The 25th Amendment, Section 1, clarifies Article II, Section 1, Clause 6, by stating unequivocally that the vice president is the direct successor of the president, and becomes president if the incumbent dies, resigns or is removed from office. It also, in sections 3 and 4, provides for situations where the president is temporarily disabled, such as if the president has a surgical procedure or becomes mentally unfit. Additionally, in Section 2, the amendment provides a mechanism for intra-term vice presidential succession, establishing that vice presidential vacancies will be filled by the president and confirmed by both houses of Congress. Previously, whenever a vice president had succeeded to the presidency or had died or resigned from office, the vice presidency remained vacant until the next presidential and vice presidential terms began; there were 16 such vacancies prior to 1967.
who becomes the vice president if the president is impeached
filled by the president and confirmed by both houses of Congress