How long did the country go without a vice president?

The United States went without a vice president for a total of 19 years during its history. This occurred between 1849 and 1850, and then again from 1885 to 1886, as well as during various other periods when the vice presidency was vacant due to death or resignation. Most notably, the longest vacancy was from 1961 to 1963, when Lyndon B. Johnson assumed the presidency after John F. Kennedy's assassination. The vice presidency has often been left unfilled when a president dies or resigns, as there was no mechanism to fill the vacancy until the 25th Amendment was ratified in 1967.