Thomas Phillip O'Neill III (born September 20, 1944)[1] is an American politician and businessman who served as the 65th lieutenant governor of Massachusetts.

Born in Cambridge, Massachusetts, he is a son of Mildred Anne Miller and Thomas Phillip "Tip" O'Neill Jr., who served as Speaker of the United States House of Representatives from 1977 to 1987.

O'Neill received his bachelor's degree from Boston College and earned his Master of Public Administration from Harvard University’s John F. Kennedy School of Government.

Prior to becoming lieutenant governor, O’Neill served as a member of the Massachusetts House of Representatives from 1973 to 1974.

O'Neill declined to seek a third term in 1982 in order to run for Governor of Massachusetts, but ran afoul of the state Democratic Party's rule changes and failed to make the ballot.