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Which Plumbing Certification Do You Need? Plumbing Licensing Guide

Which Plumbing Certification Do You Need? Plumbing Licensing Guide

Posted by Matt Krak

August 03, 2021

In the plumbing industry, understanding the ins and outs of your trade can set you apart from other technicians and give you a competitive edge while in the field. For many new job seekers, figuring out which certifications will offer the most bang for their buck may seem daunting.

To help give you the upper-hand while deciding on your plumbing journey, we’ve broken down the credentials that matter most for the top paying employers in the industry.


Most plumbers learn their trade through a four to five year apprenticeship program. Apprentices typically require a minimum of 2,000 hours of on-the-job training, as well as some technical instruction from an accredited technical college each year. Instruction tends to focus on safety, local plumbing codes and regulations, and learning how to read blueprints. Education also focuses on applied physics, chemistry, and mathematics. Typically you can find an accredited apprenticeship program through your local trade union, trade association, or plumbing business.

Licenses, Certifications, and Registrations

After completing an apprenticeship program, plumbing apprentices will need to pass a required licensing exam to become journey-level workers depending on the state they work in. Although licensing requirements vary, states and localities often require workers to have 2 to 5 years of experience and to pass an exam that shows their knowledge of the trade before allowing plumbers to work independently. To learn more about your state's licensing requirements, see Housecall Pro's Guide to Plumbing Licensing by State.

For this case, we'll breakdown the Plumbing (C-36) Licensing Exam for the state of California. The Plumbing (C-36) Examination is divided into five major sections:


Rough-in and Top Out Plumbing Systems covers underground installations, piping layout, piping installation, and fuel gas piping.

Planning and Estimating covers plan reading, bidding, pipe sizing, and water conservation.

Service, Repair, and Remodel Plumbing Systems covers troubleshooting plumbing, isolating leaks and damage, repairing plumbing, and retrofitting plumbing.

Safety covers job site safety, personnel safety, and public safety.

Finish Plumbing Installations covers plumbing fixtures, water heaters, shut-off valves, specialty installations, and industrial piping.

To prepare for licensing exams, review your state's most up to date Plumbing Code, and take a practice test prior to the exam.


After completing an apprenticeship and becoming licensed at the journey level, plumbers may advance to become a master plumber, supervisor, or project manager. Some plumbers choose to start their own business as an independent contractor, which may require additional licensing. 

To learn about other career opportunities once you receive your license, read Housecall Pro's Ultimate Guide to Becoming a Certified Plumber.