Explainers/Government
The 25th Amendment, explained: how presidential succession and disability actually work
The amendment sets out four separate procedures — for succession, for filling a vice presidential vacancy, and for handling a president who is unable to serve. Here is what each section says and what it requires.
7 min read|Updated August 5, 2026
Ratified on February 10, 1967, the Twenty-fifth Amendment to the U.S. Constitution answers questions the original text left unsettled: what happens when a president dies, resigns or is removed; how a vice presidential vacancy is filled; and what to do when a president is unable to discharge the powers and duties of the office. It contains four sections. Section 1 makes the vice president the president in cases of removal, death or resignation. Section 2 lets the president nominate a new vice president, subject to majority confirmation by both chambers of Congress. Section 3 lets a president voluntarily and temporarily transfer power. Section 4 allows the vice president together with a majority of the Cabinet to declare the president unable to serve, a step that has never been used and that Congress can be called on to resolve by a two-thirds vote in both chambers.
- Ratified
- February 10, 1967, after being proposed by Congress in July 1965 in the wake of President John F. Kennedy's assassination.
- Sections
- Four. Succession (1), vice presidential vacancy (2), voluntary transfer of power (3), and involuntary declaration of inability (4).
- Times used
- Section 1 once (1974), Section 2 twice (1973 and 1974), Section 3 four times (1985, 2002, 2007, 2021). Section 4 has never been invoked.
- Section 4 threshold
- The vice president plus a majority of principal executive department heads. If the president disputes it, Congress must decide, and a two-thirds vote of both chambers is required to keep the president sidelined.
What does Section 1 do?
Section 1 states that if the president is removed from office, dies or resigns, the vice president becomes president — not merely acting president. That distinction mattered historically: when William Henry Harrison died in 1841, it was not settled whether John Tyler was the president or only exercising the office's powers. Tyler's claim to the full office became known as the Tyler Precedent, and Section 1 wrote it into the Constitution. It was formally applied in August 1974, when Richard Nixon resigned and Gerald Ford became president.
What does Section 2 do?
Section 2 provides that whenever the vice presidency is vacant, the president nominates a vice president who takes office upon confirmation by a majority vote of both the House and the Senate. Before 1967 the office simply sat empty for the remainder of a term, which happened 16 times. It has been used twice: Nixon nominated Gerald Ford after Spiro Agnew resigned in October 1973, and Ford nominated Nelson Rockefeller after becoming president in 1974. The result was that for roughly two years neither the president nor the vice president had been elected to those offices.
What does Section 3 do?
Section 3 lets a president voluntarily hand power to the vice president by sending a written declaration to the Senate president pro tempore and the Speaker of the House. The vice president serves as acting president until the president transmits a second written declaration reclaiming the office. It has been used explicitly four times, all for scheduled medical procedures requiring anesthesia: Ronald Reagan in 1985, George W. Bush in 2002 and 2007, and Joe Biden in 2021. Reagan's letter said he was not necessarily setting a precedent, though later presidents followed the same practice.
What does Section 4 do, step by step?
Section 4 covers cases in which a president is unable to serve but does not say so. The vice president and a majority of the heads of the executive departments — or of another body Congress designates by law — transmit a written declaration of inability to the Senate president pro tempore and the Speaker. The vice president then immediately becomes acting president. If the president transmits a counter-declaration stating that no inability exists, the president resumes power unless the vice president and the same Cabinet majority repeat their declaration within four days. Congress must then assemble within 48 hours if not in session and decide the question within 21 days. Only a two-thirds vote in both the House and the Senate keeps the vice president as acting president; otherwise the president resumes the office. Section 4 has never been invoked.
Does the amendment define what counts as inability?
No. The text says only that the president is "unable to discharge the powers and duties of his office" and does not define the term or set a medical standard. The 1965 congressional debate indicates the drafters intended it to cover both physical and mental incapacity, and deliberately left the judgment to the officials named in the text rather than to doctors or courts. Because Section 4 has never been used, there is no precedent applying that standard to a specific case.
Is the 25th Amendment a substitute for impeachment?
They are separate mechanisms with different purposes. Impeachment, under Article I and Article II, is a congressional process addressing treason, bribery, or other high crimes and misdemeanors, and removal is permanent. Section 4 of the 25th Amendment addresses inability to perform the job, not misconduct; the president is not removed from office, remains president, and can reclaim the powers of the office by transmitting a declaration. Legal scholars who have testified before Congress on the point generally agree the amendment was not designed as a remedy for unfitness in the political sense.
What is the "other body" Congress could designate?
Section 4 permits Congress to establish, by law, an alternative body to act in place of the Cabinet in the declaration. Congress has never enacted such a law. Bills to create a standing commission on presidential capacity have been introduced periodically by members of both parties — including proposals in the 1990s and again in the 2010s and 2020s — but none has been enacted. Absent such a statute, the Cabinet remains the only body that can join the vice president in a Section 4 declaration.
How does this relate to the Presidential Succession Act?
The 25th Amendment governs the vice president's role. The Presidential Succession Act of 1947 governs what happens beyond that: the Speaker of the House, then the Senate president pro tempore, then Cabinet secretaries in order of their departments' creation. The amendment's Section 2 reduces how often that statutory line is likely to be reached, because a vice presidential vacancy can now be filled rather than left open.