Social Security Tax
Social Security uses FICA wages. Medical and FSA/HSA deductions reduce the wage base; 401(k) contributions do not.
The wage base limits one person's earnings for the year, not a household's. Each person on a return carries a base of their own, so a joint return with two earners applies the cap to each spouse separately rather than to their combined wages.
Subtract Social Security-exempt deductions from one person's gross wages, added together across every job they held:
Limit that person's Social Security wages to the annual wage base:
Apply the Social Security rate to taxable Social Security wages:
Add every person's tax to get the tax for the return:
Compare that total with the Social Security tax every employer withheld:
Each employer withholds as though it were the only one, which is why two returns with the same combined wages can end differently. One person holding two or more jobs can pass the wage base across those jobs: more was withheld than is owed, and the excess is refundable on the return. Two spouses who each stay under the base owe every dollar withheld, however far their combined wages sit above a single base.
Use this table to review the 2025 Social Security rate and wage base:
| 2025 item | Value |
|---|---|
| Employee rate | 6.2% |
| Wage base | $176,100 |
| Wage base applies | Per person |
| Maximum employee Social Security tax | $10,918.20 |