Quick Reference Table
Requirement | Details |
|---|---|
License Type | Licensed Plumbing Contractor |
Regulating Agency | Washington State Department of Labor & Industries (L&I) |
Experience Required | No specific experience required for contractor; designated plumber must be L&I certified |
Exam Required | No exam required for contractor license |
Renewal Cycle | 24 months from the date of issuance |
Continuing Education | Not required for contractor license |
Fees | License issuance/renewal: $139.10 (as of Nov 2026, WAC fee schedule) |
Apply | |
Official Board URL | |
License Lookup | |
Application Form |
Who Needs a License in Washington?
Anyone advertising, bidding, or actually performing plumbing work in Washington must hold a licensed plumbing contractor credential issued by L&I. There are no minimum contract value thresholds or clear handyman exemptions described on the official L&I pages. All plumbing tasks require you to meet the full plumbing license requirements in Washington.
If your business is installing, repairing, or maintaining plumbing systems in Washington, you must hold the plumbing contractor license. There are no separate rules for residential versus commercial projects. General contractors, by default, cannot perform any plumbing work unless they also acquire a plumbing contractor license. Subcontractors who wish to do plumbing must be properly licensed as well. There is no owner-builder or handyman exception officially listed: all individuals or companies providing plumbing labor or services must comply with the state’s plumbing license requirements in Washington. See L&I for exact statutory notes if you are uncertain about your scope.
Plumbing License Types
Washington offers only one contractor license classification for this trade: the Licensed Plumbing Contractor, as required by Chapter 18.106 RCW and enforced by L&I. There are no tiered or specialty contractor classifications specific to plumbing as of July 1, 2021; the old "specialty plumbing contractor" category is no longer valid.
With the Licensed Plumbing Contractor credential, you can advertise, bid, offer to perform, and complete any plumbing work permitted by law in Washington. If your business operates with a broader scope, you may also register as a general or specialty contractor for non-plumbing trades. However, you must meet the separate plumbing license requirements in Washington to perform or subcontract any plumbing work. A designated plumber (a person with a valid, L&I-issued plumber certification) must be assigned to your company for your license to remain valid. This enables enforcement of state plumbing standards at the business level and helps prevent unlicensed plumbing activities.
Plumbing License Requirements in Washington: How to Get Licensed
The process for obtaining a plumbing contractor license in Washington includes several detailed steps. Every applicant must start with business registration, then complete bonding and insurance, designate a certified plumber, fill out required forms, and submit the application to L&I for review and approval. Follow the plumbing license requirements in Washington closely to get approval.
Step-by-Step Licensing Procedure
Register Your Business: Register your business entity with the Washington State Department of Revenue. Corporations, LLCs, or partnerships also file with the Secretary of State before they can apply as a contractor.
Obtain Bond: Purchase a $6,000 Continuous Plumbing Contractor Surety Bond or complete an Assignment of Savings Account. The bond must meet exact L&I standards for your application to be accepted (verify specifications).
Secure General Liability Insurance: Acquire general liability insurance coverage for at least $250,000 combined single limit, or split limits of $200,000 public liability and $50,000 property damage. List L&I as the certificate holder on the insurance policy.
Assign a Designated Plumber: Choose a Designated Plumber who holds an active journey-level (or medical gas) plumber certificate with L&I. Complete and notarize form F627‑052‑000 to assign this individual to your business.
Complete Application Forms: Fill out and notarize the Application for Plumbing Contractor License (form F627‑051‑000) and the Designated Plumber Assignment form (F627‑052‑000).
Pay Required Fees: Pay the applicable fees: license/application fee of $139.10 (as of Nov 2026), plus a $50 fee for Designated Plumber assignment. Confirm latest amounts using the official fee schedule.
Submit Documents by Mail: Mail your completed, notarized forms, proof of bond, proof of insurance, Designated Plumber assignment, and payment to: Plumbing Certification, PO BOX 44470, Olympia, WA 98504‑4470.
Wait for Processing and Approval: Allow 1 to 2 weeks after receipt for review and processing. If your forms and documentation are accepted, L&I will mail your license card in approximately two weeks. Do not perform plumbing work until your license is formally approved and active.
Processing Times and Online Application
Currently, all first-time plumbing contractor applications in Washington must be submitted by mail. L&I estimates processing completion within 1 to 2 weeks after they receive all required materials. You may only start contracting as a licensed plumbing contractor after you receive your active license notice by mail or confirm your company is shown as Active in L&I’s license lookup tool. Carefully completing every part of the plumbing license requirements in Washington will speed up processing.
Application Requirements
You must meet several specific requirements to obtain a plumbing contractor license in Washington. L&I mainly checks business registration, bond and insurance documentation, and the legal assignment of a qualified Designated Plumber to your company. These are central plumbing license requirements in Washington.
Experience and Age
There is no minimum age or experience requirement for the plumbing contractor license itself. You do not need to submit experience logs or proof of technical plumbing knowledge for the contractor credential. However, your assigned Designated Plumber must hold an active, L&I-issued journey-level or medical gas plumber certificate.
Bond and Insurance
Every plumbing contractor applicant must provide:
Bond: $6,000 continuous surety bond, or an Assignment of Savings Account for the same amount. This bond protects consumers if you fail to comply with licensing rules or contractual obligations.
General Liability Insurance: A minimum of $250,000 combined single limit (or split as $200,000 public liability plus $50,000 property damage). L&I must be listed as the certificate holder.
Background Check and Federal Certifications
L&I does not require a criminal background check or fingerprints for the plumbing contractor license. There is also no reference to needing EPA, Department of Energy, or other federal certifications as a state licensing prerequisite. Only the Designated Plumber assignment must be validated with L&I records for the technical certification. Applicants must focus on meeting the plumbing license requirements in Washington for a successful outcome.
Exams
You do not need to pass any trade, law, or business exam to become a licensed plumbing contractor in Washington. There are no exam fees or testing steps for the contractor license application. Meeting all other plumbing license requirements in Washington is sufficient.
If you or your employees want to become a Designated Plumber, then an exam is required for that individual plumber certification. However, this is a separate process from the plumbing contractor licensing and is covered by plumber certification rules, not contractor licensing.
Fees
You must pay all state-mandated licensing and processing fees to hold an active plumbing contractor license in Washington. Below is a detailed schedule of the most current fees as verified on state government sites. Confirm all current fee amounts at the WAC fee schedule. These fees are necessary to meet plumbing license requirements in Washington.
Fee Description | Amount | Effective/Notes | Source |
|---|---|---|---|
Initial Issuance / Renewal | $139.10 | Valid until July 1, 2026 | |
Designated Plumber Assignment/Change | $50.00 | Per assignment/change | |
Reinstatement (after lapse/suspension) | $69.50 | Pay if license lapses or is suspended | |
Bond (surety or savings assignment) | $6,000 | Continuous bond required | |
General Liability Insurance | $250,000 CSL (or $200k plus $50k split) | Minimum coverage; L&I as certificate holder |
There is no exam fee for the contractor license, since no exam is required. Fees related to individual plumber certification are separate and not included here.
Renewal and Continuing Education
Plumbing contractor licenses in Washington must be renewed every 24 months. L&I will notify you before your license expires. Complete renewal before your expiration date to avoid penalties or a lapse in licensure. Renewal is an ongoing part of plumbing license requirements in Washington.
Renewal Cycle and Late Penalties
Your license is valid for 24 months from issuance. Renewal requires another payment of the $139.10 renewal fee (as of Nov 2026, see the current schedule). If your bond or insurance lapses, or you miss the renewal deadline, L&I will suspend your license and mail a notice to your business within two days. To reinstate within the allowed period, you must provide up-to-date documentation and pay the $69.50 reinstatement fee to meet plumbing license requirements in Washington.
Continuing Education
There are no continuing education requirements for the plumbing contractor license itself. Contractors do not have to complete CE or submit proof for license renewal. However, individuals renewing their journey-level or medical gas plumber certification (the designated plumber) must follow separate continuing education protocols, which do not apply to the business entity license. For licensees who only hold the plumbing contractor license, you only need to maintain active bond, insurance, and designated plumber assignment to renew successfully. These are critical plumbing license requirements in Washington for ongoing compliance.
Reciprocity
There are no reciprocity or license endorsement agreements for the Washington plumbing contractor license with other states. According to L&I, only individual plumber certification may offer reciprocity with select states, but the plumbing contractor business license has no formal reciprocity or endorsement pathway. Every business wishing to contract plumbing work in Washington must complete all standard application steps and assign a Designated Plumber certified by Washington L&I to meet plumbing license requirements in Washington.
Therefore, if you are already a licensed plumbing contractor in another state, you must still complete all bonding, insurance, and application steps to obtain a Washington license before performing any plumbing work.
