How to Compare Plumbing Contractor Insurance Quotes

The short version

Insurance quotes arrive as a stack of PDFs from different carriers, formatted differently, with different assumptions buried in different places, and a premium total on the last page. The temptation is to compare the totals. For a plumbing company that is the wrong comparison, for two reasons. First, the quotes are rarely for the same coverage: one may include completed operations and the other limit it, one may exclude work on multi-family projects, one may carry a $1,000 property damage deductible and another $5,000. Second, the largest line for most plumbing companies with employees, workers' compensation, is auditable: the premium you see is an estimate based on payroll and classifications, and the real premium is calculated after the policy year ends. A quote that looks cheaper because it assumed less payroll, or put plumbers in a cheaper classification, will be corrected at audit, with a bill.

The way to compare is to normalize first and price second. This article walks through what to line up, what to read, what to ask, and ends with a comparison table you can fill in.

A realistic scenario

This is a hypothetical. A plumbing contractor in Riverside County with eight field employees and three service vans receives three quotes for her general liability and workers' compensation renewal. The current carrier's renewal is up 12 percent. A second quote comes in 9 percent below expiring. A third, from a broker she has not used before, comes in 22 percent below.

She chooses the third. During the first week she asks for a certificate for a multi-family repipe and learns that the general liability policy carries an endorsement excluding residential projects over four units. She learns later that the workers' compensation quote assumed $320,000 in field payroll where her actual run rate is $470,000, and that the new broker, working from a verbal estimate, had placed six of her plumbers in the higher-wage, lower-rated classification when only two of them earn above the dual-wage threshold; at audit the carrier asks for time records to support the split and moves the other four. The audit bill arrives fourteen months after the policy started, for roughly what she had "saved," plus the cost of a separate policy she had to buy to cover the multi-family work.

The 22 percent was never real. The quote was for a smaller company doing different work.

Normalize before you price

The first pass has nothing to do with premium. Put every quote side by side and confirm the following match. Where they do not, ask the broker to requote on the same basis, or note the difference so you can price it.

Limits

General liability quotes for contractors are commonly structured as a per-occurrence limit, a general aggregate, and a separate products-completed operations aggregate. Confirm each is the same across quotes, and that the aggregate applies per project if your contracts require it. On workers' compensation, confirm the employers' liability limits (Part Two of the policy). On auto, confirm the combined single limit and whether hired and non-owned liability is included. On equipment, confirm the per-item and blanket limits.

Deductibles and retentions

A $5,000 property damage deductible on general liability is a meaningful difference from $500 for a trade whose liability claims so often involve water damage; see what happens when a plumbing repair causes property damage. Some quotes apply the deductible to defense costs as well as damages. On workers' compensation, a deductible plan changes the premium and your cash exposure. Read each one.

Completed operations

For a plumber, completed operations is where the expensive claims live: the fitting that fails after you leave. A standard commercial general liability form generally includes products-completed operations coverage, subject to the policy's terms, exclusions and endorsements, but a quote can remove or restrict it by endorsement, and some do for certain classes of work. Confirm it is included, unrestricted, and with the full aggregate. See completed operations coverage for plumbing contractors.

Exclusions and endorsements

The declarations page tells you the limits. The forms schedule tells you what the policy actually does. Ask for the list of endorsements on each quote and read for:

• Classification or operations limitations — residential, multi-family, new construction, tract work, work above a certain height or depth.
• Contractor-specific exclusions — subsidence, EIFS, mold and fungi, pollution (relevant to sewage), prior work, action-over (injury to employees who then sue the GC, who sues you), and any exclusion for damage to "your work."
• Subcontractor conditions — some policies exclude or surcharge work by uninsured subs, or require certificates and indemnity agreements as a condition of coverage.
• Additional insured capability — whether blanket additional insured (ongoing and completed), primary and non-contributory, and waiver of subrogation are included or available. If your customers require them, a policy that cannot provide them is not a comparable quote. See certificates of insurance and additional insured requirements.

Our article on plumbing contractor insurance exclusions you should understand goes through each in detail.

The workers' compensation quote: classifications and payroll

Workers' compensation premium in California is built from three inputs: the payroll estimated under each classification, the carrier's rate for that classification, and your experience modification. Two of the three are yours to check.

Class codes

Plumbing field payroll in California is assigned to a dual-wage classification pair, 5183 and 5187, split by the employee's regular hourly wage against a threshold set, and periodically adjusted, by the WCIRB. WCIRB's threshold rose from $32 to $35 per hour for policies effective on or after September 1, 2026, as part of the regulatory filing approved by the Insurance Commissioner for that date ($32 applies to policies effective September 1, 2024 through August 31, 2026); check that every quote uses the threshold in force for its effective date. Employees whose regular wage equals or exceeds the threshold go in the higher-wage, lower-rated code; everyone else goes in the lower-wage, higher-rated code. Office staff engaged exclusively in clerical work may belong in 8810, and outside salespeople in 8742, if their duties fit those classifications; WCIRB does not allow one worker's payroll to be divided between 8810 and another classification.

When comparing quotes, line up the class codes and the payroll under each. A quote that puts more payroll in the higher-wage code or in clerical than your records support will be reassigned at audit; the dual-wage rules require that the wage and hours be verifiable from payroll and time records, and undocumented payroll is assigned to the lower-wage classification. See workers' compensation payroll classifications for plumbing contractors.

A workers' compensation quote is only as accurate as the payroll and classifications behind it. The audit, not the quote, sets the premium.

Estimated payroll

Give every broker the same payroll projection, by classification, and check that each quote used it. A quote on lower payroll is not a lower rate; it is a deferred bill.

The X-Mod

Your experience modification is published by the WCIRB and applies regardless of carrier; it is calculated as actual losses divided by expected losses over the experience period. Every quote should show the same mod. If one does not, either the broker used an estimate or a revised mod was issued; ask. See what is an X-Mod and why does it matter.

Scheduled credits and debits

Carriers may apply underwriting credits or debits to the manual premium. A quote with a large credit is not wrong, but ask whether it is guaranteed for the term and what the carrier expects in return (safety program, claims history, payroll reporting). Credits are also the first thing to disappear at renewal.

Audit basis and terms

Workers' compensation premium is subject to audit; general liability for contractors is commonly auditable too, on payroll, revenue or subcontractor cost. Ask, for each quote:

• What is the rating basis (payroll, gross receipts, subcontractor cost)?
• How is the audit done (physical, phone, mail/online) and when?
• What happens if actual exposure is lower than estimated — is there a return premium, or a minimum premium that applies regardless?
• What is the minimum earned premium if you cancel midterm?
• How are uninsured subcontractors treated at audit?

A policy with a low deposit and a high minimum earned premium is priced differently from one that looks more expensive up front. See how to prepare for a workers' compensation premium audit.

Payment plans and financing

Compare the total cost of paying, not just the premium. Carriers offer different deposit percentages, installment counts and installment fees; some require premium financing through a third party at a finance charge. Pay-as-you-go workers' compensation, where premium is reported from each payroll run, can smooth cash flow and reduce audit surprises, if your payroll provider supports it. Put these in the comparison as a dollar figure.

What the price does not show

Carrier financial strength

AM Best and other rating agencies publish financial strength ratings for insurance companies. Many general contractors' insurance exhibits require your carriers to hold a minimum rating, and a quote from a carrier below that threshold can cost you work regardless of its price. Look up the rating for every carrier quoted.

Admitted versus non-admitted

An admitted carrier is licensed by the California Department of Insurance and subject to its solvency regulation, and the California Insurance Guarantee Association (CIGA) stands behind covered claims if an admitted property and casualty carrier becomes insolvent, within the limits the law sets. A non-admitted or surplus line carrier is not licensed by the Department and is placed through a licensed surplus line broker. The Department's commercial insurance guide notes that CIGA protection does not apply to surplus line insurers, and the disclosure notice California requires on surplus line placements says the state's guarantee funds will not pay claims if the insurer becomes insolvent. Surplus line policies also carry state taxes and fees; ask that they be shown on the quote. The Department maintains a List of Approved Surplus Line Insurers (LASLI), and the required surplus line notice suggests asking your broker whether the insurer is on it. For workers' compensation, CSLB accepts certificates only from insurers licensed to write workers' compensation in California. Non-admitted markets are legitimate and often the only option for an operation with claims or unusual work; the point is to know which you are buying and why.

Claims handling

Ask who adjusts claims (the carrier, a third-party administrator), how a claim is reported, and whether there is a 24-hour injury reporting line for workers' compensation. Check how settlement is handled: a standard commercial general liability form generally gives the carrier the right to investigate and settle claims at its discretion, without your consent, and consent to settle provisions (often paired with a "hammer" clause) are more common in professional liability forms than in contractors' general liability. For a contractor whose reputation depends on repeat GC work, how a water damage claim is handled matters as much as whether it is paid. On workers' compensation, claims handling affects the claim values that flow into your X-Mod for three years; a carrier that closes claims promptly and reports accurately is worth something. See how workers' compensation claims affect future insurance costs.

The broker's role

A broker's job in a quote comparison is to have described your operation accurately to every carrier, to have gotten quotes on the same basis, and to be able to explain every difference. A broker who sends over a lower number without explaining what it assumed has not done the comparison for you; you are doing it now. Ask each broker to walk you through their quote's assumptions, in writing.

A side-by-side comparison template

Fill one row per item, one column per quote. Leave premium for last.

When the rows above the premium line match, the premium comparison means something. When they do not, you now know what the difference is buying or giving up.

Practical takeaway

Start by sending every broker the same submission: the same payroll by classification, the same revenue, the same vehicle and equipment lists, the same description of operations including any gas, backflow, medical gas or multi-family work. Normalize the quotes on limits, deductibles, completed operations and endorsements before you look at price. Check the workers' compensation classifications and payroll against your own records. Ask about audit basis, minimum earned premium and payment terms, and look up each carrier's rating and admitted status. Then compare the total cost of paying, line by line, and decide.

The Riverside contractor in our scenario would have caught the multi-family exclusion in the forms schedule and the payroll gap in the workers' compensation line before binding, and would have seen that the "22 percent" quote was for a company that did not exist. If you want quotes built on an accurate description of your operation and presented on a comparable basis, start a quote; a licensed Pembroke producer reviews every submission before it goes to market.