Construction Zone Traffic Control Contractor Insurance in California (C-31)

What the C-31 license covers

The CSLB’s definition

“A construction zone traffic control contractor prepares or removes lane closures, flagging, or traffic diversions, utilizing portable devices, such as cones, delineators, barricades, sign stands, flashing beacons, flashing arrow trailers, and changeable message signs, on roadways, including, but not limited to, public streets, highways, or any public conveyance.”

Work-zone claims are some of the most expensive in construction: a flagger struck by a vehicle, or a driver who crashes and claims the signs, cones or arrow board were placed wrong. Those liability claims often name every contractor on the job. Public agencies and prime contractors require high limits, additional insured status and waiver of subrogation, and your trucks and arrow boards need their own coverage.

The C-31 coverage stack

General Liability — for claims by drivers that blame the lane closure or signage
Workers’ Compensation — code confirmed with the carrier before you bind
Commercial Auto — trucks, attenuator trucks and towed arrow boards
Inland Marine — message signs, arrow boards, cones and barricades
CSLB license bond — the $25,000 bond every C-31 license needs
Excess & Umbrella — highway and public contracts often require $5M or more

C-31 requirements

What California requires of a C-31 licensee

Requirement	What applies to C-31 traffic control contractors
Contractor’s license bond	A $25,000 bond is required to activate and keep the license. LLC licensees also need a $100,000 LLC employee/worker bond. How the bond works
Workers’ compensation	Required now if you have even one employee. With no employees you can file a CSLB exemption, but that option ends for every classification on January 1, 2028. Check your requirement
General liability	Required by the CSLB only for LLC licensees (at least $1 million). General contractors and owners require it anyway, usually with additional insured status.

Workers’ comp class code and 2026 rate

Class code	Description	Advisory rate per $100 payroll
—	No single WCIRB code covers flagging and lane closures. The class is assigned based on what your crews actually do and who they work for.	Varies

Source: WCIRB California, approved September 1, 2026 advisory pure premium rates and classification descriptions. These are benchmark loss costs, not quotes: each carrier files its own rates, and your experience mod and credits adjust the final premium.

California’s workers’ comp classification system has no code written specifically for traffic control or flagging, so carriers assign one based on your operations. That makes it worth confirming before you bind: a misclassified policy can come back with a large bill at audit. We confirm the code with the carrier before quoting.

No single code

workers’ comp class is set by your operations

Driver claims

the biggest liability exposure for lane closures

WC by 2028

every C-31 needs a policy, employees or not

Common questions

C-31 coverage, answered

What is the workers’ comp class code for traffic control in California?

There is no WCIRB class written specifically for flagging or construction zone traffic control. The code is assigned based on your operations and can differ between carriers, which is why we confirm it before you bind a policy.

Is general liability required for a C-31 license?

Only for LLC licensees, which must carry at least $1 million. Sole proprietors and corporations aren’t required to by the CSLB, but most general contractors and public agencies will require it before you start.

Does my general liability cover a driver who crashes in my lane closure?

If the driver claims your setup caused the crash, general liability is the policy that responds, as long as the policy was in force and no exclusion applies. Damage to your own trucks and equipment needs commercial auto and inland marine coverage.

Do traffic control contractors need workers’ comp with no employees?

Not yet. A C-31 licensee with no employees can file the CSLB exemption until January 1, 2028, when the exemption ends for every classification. Any employee means you need a policy now.

Construction Zone Traffic Control Contractor Insurance in California

The CSLB’s definition

The C-31 coverage stack

What California requires of a C-31 licensee

Workers’ comp class code and 2026 rate

C-31 coverage, answered

Get a C-31 quote that fits the work