State Route 58 between Santa Margarita and Buttonwillow is a winding mountain road through a thinly populated area.

However, this section of SR 58 does pass through the Carrizo Plain, which is known for its scenic beauty and geological features, including the San Andreas Fault.

SR 58 then takes another winding road before joining with State Route 33 in the small town of McKittrick.

SR 58 then proceeds northeast for several miles before changing to an east-west alignment and reaching Buttonwillow.

SR 58 then joins with the north-south Interstate 5 (I-5) for a few miles to Stockdale Highway, where it resumes heading east and intersects with State Route 43 before reaching Bakersfield.

Approximately 10 miles (16 km) east of an interchange with U.S. Route 395, SR 58 resumes expressway status with two lanes in each direction until just before reaching the easternmost terminus at Interstate 15 in Barstow.

With the lack of four-lane or greater, divided highways that cross the Sierra Nevada between SR 58 at the Tehachapi Pass and Interstate 80 at Donner Summit about hundreds of miles to the north, I-5 and SR 58 are used by motorists to travel between Northern California and points to the southeast, such as Las Vegas (via I-15) and Interstate 40, without having to face the extreme traffic congestion of greater Los Angeles.

Freeway bypasses in Tehachapi, Boron, Mojave, Hinkley, and Kramer Junction were completed in c. 1975, 1981, 2003, 2017, and 2020, respectively.

Although construction was controversial since it displaced dozens of homes and businesses,[10] by September 2017, all but a few buildings in the path had been demolished.

[11] On February 5, 2021, the city transferred the Westside Parkway to Caltrans and California Highway Patrol jurisdiction.

[12] City officials then announced in October 2022 that the project was nearly complete, and that they were working on the last 800 feet of the connection, specifically, the northbound SR 99 to westbound SR 58 transition ramp, with an estimated 8 months of construction left.

[13] Meanwhile, Caltrans began installing signage rerouting SR 58 traffic from I-5 onto Stockdale Highway and the Westside Parkway east to at least Mohawk Street.

[22] Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage.