The OASDI line on your paycheck is a federal payroll tax that funds Social Security, and it is taken out because federal law requires it on almost every covered job. The letters stand for Old-Age, Survivors, and Disability Insurance. You pay 6.2% of your gross wages, your employer pays a matching 6.2%, and the money goes to the trust funds that send monthly checks to roughly 71 million retirees, surviving family members, and disabled workers. In most jobs, you cannot opt out.
What the Tax Actually Pays For
OASDI funds three separate benefit programs out of the same paycheck deduction:
- Old-Age (retirement): Monthly income for workers who have earned enough credits and reached at least age 62. A spouse, including one who never worked, can collect up to half of the retired worker’s full benefit.
- Survivors: Payments to a deceased worker’s dependents, including a surviving spouse and unmarried children under 18 (or under 19 if still in high school).
- Disability Insurance: Income replacement for workers who can no longer work because of a qualifying medical condition. The benefit equals what the worker would have received at full retirement age.
So the deduction is doing two things at once. It pays current beneficiaries, and it builds your own record for the day you claim retirement, become disabled, or leave dependents behind.
How Much Comes Out
The rate is 6.2% of your gross wages on every paycheck, applied until your year-to-date earnings reach the annual wage base limit. For 2026, that ceiling is $184,500. Cross it, and OASDI withholding stops for the rest of the calendar year, then starts again in January. The cap rises most years with the national average wage index. It was $168,600 in 2024 and $176,100 in 2025.
Someone earning $80,000 pays 6.2% on every dollar, or $4,960 for the year. A worker at or above the cap in 2026 pays a maximum of $11,439.00.
OASDI comes off your gross pay, not your take-home. A few things about that gross figure matter:
- Section 125 cafeteria plan contributions, such as employer-sponsored health premiums or a flexible spending account, are excluded before OASDI is calculated, so they lower the tax.
- Traditional 401(k) contributions do not. Those reduce your federal income tax, but Social Security still counts those dollars.
- The employee share of OASDI is not deductible on your federal income tax return.
Your Employer Pays the Same Amount
The 6.2% on your stub is only half of the contribution. Your employer pays a matching 6.2% that never appears on your pay statement, bringing the total OASDI going into the trust funds to 12.4% of your wages up to the cap.
OASDI is one piece of FICA, the Federal Insurance Contributions Act. The other piece is the Medicare tax:
- OASDI (Social Security): 6.2% employee plus 6.2% employer, applied up to $184,500 in 2026.
- Medicare: 1.45% employee plus 1.45% employer, applied to every dollar of wages with no cap.
Your total FICA withholding is 7.65% of wages up to the OASDI cap, dropping to 1.45% on wages above it. If your stub lists FICA-SS or Social Security instead of OASDI, it is the same tax.
Can You Opt Out?
For most workers, no. A few narrow categories are legally exempt.
Certain Government Employees
Federal workers hired before January 1, 1984, who stayed in the Civil Service Retirement System do not pay OASDI on their federal earnings. Anyone hired on or after that date falls under the Federal Employees Retirement System and pays OASDI like any private-sector worker. State and local coverage runs through voluntary Section 218 agreements between each state and the Social Security Administration, and coverage attaches to the position rather than the person. Whether a specific public job is covered depends on that state’s agreement.
Students Working at Their School
Students enrolled and regularly attending classes at a college or university are exempt from OASDI on wages earned from that same school, or from an organization operated exclusively for the school’s benefit. This is why many on-campus jobs for full-time students show no Social Security withholding.
Members of Certain Religious Groups
Members of recognized religious groups that have existed continuously since December 31, 1950, and that conscientiously oppose all forms of public and private insurance can apply for exemption using IRS Form 4029. Approval means no OASDI or Medicare tax, but it also permanently waives all Social Security and Medicare benefits.
Certain Nonresident Aliens
Foreign students and exchange visitors in F-1, J-1, or M-1 status who are still classified as nonresident aliens (generally their first five calendar years in the U.S.) are exempt from FICA on wages from visa-authorized employment. Once they become resident aliens, the exemption ends.
Work that does not pay into Social Security also does not earn benefit credits, no matter how much it pays.
What You Get for Paying It
Every dollar of OASDI tax you pay builds your work record with the Social Security Administration. You earn credits based on annual earnings. In 2026, each $1,890 in covered wages earns one credit, up to four credits per year. The threshold adjusts each year with the wage index.
Most workers need 40 credits, roughly ten years of work, to qualify for retirement benefits. Disability benefits require fewer credits, with the number depending on your age when you become disabled. Credits never expire. If you leave the workforce and come back, your earlier credits are still on your record.
If You Have Two Jobs, Watch for Overwithholding
If you work for a single employer, they stop withholding OASDI once your wages hit the annual cap. If you hold two or more jobs at the same time, each employer tracks the cap independently based only on what they pay you. You can end up with more than $11,439.00 withheld across all your jobs combined in 2026.
When that happens, you claim the excess as a credit on your federal income tax return. The Form 1040 instructions walk through the calculation under “Excess Social Security and tier 1 RRTA tax withheld.” If you file jointly, each spouse figures the excess separately. The IRS refunds the overpayment or applies it to any other tax you owe. Your employer will not refund the excess directly, so this is something to catch at tax time.