The routing of NY 28N was originally designated, but not signed, as part of legislative Route 25 in 1908. In 1924, the portion of Route 25 from Long Lake to North Creek was designated as part of the signed NY 10. The segment of former Route 25 between Blue Mountain Lake and Long Lake became part of NY 10A in the late 1920s. In the 1930 renumbering, the NY 10A designation was eliminated, and NY 10 was rerouted south of Long Lake to follow the modern routing of NY 30 south to Speculator. The former routing of NY 10 between Long Lake and North Creek was then administratively redesignated as NY 28N, which continued southward from Long Lake to Blue Mountain Lake by way of an overlap with NY 10.