According to the Social Security Administration, undocumented workers contributed over $100 billion in payroll tax (FICA) contributions to the Social Security Trust funds in the past decade. In 2010 alone, these workers paid an estimated $13 billion in Social Security taxes, but only received $1 billion in benefits. These payments are made when the estimated several millions of undocumented workers who use false or expired Social Security numbers are also having payroll taxes automatically deducted from their paychecks. The net contribution to the health of the Social Security trust fund was $12 billion in 2010. Because these individuals are not legally entitled to work in the U.S., however, they will not likely benefit in the future from their contribution to Social Security benefits. While there are commonly-held perceptions that illegal workers drain the economy, these numbers show their net positive effect on the health of Social Security’s ledgers.
Source: SSA, Office of the Chief Actuary