The legislation was sponsored by current Speaker John Boehner and his predecessor as Speaker, Nancy Pelosi.
The building that will bear O'Neill's name is located just southwest of the Capitol, adjacent to the Gerald R. Ford House Office Building and the Hubert H. Humphrey Building that houses the Department of Health and Human Services.
O'Neill represented his Boston-area district from 1953-1987. As speaker, the liberal Democrat is remembered for his quote "all politics is local" and for his ability to work with the conservative President Ronald Reagan. The centennial of his birth is on Dec. 9. He died in 1994.