Official Sources and Standards
The free, official standards that govern traffic control signs in California — and how the national, state, and local layers fit together.
Traffic control standards are layered. Knowing which document applies — and in what order — keeps a California traffic control plan defensible. Each resource below is free and opens the official government or federal website.
Free official resources
- Federal MUTCD (FHWA)Federal
The national Manual on Uniform Traffic Control Devices, published by the Federal Highway Administration — the base standard all states build on.
Free official resource — opens official government website
- California MUTCD 2026 (Caltrans)California
California's adoption of the MUTCD with state-specific modifications. The CA MUTCD governs traffic control device use on California streets and highways.
Free official resource — opens official government website
- FHWA Standard Highway SignsFederal Publication
Federal sign design details — layouts, dimensions, and legends used to fabricate signs to the MUTCD standard.
Free official resource — opens official government website
- Caltrans Sign ChartsCalifornia
Caltrans sign charts catalog California sign codes and designs, including California-specific signs and sizing.
Free official resource — opens official government website
How the standards layer
- National — Federal MUTCD (FHWA). The base standard for traffic control devices across the United States.
- State — California MUTCD 2026 (Caltrans). California’s adoption of the MUTCD with state-specific modifications. This is the controlling standard for California streets and highways, effective January 18, 2026.
- State design — Caltrans sign charts, sign specifications, and Standard Plans. Define how California signs are coded, dimensioned, and fabricated.
- Local — city and county requirements. Agencies such as the City of Los Angeles (StreetsLA, Bureau of Engineering) and LA County DPW may add requirements beyond the CA MUTCD. For state highways in the LA region, Caltrans District 7 reviews encroachment permits.
When the layers differ, the more specific and more stringent requirement generally governs — but always confirm with the agency that has jurisdiction over the roadway.
Educational reference only. This is not an official Caltrans, FHWA, or local agency publication and is not legal or engineering advice. Always verify sign selection, size, placement, spacing, and application against the current CA MUTCD 2026, Caltrans sign specifications, Standard Plans, project documents, and the reviewing agency’s requirements.
Need help applying these standards?
Public Ready works within the CA MUTCD, Caltrans specifications, and local agency requirements every day and can help you build compliant traffic control plans and sign packages.