Shikoku Railway Company (JR Shikoku) owns and operates the line, whose name comes from the characters in the cities that the line connects: Takamatsu (高松) and Tokushima (徳島).

In addition to local trains that run the entire length of the Kōtoku Line, there are trains that run between Takamatsu and Orange Town, Sambommatsu, and Hiketa, as well as between Tokushima and Itano and Tokushima and Hiketa.

For a single-tracked line service levels are quite high, except along the prefectural border between Itano and Hiketa.

[citation needed] The Takamatsu to Hikida section was opened between 1925 and 1928 by the (then) Japanese Imperial Railways.

[citation needed] In 1933 the Awa Electric Railway was nationalised, and in 1935 the Hikida to Ikenotani and Yoshinari to Sako sections were opened, completing the line.