For the United States, the Totalization agreement applies to Social Security taxes
related to the Retirement, Survivors and Disability insurance (RSDI) program (i.e.,
Federal Insurance Contributions Act (FICA) taxes for employment and Self Employment
Contributions Act (SECA) taxes for self-employment, including the Medicare portion).
Thus, if an employee is exempt from U.S. Social Security coverage under this agreement,
neither the employee nor employer has to pay their share of the FICA tax as long as
the exemption is effective. A self-employed individual is also exempt from paying
SECA taxes (equivalent to the employee and employer share of the FICA tax) for any
period the exemption is effective.