What is Social Security Tax?

Social Security tax, officially called OASDI (Old-Age, Survivors, and Disability Insurance), is a 6.2% tax on your gross wages up to the annual wage base limit ($168,600 in 2026). This tax funds monthly benefits for retirees, disabled individuals, and survivors of deceased workers. Once you earn above the wage base, you stop paying Social Security tax for the rest of the year — which is why high earners may notice their paychecks getting slightly bigger late in the year.