Texas State Highway 45

State Highway 45
Route information
Length	25.024 mi[1] (40.272 km)
Existed	1985–present
Major junctions
Beltway around Austin
Southwestern segment
CCW end	FM 1626 in Austin
Major intersections	Loop 1
CW end	RM 1826 in Austin
Eastern segment
CCW end	RM 620 in Austin
Major intersections	US 183 Loop 1 Toll I-35 SH 130 Toll US 290 SH 71 US 183 SH 130 Toll
CW end	I-35 in Austin
Location
Country	United States
State	Texas
Highway system
Highways in Texas Interstate US State Toll Loops Spurs FM/RM Park Rec
← I-45 → SH 46

State Highway 45 is a freeway loop around Austin, Texas, that exists in two open segments. The official designation of SH 45 is such to form a complete loop around Austin, a distance of roughly 80 miles (130 km).

One segment is in southwest Austin and runs southeast from Ranch to Market Road 1826 to Farm to Market Road 1626 and intersects the southern terminus of Loop 1 (Mopac Expressway). Between RM 1826 and Loop 1, the roadway is a divided four-lane facility with a wide median intended to accommodate a future freeway, after which the current lanes would serve as frontage roads. Between Loop 1 and FM 1626, the roadway becomes a tolled freeway.

The other segment is a toll road that forms a backwards C-shape along the boundary of Travis and Williamson County before bending down along the eastern edge of the Austin metropolitan area where it shares its route with SH-130.