How many terms can a president serve?

A President can serve a maximum of two elected four-year terms, or up to ten years total if the President assumed office partway through someone else's term. This rule is set by the 22nd Amendment, ratified in 1951. The 22nd Amendment was a direct response to Franklin D. Roosevelt, who broke with George Washington's two-term tradition by being elected to a third term in 1940 and a fourth term in 1944 during World War II. Roosevelt died early in his fourth term in 1945.

After his presidency, many Americans, particularly Republicans who had opposed Roosevelt's expansion of federal power, supported a constitutional limit to prevent any future President from holding office for so long. The amendment was proposed by Congress in 1947 and ratified by the required three-fourths of state legislatures by 1951.

The full text limits a person to election as President twice. It also adds that no person who has held the office of President, or acted as President, for more than two years of a term to which some other person was elected President shall be elected to the office of the President more than once. This means a Vice President who succeeds to the presidency with two years or less remaining in the predecessor's term can still be elected to two full terms of their own, potentially serving up to ten years total. A Vice President who succeeds with more than two years remaining can only be elected to one additional term.

Lyndon Johnson, who became President after John F. Kennedy's assassination in November 1963, was the first to face this calculation. He completed Kennedy's remaining term, won election in 1964, and was eligible for one more term but chose not to run in 1968.

Before the 22nd Amendment, the two-term tradition rested entirely on Washington's example. Several Presidents, including Theodore Roosevelt and Ulysses S. Grant, considered third-term runs but did not pursue them. The amendment converted Washington's voluntary practice into binding constitutional law.