State Highway 99, abbreviated SH-99, is a north–south state highway through central Oklahoma.
It runs from the Texas border at Lake Texoma to the Kansas border near Lake Hulah.
It is 241.5 miles (388.7 km) long.
The highway overlaps US-377 for over half its length.

SH-99 continues as K-99 after crossing the border into Kansas.
This road continues for 233 miles (375 km) to the Nebraska border, where it becomes Nebraska Highway 99, which lasts an additional 14 miles (23 km).
Thus, SH-99 is part of a triple-state highway numbered "99", which lasts a total of 488 miles (785 km).

State Highway 99 began as State Highway 48, a short highway connecting Ada to Holdenville.
This highway was gradually expanded until it became a border-to-border route.
In 1938, it was renumbered to match K-99, which was renumbered from K-11 the same day.
State Highway 99, abbreviated SH-99, is a north–south state highway through central Oklahoma. It runs from the Texas border at Lake Texoma to the Kansas border near Lake Hulah. It is 241.5 miles (388.7 km) long. The highway overlaps US-377 for over half its length.
SH-99 continues as K-99 after crossing the border into Kansas. This road continues for 233 miles (375 km) to the Nebraska border, where it becomes Nebraska Highway 99, which lasts an additional 14 miles (23 km). Thus, SH-99 is part of a triple-state highway numbered "99", which lasts a total of 488 miles (785 km).
State Highway 99 began as State Highway 48, a short highway connecting Ada to Holdenville. This highway was gradually expanded until it became a border-to-border route. In 1938, it was renumbered to match K-99, which was renumbered from K-11 the same day.
Oklahoma State Highway 99