California truck chain law
No calendar carry rule. When chain controls are posted, every heavy-duty vehicle over 6,500 lb must mount chains, snow tires or not, and Caltrans may turn back trucks without chains at screening points.
| Type | Chain up when posted |
|---|---|
| Carry season / effective dates | None. Caltrans: "California does not have any specific dates when vehicles are required to carry chains." |
| Who must carry chains | No statewide carry date. In practice any truck entering a chain control area must have chains; vehicles without them are turned back, and at truck screening check points heavy trucks must show the required chains to proceed. |
| When you must chain up | When the road is posted with a chains-required sign, all heavy-duty vehicles over 6,500 lb gross must have chains mounted on the drive axle (snow tires are no exemption). Braked trailers need at least one axle chained. Caltrans may require inside duals in severe conditions. |
| Where | Most often I-5 north of Redding, I-80 over Donner Pass, US 50 over Echo Summit; sometimes SR 58 near Tehachapi, I-15 Cajon Pass and I-5 Tejon Pass (Caltrans). |
| Penalty | Not stated in the official sources we checked. Confirm with the state. |
| Law | California Vehicle Code §605 and §§27450–27503 |
Official sources
Checked 2026-10-29. Chain controls are set live by the state, so follow posted signs and officers. Not legal advice.
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