If a president is removed from office after being impeached, when does the vice president take office?
Upon removal from office, under Article II, Section 1 paragraph 6, the duties of the president devolve upon the vice president.
In Case of the Removal of the President from Office, or of his Death, Resignation, or Inability to discharge the Powers and Duties of the said Office, the Same shall devolve on the Vice President, and the Congress may by Law provide for the Case of Removal, Death, Resignation or Inability, both of the President and Vice President, declaring what Officer shall then act as President, and such Officer shall act accordingly, until the Disability be removed, or a President shall be elected.
Later, the vice president, under Article II, Section 1, paragraph 8, takes the oath or affirmation and becomes president.
Before he enter on the Execution of his Office, he shall take the following Oath or Affirmation:-"I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my Ability, preserve, protect and defend the Constitution of the United States."
Compare to the death of President Kennedy and Vice President Johnson becoming president. There was a time delay to bring a Federal judge to Air Force One for the oath or affirmation.
Or, the more recent resignation of Nixon making Ford president. Nixon resigned effective 11:35 a.m. Ford became president during a ceremony held at noon. For approximately 25 minutes, Ford was acting president. (The 25th Amendment was in effect.)
Richard M. Nixon’s Resignation Letter, 08/09/1974.
Following the revelations stemming from the investigation of the Watergate break-in, President Richard M. Nixon resigned the Presidency in this letter dated August 9, 1974. The President's resignation letter is addressed to the Secretary of State, in keeping with a law passed by Congress in 1792. The letter became effective when Secretary of State Henry Kissinger initialed it at 11:35 a.m.
Presidential Vacancy and Disability Twenty-Fifth Amendment.
President Richard M. Nixon resigned his office August 9, 1974, and Vice President Ford immediately succeeded to the office and took the presidential oath of office at noon of the same day.
Swearing in Ceremony of Gerald R. Ford as 38th President of the United States, August 9. 1974 (youtube video).
At 0:53, Chief Justice Burger referred to Ford as Mr. Vice President.
An oath was taken.
At 1:33, Chief Justice Burger referred to Ford as Mr. President.
In the United States, if during an impeachment trial the Senate votes to convict the president, when does the vice president take office as the new president? Is is immediately after a vote is taken, or is there a waiting period?
Only a time delay for the ceremony.
Also, if there is a waiting period, is the impeached president still in office during that time or is there no president in between when the first president is convicted and when the new one takes office?
Removal from office is immediate. There is always a president or one having the duties of the president.