With the 2004 legalization of same-sex marriage in Massachusetts, many have questioned how the legalization of such marriages at the state level may affect the eligibility for and payment of federal Social Security benefits and private pensions. Social Security benefits are currently paid to the spouses of disabled, retired, or deceased workers entitled to Social Security. However, under current law, same-sex spouses are not eligible for Social Security benefits because they are unable to meet the gender-based definitions of “wife” and “husband” in the Social Security Act and the gender-based definition of “marriage” established by the Defense of Marriage Act. Federal employee pensions and private-sector pensions regulated by the Employee Retirement Income Security Act (ERISA) are required to provide certain benefits to the spouse of a participant in the event of the participant’s death. Under the Defense of Marriage Act, both federal pensions and private-sector pensions regulated by ERISA are required to define a spouse only as “a person of the opposite sex who is a husband or a wife.” This report will be updated as legislative activity warrants.