# California Chain Controls Explained: R1, R2, R3 and Winter Tires

California chain controls have three levels. R-1: chains or traction devices are required on the drive axle, but vehicles with snow tires (at least 6/32 inch of tread) and four- or all-wheel-drive vehicles are exempt. R-2: chains are required on all vehicles except four- or all-wheel-drive vehicles with snow tires on all four wheels. R-3: chains are required on all vehicles with no exceptions. Every vehicle must carry chains in a chain control area.

## Chain control levels

| Level | Requirement | Exempt |
| --- | --- | --- |
| R-1 | Chains, traction devices or snow tires on the drive axle | 4WD/AWD vehicles; vehicles with snow tires on the drive axle |
| R-2 | Chains or traction devices on all vehicles | 4WD/AWD with snow tires on all four wheels (must still carry chains) |
| R-3 | Chains on all vehicles | None. Roads are often closed at this point |

## Before a mountain trip

- Check tread depth: at least 6/32 inch to count as snow tires ([how to measure](https://appointauto.com/guides/when-to-replace-tires-tread-depth/)).
- Buy chains that match your exact tire size, and practice fitting them at home.
- Check your owner's manual: some cars with low-profile tires allow only certain cable chains or textile socks.
- Set tire pressures cold to the door placard value; pressure drops in mountain cold ([why](https://appointauto.com/guides/tire-pressure-tpms-light/)).

Source: Caltrans. Check current conditions on [Caltrans QuickMap](https://quickmap.dot.ca.gov/).

## Find a tire shop

- [Tire shops in Los Angeles](https://appointauto.com/tire-shops/los-angeles/) — 1 listing
- [Tire shops in Oakland](https://appointauto.com/tire-shops/oakland/) — 1 listing
- [Tire shops in San Francisco](https://appointauto.com/tire-shops/san-francisco/) — 1 listing
- [Tire shops in San Jose](https://appointauto.com/tire-shops/san-jose/) — 1 listing
- [Tire shops in Santa Clara](https://appointauto.com/tire-shops/santa-clara/) — 1 listing
- [Tire shops in Sunnyvale](https://appointauto.com/tire-shops/sunnyvale/) — 1 listing

## Frequently asked questions

### Do I need chains if I have AWD in California?

At R-1 and R-2, a four-wheel or all-wheel-drive vehicle with snow tires on all four wheels can usually proceed without chains, but it must still carry chains in the chain control area. At R-3, everyone needs chains.

### What counts as a snow tire for chain controls?

A tire marked M+S (mud and snow) or with the three-peak mountain snowflake symbol, with at least 6/32 inch of tread.

### How fast can I drive with chains on?

Chain control areas have posted limits, typically 25 or 30 mph.

### Where can I check chain controls before I leave?

Caltrans QuickMap and the Caltrans road conditions line at 1-800-427-7623 show current chain controls.

## Related guides

- [When to Replace Tires: Tread Depth, the Penny Test and California Law](https://appointauto.com/guides/when-to-replace-tires-tread-depth/) — California's legal minimum is 1/32 inch, but wet grip fades long before. The penny and quarter tests, wear bars and other reasons to replace.
- [How to Read a Tire Size: What 225/65R17 98H Means](https://appointauto.com/guides/how-to-read-tire-size/) — A plain guide to the numbers on your tire sidewall: width, aspect ratio, construction, rim diameter, load index, speed rating, DOT code and the UTQG rating.
- [Tire Pressure Light On? What the TPMS Warning Means and What to Do](https://appointauto.com/guides/tire-pressure-tpms-light/) — A steady TPMS light means a tire is low; a flashing one means a system fault. How to check pressure, find the right psi and handle cold mornings.

[Find a shop near you](https://appointauto.com/)

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Source: https://appointauto.com/guides/california-chain-controls-winter-tires/ · Last updated 2026-10-23. Station details are compiled from public listings and can change; call the shop to confirm hours and prices before you go.