[6] Continuing north into Kent County, the route begins a concurrency with US 380 that lasts until Jayton.

[8][9] After heading almost due north from here, the route enters Motley County and passes through the town of Roaring Springs.

[13] SH 70 resumes a more northerly path into Donley County, and has a short concurrency with US 287 through Clarendon.

[14] After the two routes separate, SH 70 heads due north to a junction with Interstate 40 at its Exit #124, near the Donley–Gray County line.

[15] Northbound SH 70 is concurrent with the freeway for about 3.5 mi (5.6 km) before the routes split at I-40 Exit #121.

[16][17] SH 70 then enters Ochiltree County and reaches its northern terminus at US 83 south of Perryton.

The route was designated in 1990, when SH 70 was rerouted along the south and east side of the city to use the I-20 freeway.