Licensed Plumbing Contractor: What It Means
Hiring an unlicensed plumber is not a budget decision with a small downside. It determines whether the work can be permitted, whether your insurer treats a resulting claim as valid, and whether you have any recourse if something fails.
By Ramin Shahbaziasl, Owner, Eastside Repipe & Plumbing · Last updated October 10, 2025
Here is what the license actually covers in Washington, how it differs from certification and insurance, and how to check any company yourself in about a minute.
Licensed, Certified, and Insured Are Three Different Things
These get used interchangeably, including by companies that should know better. They are not the same, and in Washington two of the three are legally required.
Licensed refers to the business. Under RCW 18.106, a company must hold a plumbing contractor license to employ people doing plumbing work. That license comes with bonding and insurance requirements attached.
Certified refers to the individual. Washington issues plumber certificates of competency at journey level, residential service, and specialty levels. Earning one requires documented apprenticeship hours, a state examination, and continuing education to keep it current.
Both are mandatory. Contractor registration alone does not authorize plumbing work here, and the person performing it must hold a valid certificate. Someone working without one is not a cheaper option operating at a lower tier. They are working outside the law.
Insured is separate again. General liability covers damage caused to your property during the work. Workers' compensation covers the crew if someone is injured on site, and Washington administers it through the state fund, which makes it verifiable rather than a matter of trust.
Our companion guides cover what certification requires and what insurance actually protects you from in more detail.
How to Verify It Yourself
Do not rely on a badge on a website or a logo on a van. Washington maintains a free public lookup:
Enter the business name. It returns current registration status, bond, insurance, UBI number, expiration date, and any infractions or suspensions on record.
That is more informative than any credentials page, because it shows lapses. A license that expired last month leaves the badge on the website untouched.
Run it on us too, before you call. We would rather you did.
Why It Matters: Permits
This is the part homeowners underestimate.
Most substantial plumbing work is permitted, and only a licensed contractor can pull the permit. A permit means a jurisdiction inspector checks the work before walls close, which is your protection rather than a formality.
Unpermitted work does not usually cause a problem immediately. It causes a problem at resale, during a remodel, or when an insurer asks questions after a failure. That is a bad time to discover the water heater was replaced without one.
A contractor who suggests skipping the permit to save money is proposing that you carry the risk.
What Unlicensed Work Actually Costs You
No permit, so no inspection. Nobody independent has checked the work
Insurance complications. A claim arising from unpermitted or non-compliant work is a harder claim to make
No bond, so no recourse. An unlicensed contractor is also unbonded. If the work fails, you are pursuing an individual rather than making a claim
Liability for onsite injury. Without workers' compensation, an injury on your property becomes your problem
Problems at resale. Unpermitted plumbing surfaces during inspection and is negotiated against the sale price
The savings on the quote is real. So is everything above.
What Working With a Licensed Contractor Looks Like
Assessment. We inspect the system and find the cause rather than the symptom. On a repipe, that includes cutting a section and showing you the inside of your own pipe.
A written scope and quote. What is wrong, what the options are, and what each costs, itemized into labour, materials, permits, and restoration.
Permits pulled in our name. We handle the application and the inspection scheduling.
The work. Code-compliant materials and methods, with the property protected and the site left clean.
Testing and sign-off. Pressure testing before anything closes, then inspection.
A warranty in writing. Workmanship and materials, with a stated duration.
Where Credentials Matter Most
Some jobs are low stakes. These are not:
Repiping. Walls open, water off, permit pulled, inspection passed. Our repiping services page covers the process, and this is the job where license, bond, and insurance all matter at once.
Water heater replacement. Permitted in most jurisdictions, and involving either gas or a dedicated circuit.
Gas line work. Permitted, inspected, and unforgiving of mistakes.
Sewer and main line work. Slope, grading, and code compliance, mostly underground.
Anything inside a wall. Because the failure will not be visible until it has been running for a while.
What to Check Before You Hire
Run the L&I lookup on the business name. Confirm the license is active and the bond is in place
Ask for certificates of insurance and check the effective dates and coverage limits
Confirm who pulls the permit. It should be the contractor, in their own name
Ask about relevant experience. A whole-house repipe is a different job from a fixture swap
Get itemized written pricing, and ask how change orders are handled
Ask what the workmanship warranty covers, in years
Warning Signs
No license number offered, or reluctance to give one
Any suggestion that a permit is unnecessary
No written estimate
Cash only, or a large deposit before work begins
Refusal to provide proof of insurance
Pressure to decide immediately
The last one is worth weighing heavily. A failed water heater feels urgent, and urgency is what makes people skip every check above.
Frequently Asked Questions
What is the difference between a plumber and a licensed plumbing contractor?
The contractor license belongs to the business and allows it to employ plumbers, pull permits, and contract work. The individual plumber holds a certificate of competency. In Washington, both are required for legal plumbing work.
How do I know if my plumber is licensed?
Use the L&I lookup. Enter the business name, and it returns license status, bond, insurance, and any infractions. It takes about a minute, and it is free.
Is plumber certification optional in Washington?
No. Plumbing work must be performed by someone holding a journey level, specialty, residential service, temporary, or trainee certificate. It is a legal requirement rather than a voluntary credential.
Do licensed contractors charge more?
Sometimes, and the gap is usually smaller than expected. What the license buys is permitted work, an inspection, a bond, and insurance coverage. Our guide to judging plumbing value covers comparing quotes properly.
Why does insurance matter if they are licensed?
They cover different things. Licensing means the business is authorized to do the work. Insurance covers the situations where something goes wrong anyway, including property damage and on-site injury.
Do you handle whole-house repiping?
Yes, it is our main focus. We quote in writing, pull the permit in our own name, and pressure test before anything closes.
Check Us, Then Call Us
Run the L&I lookup on any plumber you are considering, us included. It costs nothing, and it tells you more than any page of credential claims.
When you are ready, request a free estimate or call 425-331-2011. We will assess the work, quote it in writing, and pull the permit in our own name.
We serve Bellevue, Kirkland, Redmond, Bothell, Renton, Issaquah, Sammamish, Seattle, and the wider Eastside service area.
