Chain laws by state
When chains, traction devices or snow tires are required on mountain passes in California and Nevada. Each state links to its official rules and its passes.
California
Caltrans sets chain controls in three levels: R1, R2 and R3. The official wording of each level is below; the full explainer has a table for cars, SUVs and trailers.
Chains are required on all vehicles except passenger vehicles and light-duty trucks under 6,000 pounds gross weight and equipped with snow tires on at least two drive wheels.
Chains or traction devices are required on all vehicles except four-wheel/all-wheel drive vehicles with snow-tread tires on all four wheels.
Chains or traction devices are required on all vehicles, no exceptions.
Official sources: Caltrans: Chain Controls
Wording copied from the Caltrans chain controls page. Checked 2026-10-13.
California passes: Donner Pass · Echo Summit · Conway Summit · Deadman Summit · Sherwin Summit · Fredonyer Pass · Tejon Pass · Tehachapi Pass · Cajon Pass · San Gorgonio Pass · Pacheco Pass · California chain controls explained
Nevada
A chain or traction requirement applies when a highway is marked or posted with signs that require traction devices, tire chains or snow tires. It is unlawful to operate a motor vehicle on a posted highway under icy or snowy conditions without traction devices, tire chains or snow tires (NRS 484D.515).
On a posted highway, a motor vehicle or combination of vehicles with a gross weight or combined gross weight of 10,000 pounds or less must be equipped with traction devices, tire chains or snow tires. One with a gross weight or combined gross weight of more than 10,000 pounds must be equipped with tire chains (NRS 484D.520).
If a highway is marked or posted with signs requiring traction devices or tire chains on all motor vehicles except vehicles with 4-wheel drive and snow tires on all wheels, all such motor vehicles must be equipped with traction devices or tire chains (NRS 484D.520).
Official sources: Nevada Revised Statutes 484D.515 (Nevada Legislature) · Nevada Revised Statutes 484D.520 (Nevada Legislature) · NDOT: Safe winter driving
Nevada 511 shows active requirements as road conditions, for example "Chains Required". The pass pages on this site show those reports with the time they were made. Based on Nevada 511 road condition reports, not on the statute.
Summary of the statute text of NRS 484D.515 and 484D.520 (read on 2026-10-14 from a public copy of the Nevada Revised Statutes). The NDOT page is linked for current guidance; it could not be read when this page was written. Checked 2026-10-14.
Nevada passes: Mt Rose Summit · Spooner Summit · Daggett Pass · Emigrant Pass · Pequop Summit · Austin Summit
More states are coming as we add their cameras and passes.
This page is general information, not legal advice. Signs and officers on the road decide what applies to you. See current pass status.