[3] As it leaves Dewar, US 266 turns northeast, crossing Coal Creek and the Deep Fork River.

The highway heads due east out of Checotah, descending a ridge and passing just south of its summit, Mt.

Just under 3 miles (4.8 km) east of the McIntosh–Muskogee county line, US 266 intersects the southern Oklahoma State Highway 2 (SH-2).

Continuing straight puts the traveler on westbound US 64 toward Tulsa, while turning right brings the motorist onto eastbound US 64 toward Fort Smith, Arkansas.

[6] Upon the US route system's inception, US 266 replaced SH-9 from its junction with US 66 at 23rd Street and Lincoln Boulevard in Oklahoma City to US 64 in Warner.