It comprises about 9.4 miles (15.1 km) of the major north–south section line arterial Nellis Boulevard in the eastern Las Vegas Valley.

State Route 612 begins at the intersection of Nellis Boulevard and Tropicana Avenue (SR 593) on the border of unincorporated communities of Paradise and Whitney.

From there, the route heads north along Nellis Boulevard north as it travels through the Las Vegas area, entering the unincorporated town of Sunrise Manor and briefly forming the easternmost border of the city of Las Vegas.

[1][2] SR 612, as Nellis Boulevard, passes by many retail businesses as well as residential neighborhoods.

[3] SR 612 was established in the 1976 renumbering of Nevada's state highways.