Pres. Donald Trump announced that he will not be attending the inauguration of Joe Biden.
How many presidents have not attended the inauguration of their successor?
This Raleigh News & Observer article listed those Presidents and their reasons for not attending their successors' inauguration.
It marked the first time in history the presidency was handed over to the opposing party, and Adams may have wanted to avoid stirring the pot between the Federalists and Democratic-Republicans, the association says.
It’s unclear why John Quincy Adams, the country’s sixth president, didn’t attend the inauguration of his successor, Andrew Jackson.
Adams didn’t invite Jackson to the White House when he arrived in Washington, D.C., on Feb. 11, according to The White House Historical Association. Jackson also didn’t “call on” Adams.
Grant and Johnson were nemeses, and Grant had previously said he would not ride in a carriage to the Capitol with Johnson, according to CNN. Johnson was also reportedly angry about his impeachment, according to NBC News.
Nixon, the only U.S. president to resign, informed then-Vice President Gerald Ford on Aug. 8 he planned to resign and that Ford would take office the next day.
At 9:30 a.m. Aug. 9, Nixon and his family entered the East Room of the White House where Nixon delivered his final address as president
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He then left the White House and boarded the presidential helicopter.
By the time Air Force One landed in California, Ford had been sworn in and Nixon was “an ordinary citizen,” History.com says.
In addition to the presidents mentioned in the answer by panda, none of the following Presidents attended the inauguration of the next President:
Each died in office. They did not, of course, choose to "skip" the next inauguration.