The contribution rate for employees, their employers, and the self-employed, is .90 percent of covered earnings through 1977. It then increases gradually reaching a maximum of 1.45 percent in 1986 and subsequent years. These amounts are added to, and are paid at the same time as the other social security contribution rates (FICA).

The contributions collected become part of a trust fund from which all Part A payments are made. This fund is administered by a Board of Trustees consisting of the Secretary of the Treasury (who is the Managing Trustee), the Secretary of Labor, and the Secretary of Health and Human Services all ex-officio. The Managing Trustee is authorized to invest trust funds only in interest-bearing obligations of the United States, or in obligations guaranteed as to both principal and interest by the United States not need for current withdrawals, and to make payments from the fund for purposes of Part A, including administrative expenses.