California State Route 99

State Route 99
SR 99 highlighted in red
Route information
Maintained by Caltrans
Length	424.85 mi[1] (683.73 km) (includes overlap with US 50 and I-5 in Sacramento)
Existed	1926 as US 99, 1964 as SR 99–present
Major junctions
South end	I-5 near Wheeler Ridge
Major intersections	SR 58 in Bakersfield SR 41 in Fresno SR 108 / SR 132 in Modesto SR 120 in Manteca SR 4 in Stockton US 50 / I-80 BL in Sacramento I-5 in Sacramento SR 70 near Nicolaus SR 20 in Yuba City SR 32 in Chico
North end	SR 36 near Red Bluff
Location
Country	United States
State	California
Counties	Kern, Tulare, Fresno, Madera, Merced, Stanislaus, San Joaquin, Sacramento, Sutter, Butte, Tehama
Highway system
State highways in California Interstate US State Scenic History Pre‑1964 Unconstructed Deleted Freeways
← US 99 → US 101

State Route 99 (SR 99) is a north–south state highway in the U.S. state of California, stretching almost the entire length of the Central Valley. From its southern end at Interstate 5 (I-5) near Wheeler Ridge to its northern end at SR 36 near Red Bluff, SR 99 goes through the densely populated eastern parts of the valley. Cities served include Bakersfield, Delano, Tulare, Visalia, Fresno, Madera, Merced, Turlock, Modesto, Manteca, Stockton, Sacramento, Yuba City, and Chico.

The highway is a remnant of the former Mexico to Canada U.S. Route 99 (US 99), which was decommissioned in 1972 after being functionally replaced by I-5 for long-distance traffic. The entire segment from Wheeler Ridge to Sacramento has been upgraded as of January 2016 to a freeway at least four lanes wide, and the California Department of Transportation (Caltrans) plans to further upgrade the segment to a minimum width of six lanes and also bring it into compliance with Interstate Highway standards as a parallel route to I-5 for Los Angeles–Sacramento traffic. North of Sacramento, the road ranges from a rural two-lane road to a four-lane freeway, with much of it following the route formerly designated as US 99E.