| State: | OK |
| Type: | US-Alt |
| Route: | 75 |
| Map Custom: | yes |
| Map Notes: | US-75 Alt. highlighted in red |
| Maint: | ODOT |
| Length Mi: | 30.15 |
| Established: | August 28, 1959 |
| Length Ref: | [1] [2] |
| Direction A: | South |
| Terminus A: | east of Beggs |
| Direction B: | North |
| Terminus B: | in Sapulpa (concurrent with SH-66) |
U.S. 75 Alternate (also signed as U.S. Highway 75A or State Highway 75A) is a 30.15miles highway near Tulsa. The southern terminus is at U.S. Highway 75 and SH-16 east of Beggs. The northern terminus is signed at State Highway 66 and State Highway 97 in Sapulpa. However, the highway continues unsigned along SH-66, ending at the north terminus of the Turner Turnpike, where SH-66 merges onto the free portion of I-44. It runs parallel to US-75 for its entire length.
Except for the segment between new US-75 and Beggs, US-75 ALT follows the route of the old US-75 prior to the construction of the Okmulgee Beeline and that road's subsequent designation as US-75 in 1959.
US-75 Alternate begins where SH-16 crosses under US-75 east of Beggs. West of this intersection, US-75 ALT is signed along with SH-16. The two highways continue west into the city of Beggs, where the partnership ends. US-75 ALT turns north onto the route of the old US-75, passing through Beggs and then rural areas of Okmulgee County on a due north course. The highway crosses into Creek County, then curves to the northeast for about 1miles before returning to a northerly course through Mounds.[3] After passing through Mounds, US-75 ALT follows a route a few degrees west of due north, bringing it to the town of Kiefer, where it serves as the western terminus of SH-67.
From Kiefer, the highway turns northwest. The highway bridges Polecat Creek as it turns west to enter the city of Sapulpa.[3] The route then turns back to the north as it gets closer the city's core. The highway intersects SH-117 in about the center of town. The road then intersects SH-33 and SH-66, while the mainline becomes SH-97. At this intersection, signage indicating the north end of US-75 ALT is posted.
Officially, however, US-75 ALT continues onward from here, turning right and following SH-66 through the east part of Sapulpa. This section of US-75 ALT is signed exclusively as SH-66. The road parallels I-44, the Turner Turnpike. The highways pass under the Creek Turnpike as well. Finally, as the Turner Turnpike comes to an end and I-44 transitions into a free Interstate, SH-66 merges onto the freeway. US-75 ALT ends at this point, just south of the Creek–Tulsa County line.
US-75 ALT largely follows the route of the old US-75 before the "Okmulgee Beeline", the expressway/freeway between Okmulgee and Tulsa, was built. On August 28, 1959, the US-75 name was moved onto the new highway, and US-75 ALT was designated for the old highway. The old route of US-75 south of Beggs continues to be designated as Old Highway 75 into Okmulgee, at which point it is signed as North Oklahoma Avenue until 6th Street.