California State Route 55

State Route 55
SR 55 highlighted in red
Route information
Maintained by Caltrans
Length	17.807 mi[1] (28.658 km)
Existed	1964–present
Major junctions
South end	Via Lido in Newport Beach
Major intersections	SR 1 in Newport Beach SR 73 in Costa Mesa I-405 in Costa Mesa I-5 in Tustin SR 22 in Orange
North end	SR 91 in Anaheim
Location
Country	United States
State	California
Counties	Orange
Highway system
State highways in California Interstate US State Scenic History Pre‑1964 Unconstructed Deleted Freeways
← SR 54 → SR 56

State Route 55 (SR 55) is an 18-mile (30-km) long north–south state highway that passes through suburban Orange County in the U.S. state of California. The portion of the route built to freeway standards is known as the Costa Mesa Freeway (formerly the Newport Freeway). SR 55 runs between Via Lido^[2] south of Pacific Coast Highway (SR 1) in Newport Beach and the Riverside Freeway (SR 91) in Anaheim to the north, intersecting other major Orange County freeways such as SR 22, SR 73, and Interstate 405 (I-405).

SR 55 was first added to the state highway system in 1931, known as part of Legislative Route 43, and was routed on surface streets. It was renumbered SR 55 in 1959, and the construction of the freeway portion began in the 1960s and continued until 1992. Due to congestion, several alternatives are being discussed to expand the freeway portion past its current end in Newport Beach. SR 55 received the first carpool lane in Orange County in 1985, and the first direct carpool ramp in 1995.