The FM 300 designation continues north through Levelland on Avenue H for one mile (1.6 km), passing west of a lake before ending at Bus.

The highway runs through rural areas of Hockley and Lamb counties before entering the town of Sudan, where it meets US 84.

On May 21, 1953, the highway was reduced by 2.0 miles (3.2 km) to the Guadalupe River due to the construction of the Canyon Lake Dam.

The highway begins at SH 46 east of Bulverde and travels in a northwestern direction through the Smithson Valley region of Canyon Lake, intersecting FM 3159, before ending at US 281 in Spring Branch.

[18] A previous route numbered FM 313 was designated in Henderson County on June 11, 1945, from US 175 near LaRue to half a mile northeast of New York.

The highway was designated on June 11, 1945, running from SH 31 at Sand Springs eastward at a distance of 2.7 miles (4.3 km).

A previous route numbered FM 318 was designated on June 11, 1945, from Poyner north to Fincastle in Henderson County.

FM 324 was designated on June 11, 1945, to run from SH 94 in Lufkin south 2.5 miles (4.0 km) along the Old Diboll Road.

[59] A previous route numbered FM 327 was designated in Angelina County on June 11, 1945, from US 69 in Pollok southwest 6.7 miles (10.8 km) to SH 103.

RM 334 was designated as Farm to Market Road 334 (FM 334) on June 11, 1945, from US 90 in Brackettville northeastward 11.3 miles (18.2 km) toward Laguna.

RM 335 was designated on June 11, 1945, as Farm to Market Road 335 (FM 335) from the Edwards County line to Vance.

FM 339 was designated on June 23, 1945, running from Kirk southward across SH 164 to 2.0 miles (3.2 km) south of Ben Hur.

On November 24, 1959, the road was to be rerouted to end at FM 339 (which was extended north that day) when construction on that section was complete.

[82] The route travels to the south and then east, through Teaselville and close to the Cherokee County line into Bullard, where it intersects US 69.

[83] FM 344 continues to the northeast, to the community of Walnut Grove, before turning to the east and ending at SH 110 northwest of Troup.

On December 18, 2003, by district request, the road was extended 3.4 miles (5.5 km) to US 69 in Jacksonville, replacing a section of old US 175 and all of Spur 386.

[90] FM 350 passes by both the Livingston Municipal Airport and the Texas Department of Criminal Justice Polunsky Unit (the latter being the home of the state's death row for men).

On January 23, 1953 (connecting section designated December 17, 1952), the road was extended east to SH 94, replacing FM 948.

On June 15, 1954, the road was extended north to SH 6 near Navasota, replacing FM 245 (the connecting section was designated on March 24).

[110] The road travels east, roughly paralleling the Timber Rock Railroad to its south, and intersects SH 87 in Bleakwood.

FM 365 was designated on June 18, 1945, to run from SH 124 in Fannett eastward 9.3 miles (15.0 km) to the Spindletop Road.

On January 27, 1948, the road was extended west and north to US 90 in Nome and east and northeast to FM 366 in Port Neches.

A previous route numbered FM 374 was designated on June 25, 1945, from SH 199 in Megargel to a point 6.6 miles (10.6 km) northeast in Archer County.

On November 23, 1954, the road was extended southwest 43 miles (69 km) into Tom Green and Irion counties to US 67 in Barnhart, replacing FM 2008.

FM 380 was designated on June 11, 1945, as Ranch to Market Road 380 (RM 380) from San Angelo to Paint Rock.

On June 27, 1995, the section west of Loop 306 was internally redesignated as Urban Road 388 (UR 388), but reverted to FM 388 on November 15, 2018.

[158][159] FM 390 generally follows along a portion of the much older La Bahía Road from western Louisiana into southeast Texas used before European settlement.

A previous route numbered FM 394 was designated on June 16, 1945, from La Pryor to Batesville as a replacement of a portion of SH 76.

A previous route numbered FM 396 was designated in Yoakum County on June 11, 1945, from SH 214 5 miles (8.0 km) north of Denver City, east to Bennett.

A previous route numbered FM 398 was designated on June 11, 1945, from US 380 west of Post south to Graham Chapel in Garza County.