How many types of Social Security trust funds exist?

The number of types of Social Security trust funds is two. These two types are the Old-Age and Survivors Insurance (OASI) Trust Fund, which pays benefits to retired workers and their families, and the Disability Insurance (DI) Trust Fund, which provides benefits to disabled workers and their families. This structure reflects the different purposes these funds serve within the Social Security system, with each fund drawing from its own sources of income, primarily through payroll taxes.

Understanding the distinction between these two funds is crucial because it helps clarify how Social Security addresses the diverse needs of the population it serves, such as retirement benefits and disability benefits. Each trust fund operates independently, and the funds are not interchangeable; thus, knowing that there are only two types illustrates the compartmentalization within the Social Security system designed to ensure that various benefits can be funded appropriately.