U.S. Route 81
Route information
Length	1,220 mi[source?] (1,960 km)
Existed	1926, truncated to Fort Worth in the 1990s[source?]–present
Major junctions
South end	I-35W / US 287 at Fort Worth, TX
Major intersections	I-44 at Chickasha, OK I-40 at El Reno, OK I-135 from Wichita, KS to Salina, KS I-70 near Salina, KS I-80 at York NE I-90 at Salem, SD I-29 from Watertown, SD to Manvel, ND I-94 at Fargo, ND US 2 at Grand Forks, ND I-29 from Joliette, ND to Pembina, ND
North end	I-29 / PTH 75 at Pembina–Emerson Border Crossing near Pembina, ND
Location
Country	United States
States	Texas, Oklahoma, Kansas, Nebraska, South Dakota, North Dakota
Highway system
United States Numbered Highway System List Special Divided

U.S. Route 81 or U.S. Highway 81 (US 81) is a major north–south U.S. highway. It goes for 1,220 miles (1,960 km) in the central United States. It is one of the original United States Numbered Highways created in 1926 by the American Association of State Highway Officials.

The route of US 81 follows that of the old Meridian Highway which dates back as early as 1911.^[1] The highway has alternately (and unofficially) been known as part of the Pan-American Highway.^[2] In the part in the state of Oklahoma, the highway closely follows the old Chisholm Trail for cattle drives from Texas to railheads in Kansas in the 1860s and 1870s.

As of 2004, the highway's northern endpoint is just north of Pembina, North Dakota, at the Canadian border.

Its southern endpoint is in Fort Worth, Texas, at an intersection with I-35W and US 287. Between 1926 and 1991, US 81's southern endpoint was at the Mexican border in Laredo, Texas. In 1991, the endpoint was moved to San Antonio.

Route map:

• Endpoints of US 81