SH 188 was established in its current form in 1992, after a previous incarnation existed from 1932 to 1942.

SH 188 was previously designated on November 30, 1932, as a connector route between then-SH 5 and Roxton.

[2] This route was canceled on April 29, 1942, and was replaced by FM 38.

SH 188 was designated on December 22, 1992, replacing part of FM 881 and part of FM 1069, of which SH 188 was concurrent with.

[1] Media related to Texas State Highway 188 at Wikimedia Commons