Arizona plumbing license classes, side by side.

Scope is set by the Registrar of Contractors per class, and residential contracting is defined by the structure, not by the size of the job: houses, townhouses, condominiums, and what sits within residential property lines. Commercial contracting is anything else. A residential plumbing license covers residential work, a commercial license covers commercial work, and the dual CR-37 covers both on one license. We link the ROC table and we read it with you, but we do not interpret it for a specific job. The ROC License Department does that.

Under the current rules the ROC no longer accepts applications or issues new licenses in the R-37R subclassifications for gas piping, sewers and drains, swimming pool plumbing, solar liquid systems, central vacuum, and fixture refinishing. Licenses issued under those codes stay on the record, so an older license can still show one. The work itself now sits inside the R-37 plumbing scope, which the ROC says includes every R-37R subclassification. When your license carries a legacy code, we map it to the current scope on the submission so the underwriter reads the work, not the code.

Not what you must carry. Arizona requires the license bond for the license and workers’ comp with the first employee, whatever your plumbing class. What the class changes is the work we quote and the questions the underwriter asks. A commercial C-37 shop brings contract requirements, larger projects, and completed operations questions. A residential R-37 shop brings occupied homes and service calls. A dual CR-37 shop brings both, and the submission has to say how the revenue splits between them.

The ROC Contractor Search on roc.az.gov shows every licensed contractor’s classification, status, qualifying party, and bond, and it is the same record we pull before a quote. The ROC’s own guidance to consumers is to check that a contractor’s license class allows the work in the contract, so general contractors and property managers use the same lookup when they vet a bid. The sources on this page link to the ROC classification table and the consumer guidance where the search lives.

Not under the current classifications. The ROC lists gas piping inside the residential R-37 plumbing scope, which covers water and gas piping systems, and the commercial C-37 scope covers all plumbing within property lines. The separate R-37R Gas Piping subclassification is a legacy code that is no longer issued. What gas piping does change is the underwriting: carriers ask whether you run gas lines and how much of the work it is, because the claims look different. We state it on the submission rather than letting an audit find it.

R-37 is the residential plumbing class that includes solar, and the ROC says its scope includes every R-37R subclassification. R-37R Plumbing is the residential plumbing class without solar, and it is the residential half that the dual CR-37 license references. The other R-37R codes, such as gas piping or sewers and drains, are legacy subclassifications that the ROC no longer issues. For a coverage review the distinction matters only for solar work, which raises its own questions about roofs and equipment, and we ask about it directly.