NY 26 was split into several different routes as part of the 1930 renumbering of state highways in New York. The segment of former NY 26 between US 20 in Skaneateles and NY 5 in Camillus was renumbered to NY 321.
In 1930, the New York State highway system underwent a major renumbering project. This resulted in the segment of former NY 26 between US 20 in Skaneateles and NY 5 in Camillus being assigned the new designation NY 321.