The U.S. Congressional Budget Office (CBO) has estimated that if same-sex marriages were legalized in all 50 states and recognized by the federal government, the federal budget would gain almost $1 billion a year in new revenue.
Based on the responses to Census 2000, CBO estimated that nearly 600,000 same-sex couples nationwide would get married if they had the opportunity, and that those 600,000 newly married couples would pay up to an additional $700 million a year, mainly in income and estate taxes.
Currently, and as long as the Defense of Marriage Act remains in effect, the federal government does not recognize marriages of same-sex couples either for receipt of federal benefits or for tax purposes. Under the law, the federal government honors only marriages between one man and one woman.
In almost-broke California, where voters just overrode the state's supreme court by re-outlawing same-sex marriage, a University of California study estimated that gay weddings would generate $64 million in additional state tax revenue and create some 2,200 new jobs.