California Plumbing Workers Comp Rates (2026)
The published California pure premium for plumbing workers comp, class 5183(1) (Plumbing (employees whose regular hourly wage does not equal or exceed $35.00 per hour)), is $5.716 per $100 of payroll (effective September 1, 2026). California carriers currently charge about this level on average.
California carriers file their own rates. Rating bureau data shows the average charged rate running at about the level of the average advisory pure premium, so the figure is used as-is here. Your quote can be lower or higher. Source.
California class codes for plumbing
- 5183(1): Plumbing (employees whose regular hourly wage does not equal or exceed $35.00 per hour)
- 5187(1): Plumbing (employees whose regular hourly wage equals or exceeds $35.00 per hour)
California does not use NCCI: the WCIRB is an independent rating bureau with its own classification system and codes, and many construction trades are split into dual wage classes where each employee's payroll goes to a low-wage or high-wage code based on that employee's regular hourly wage.
Plumbing work involves back strain, cuts, burns from soldering and hot water, and work in crawl spaces and other confined spaces.
What comp costs per plumber in California
The Bureau of Labor Statistics counts 47,660 plumbers, pipefitters, and steamfitters on payrolls in California (May 2025), the 1st largest workforce among the 50 states and DC. The median wage is $35.01 an hour, 14% above the US median of $30.67.
Plumbers, pipefitters, and steamfitters make up about the same share of California jobs as they do nationally (location quotient 0.87).
At the published California pure premium of $5.72 per $100 of payroll for class 5183(1), which California carriers charge at about face value on average, comp on one worker at that wage costs about $2.00 for every hour worked, or $4,165 a year full time. A 2-person crew comes to roughly $8,331 a year in premium before any experience mod.
Because premium is charged on payroll, who you hire moves the bill. California pay runs from $22.76 an hour at the 10th percentile to $63.03 at the 90th, so the same rate costs $1.30 an hour on a new hire and $3.61 on a senior hand.
Workers comp requirements in California
- Coverage required: 1 employee
- Owners and sole proprietors: Owners excluded only by written waiver; licensed roofers must carry even with no employees
- State fund: Competitive state fund (State Compensation Insurance Fund)
- Waiting period: 3 days; waived if hospitalized or disability exceeds 14 days
- Penalty for going without: Misdemeanor; fine of at least $10,000, stop-work orders, and CSLB license suspension
California uses its own WCIRB rating bureau, and SB 216 will require every licensed contractor to carry coverage even with no employees (effective 2028; roofers already).
California vs neighboring states
- Oregon: about $1.46 per $100 of payroll
California has the highest plumbing comp rate in its region; every neighboring state charges less per $100 of payroll.
If your crews work across the line, list those states under item 3.A or 3.C of your policy before the job starts. Rates follow the state where the work is done, not where your office is.
What moves a plumbing comp bill
- Plumbing rates sit in the middle of the construction classes; the swing comes from your experience mod. Trench and excavation injuries are the costly claims, so trench-safety training pays back quickly.
- Some states split residential and commercial plumbing into different classes. If you do both, make sure the payroll for each is recorded so the cheaper work is not rated at the higher class.
- Apprentices carry the same class rate as journeymen, but their lower wages mean less premium per hour. Your payroll mix matters as much as the rate.
- Uninsured subs (excavators, drywall patchers) get added to your payroll at audit unless you collect certificates before they start.