SR 425 begins at the intersection of Third Street, Gold Ranch Road, and a state maintained frontage road in Verdi, near the West Verdi interchange (Exit 2) with Interstate 80.

From the highway's western terminus, I-80 Business follows Gold Ranch Road an additional 0.939 miles (1.511 km) south to end at an I-80 westbound onramp.

The highway originally carried State Route 1 and later U.S. Route 40[1] on its trek west from Reno over Donner Pass towards Sacramento, California.

As Interstate 80 was being completed in the 1960s, it was largely replacing US 40 throughout the western United States.

The entire route is in Verdi, Washoe County.