rather than a supplement to it. Employees under CSRS have no OASDI withholding on their paychecks.

Because CSRS employees don't pay in, they generally cannot receive a Social Security benefit based on their federal work. However, if a CSRS employee worked in a non-federal job that paid Social Security taxes, they may be may have access to to a benefit from that work. The amount would be calculated based only on those non-federal earnings.

CSRS provides a pension calculated differently than FERS — typically more generous for long-term employees — which was intended to serve as the sole retirement income from federal service. If you're a CSRS employee nearing retirement, your pension statement will show your projected monthly benefit.

CSRS employees hired after 1984

A smaller group exists: federal employees hired in 1984 or later who work under CSRS rather than FERS. This happened in specific circumstances, usually when someone transferred into federal service from another government job or was rehired after a break. These employees pay Social Security taxes but still receive a CSRS pension.

If you're in this situation, you pay Social Security tax on your federal salary and build a Social Security record. However, your eventual Social Security benefit may be reduced by the Government Pension Offset (GPO) or Windfall Elimination Provision (WEP), rules that lower Social Security benefits for people who also receive a government pension. You should receive a notice from Social Security explaining this reduction before you claim benefits.

How to find out which system covers you

Your most recent pay stub will show whether Social Security tax is being withheld. Look for a line labeled OASDI or Social Security. If an amount appears there, you're paying in and building a Social Security record. If that line is blank or shows zero, you're not paying Social Security tax.

You can also check your official personnel file through your agency's HR office, or contact the Office of Personnel Management (OPM) directly. OPM maintains records of all federal employees and can confirm which retirement system covers you. Your agency's benefits office can also answer this question quickly.

Another way to verify: create an account on ssa.gov and view your Social Security Statement. If you have federal earnings listed, you were paying into Social Security during that time. If your federal employment years show no earnings, you were under CSRS and not paying in.

What happens if you move between systems

If you transfer from CSRS to FERS, or from a non-federal job to federal employment, your Social Security record follows you. Any years you paid Social Security tax — whether federal or non-federal — count toward your benefit. Social Security doesn't care where you worked; it only counts the taxes you paid.

However, if you spent years under CSRS without paying Social Security tax, those years don't count toward your benefit. Your Social Security benefit will be based only on the years you did pay in. This is one reason why federal employees who switch systems partway through their career sometimes have lower Social Security benefits than they expected.

If you worked in both federal and non-federal jobs, and some years were under CSRS (no Social Security tax), your benefit will reflect only the years you paid in. Social Security will calculate your benefit based on your 35 highest-earning years across all jobs where you paid the tax.

Government Pension Offset and Windfall Elimination Provision

Two rules can reduce the Social Security benefit of federal employees who also have a government pension: the Government Pension Offset (GPO) and the Windfall Elimination Provision (WEP). These explore mainly to CSRS employees and some FERS employees in specific situations.

The GPO reduces or eliminates a spouse's or survivor's Social Security benefit if the person receiving it also gets a government pension. For example, if a CSRS employee's spouse is may have access to to a benefit as a spouse, that benefit may be reduced by two-thirds of the government pension amount.

The WEP reduces your own Social Security benefit if you receive a government pension and also paid Social Security tax in other work. The reduction is typically 25 to 50 percent of your benefit, depending on how much non-government work you had. Social Security will notify you of any reduction before you claim benefits.

Frequently Asked Questions

Can a federal employee receive both a CSRS pension and Social Security?

A CSRS employee who worked in non-federal jobs that paid Social Security tax can receive both a CSRS pension and a Social Security benefit based on that non-federal work. However, the Social Security benefit may be reduced by the Government Pension Offset if the person is claiming as a spouse or survivor rather than on their own work record.

If I'm a FERS employee, will my Social Security benefit be reduced because I have a federal pension?

Most FERS employees are not affected by the Windfall Elimination Provision or Government Pension Offset because FERS was designed to work alongside Social Security. However, if you also worked in a non-federal government job (such as for a state or local government) that paid a pension, you may face a reduction. Check your Social Security Statement or contact Social Security directly to confirm.

What if I was a CSRS employee and never paid Social Security tax?

You can still receive a Social Security benefit if you worked in other jobs — federal contractor work, self-employment, or private-sector jobs — where you paid Social Security tax. Your benefit would be based only on those earnings, not on your CSRS federal service. If you have no other work history with Social Security tax, you would not receive a Social Security benefit.

How do I know if the Windfall Elimination Provision will affect me?

You can view your Social Security Statement at ssa.gov to see if WEP is noted. You can also call Social Security at 1-800-772-1213 and ask whether your record shows a government pension that would trigger WEP. Social Security will send you a notice before you claim benefits if a reduction applies.

Can I change from CSRS to FERS to pay Social Security taxes?

CSRS employees cannot switch to FERS voluntarily. However, if you leave federal service and return later, you may be hired under FERS. If you're considering a career move, speak with your agency's benefits office about how it would affect your retirement system and Social Security record.