Every two years, when the legislature met, new roads were added, at first by number, and later giving the SRD the ability to choose a number.

Up to and including 1939, every road written into law by the legislature was given a number by the SRD.

This included the range from SR 397 to SR 449, which included most of the 1926 Bond Issue Roads in Orange County and some other major roads.

A state law passed in 1941 authorized a renumbering; this didn't happen until 1945, also because of the war.

Current Florida State Roads are on a separate page.