State Highway 138, or SH 138, runs from 1 miles (1.6 km) north of Florence

Florence, Texas

Florence is a city in Williamson County, Texas, United States. The population was 1,054 at the 2000 census, and 1,109 in the 2005 census estimate.-Geography:Florence is located at...

 west about 6.3 miles (10.1 km) to U.S. Highway 183. The highway was originally part of SH 195

State Highway 195 (Texas)

State Highway 195, or SH 195, is a state highway in the U.S. state of Texas that runs from FM 439 in Killeen, south to Interstate 35 in Georgetown. In Killeen it is known as Fort Hood Street; in Florence it is called Patterson Avenue...

. When SH 195 was redirected north of Florence to Killeen over RM 440 in 1988, this portion was redesignated as SH 138.

Previous routes

SH 138 was previously designated by 1933 as a short connector route in Childress County, cosigned with U.S. Highway 62. By 1939, the designation had been cancelled in favor of US 62.