Hiring Licensed Plumbers: What Contractors Need to Know
Hiring a licensed plumber — whether as an employee or a subcontractor — requires careful verification of credentials. Plumbing work affects the safety of building occupants through water supply, drainage, gas piping, and fire suppression systems. Most jurisdictions require plumbers to hold specific licenses that demonstrate competency in plumbing codes, safety practices, and installation methods. Failing to verify a plumber's license exposes your organization to serious liability, code violations, and potential health hazards.
This guide covers what employers and contractors need to verify when hiring plumbers, how to check credentials, and what to watch for throughout the process.
Plumber Licensing Info
See our plumber licensing guide for state-by-state requirements, or use the verification directory to look up a plumber's license directly.
What Licenses to Verify
Plumber licensing has multiple tiers, and the specific license needed depends on the work being performed and the jurisdiction:
- Apprentice plumber. An apprentice is in training and must work under the direct supervision of a licensed journeyman or master plumber. Apprentices typically hold a registration or trainee card rather than a full license.
- Journeyman plumber. A journeyman has completed the required apprenticeship and examination and can perform plumbing work independently. However, journeymen may not be able to pull permits or supervise others in all jurisdictions.
- Master plumber. A master plumber holds the highest individual license level and can typically pull permits, supervise other plumbers, and take full responsibility for plumbing projects.
- Plumbing contractor license. In many states, the business entity performing plumbing work must hold a separate contractor license, which may require a designated master plumber and proof of insurance and bonding.
- Specialty licenses. Some jurisdictions issue separate licenses for specific plumbing work such as gas fitting, medical gas piping, fire sprinkler installation, or backflow prevention device testing. Verify that the plumber's license covers the specific type of work to be performed.
How to Verify a Plumber's License
The verification process for plumbers follows these steps:
- Ask for the license number and issuing jurisdiction. Request the plumber's license number, the state or local jurisdiction that issued it, and the license type (journeyman, master, contractor, etc.).
- Identify the correct licensing authority. Plumber licenses may be issued at the state level, the county level, or the city level depending on the jurisdiction. Some states have statewide licensing; others leave it to local authorities. Use our verification directory to find the right starting point.
- Search the online database. Most licensing authorities provide an online lookup tool where you can search by name or license number. Confirm the license type, status (active), and expiration date.
- Verify insurance and bonding. Many states require licensed plumbers to maintain liability insurance and a surety bond. Ask for certificates of insurance and bond documentation and verify they are current.
- Check for code violations or disciplinary actions. Review the licensing board's records for any history of code violations, complaints, or disciplinary actions against the plumber.
- Confirm permit-pulling authority. If the project requires plumbing permits, verify that the plumber (or their employing contractor) has the authority to pull permits in the jurisdiction where the work will be performed.
Red Flags to Watch For
These warning signs should prompt further investigation when hiring a plumber:
- No license or unwillingness to provide a license number. Any legitimate plumber will readily provide their license information. Reluctance is a major red flag.
- License type does not match the work. A journeyman plumber may not be authorized to pull permits or take on projects that require a master plumber. An apprentice cannot work unsupervised.
- License is from a different jurisdiction. A plumber licensed in a neighboring city or state may not be authorized to work in your jurisdiction. Verify local requirements.
- Expired license or lapsed insurance. An expired license means the plumber is not currently authorized to perform plumbing work. Lapsed insurance or bonding leaves you exposed to financial risk.
- History of code violations or failed inspections. While a single minor issue may not be disqualifying, a pattern of code violations or failed plumbing inspections suggests quality or competency problems.
- Offering to work without permits. A plumber who suggests skipping the permit process is a serious concern. Unpermitted plumbing work can lead to health hazards, code violations, insurance problems, and issues when selling the property.
Ongoing Compliance
For employers who hire plumbers as W-2 employees (rather than subcontractors), ongoing license management is critical:
- Track license renewal dates. Plumber licenses typically renew every one to three years. Set reminders and re-verify through the licensing authority after each renewal.
- Monitor continuing education compliance. Many states require plumbers to complete continuing education hours on code updates (particularly when new editions of the plumbing code are adopted) as a condition of renewal.
- Maintain insurance and bond certificates on file. If you hire plumbing subcontractors, keep current certificates of insurance and bond documentation on file and verify them at each renewal.
- Track apprentice-to-journeyman progression. If you employ apprentice plumbers, monitor their progress toward journeyman licensing and adjust supervision levels accordingly.
- Stay current on code adoption. Different states and jurisdictions adopt different editions of the plumbing code on different timelines. Ensure your plumbers are current on the code version enforced in each jurisdiction where they work.
State-Specific Considerations
Plumber licensing varies significantly across states and even within states:
- Some states have statewide plumber licensing administered by a single board. Others have no state-level plumber license and leave licensing entirely to cities and counties.
- License categories vary — some states use a journeyman/master structure, while others add categories such as residential plumber or maintenance plumber with more limited scopes of work.
- Bonding requirements differ significantly by state. Some states require surety bonds ranging from a few thousand dollars to $25,000 or more, while others do not require bonding at all.
- There is no national plumber license compact, so each state or local license is independent. Some states have limited reciprocity agreements, but plumbers generally need to apply in each state where they intend to work.
For detailed state-by-state plumber licensing requirements, visit our plumber licensing guide.
Frequently Asked Questions
What is the difference between a journeyman plumber and a master plumber?
A journeyman plumber has completed an apprenticeship (typically four to five years of on-the-job training plus classroom instruction) and passed a journeyman examination. A journeyman can perform plumbing work independently but may not be able to pull permits or supervise other plumbers in all jurisdictions. A master plumber has additional experience beyond the journeyman level (usually two to four more years) and has passed a more comprehensive exam. Master plumbers can typically pull permits, supervise journeymen and apprentices, and run a plumbing business. The specific requirements for each level vary by state and local jurisdiction.
Can a plumber licensed in one state work in another state?
Generally, no. There is no national plumbing license, and most states require plumbers to hold a license issued by that state or by the local jurisdiction where the work will be performed. Some states have reciprocity agreements with specific neighboring states that may streamline the licensing process, but the plumber typically still needs to apply for and receive a license in the new state. Additionally, some local jurisdictions require separate local licenses or registrations beyond the state license. Always verify that a plumber holds the appropriate license for the specific jurisdiction where the work will be performed.
Who is responsible for pulling plumbing permits — the employer or the plumber?
Permit requirements vary by jurisdiction, but in most areas, the licensed plumbing contractor or master plumber is responsible for pulling permits before plumbing work begins. The permit is typically pulled by the company or contractor rather than the individual journeyman performing the work. The licensed individual or company whose name appears on the permit is generally responsible for ensuring the work meets code and passes inspection. Employers should confirm that permits are properly obtained before work begins and that the licensed individual is appropriately involved in the project.
What insurance and bonding should an employer verify when hiring a plumber?
At minimum, verify that the plumber or their employing company carries general liability insurance and workers' compensation insurance (where required by state law). Many states require licensed plumbers to maintain a surety bond as a condition of licensure — the bond amount varies by state and license type. If you are hiring an independent plumbing contractor (rather than an employee), request certificates of insurance and verify they are current. Typical general liability coverage ranges from $500,000 to $2 million. Do not rely on verbal assurances; request and verify actual certificates directly with the insurer if possible.
What plumbing codes should employers be aware of?
Most jurisdictions in the United States adopt some version of a model plumbing code, though the specific edition and any local amendments vary. The most commonly adopted codes include the International Plumbing Code (IPC) and the Uniform Plumbing Code (UPC). Some jurisdictions adopt these codes with modifications, and a few have developed their own plumbing codes. The plumber you hire should be current on the code version enforced in your jurisdiction. Code compliance is verified through the permit and inspection process — another reason why pulling permits before work begins is essential.
Disclaimer: This article provides general guidance for employers hiring licensed plumbers. It does not constitute legal advice. Plumber licensing requirements, permit processes, bonding requirements, and employer obligations vary by state and local jurisdiction. Consult with qualified HR professionals or legal counsel for advice specific to your situation.
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