Who was the only U.S. president elected unanimously by the Electoral College?

George Washington was the only U.S. president elected unanimously by the Electoral College.

Washington received every electoral vote in both the 1788–1789 election and the 1792 election. The first election was conducted under the original constitutional system, in which each elector cast two votes for president; the candidate with the most votes became president and the runner-up became vice president.

John Adams finished second in the first election and became vice president. Washington’s unanimous support reflected his national reputation as commander of the Continental Army, presiding officer of the Constitutional Convention, and a leader viewed by many supporters of the new government as above ordinary factional politics.

The constitutional election system changed after the disputed election of 1800. The Twelfth Amendment, ratified in 1804, required electors to cast separate votes for president and vice president. Later presidents won large majorities, but no other president matched Washington’s unanimous Electoral College result.