Laws and rules about plumbing contractor licensing can be found in:
- Washington Administrative Code (WAC) Chapter 296-400A.
- Revised Code of Washington (RCW) Chapter 18.106.
The laws and rules are maintained and updated by the State Office of the Code Reviser.
Rule development
2025 rulemaking
Online insurance
L&I is considering changes to state contractor registration and plumbing contractor licensing rules. The changes under consideration would require insurance companies to electronically submit insurance documents and information to transition to an online insurance system for contractor registration and plumbing contractor licensing.
The changes would affect rules under:
- Chapter 296-200A WAC, Contractor Certificate of Registration Renewals - Security - Insurance; and
- Chapter 296-400A WAC, Plumber Certification Rules
About the rulemaking
Currently, L&I accepts paper copies of general liability insurance certificates, reinstatements, and cancellations for contractor registration and plumbing contractor licensing by mail and in-person. Either insurance companies or contractor applicants can submit the documents. This process is time-consuming, costly, and inefficient for both the agency and customers.
L&I is considering changes to only accept the documents electronically from insurance companies through the online insurance system known as the Electronic Bond and Insurance Policy System (EBIPS). L&I would no longer accept paper copies by mail, in-person, or through any other electronic method for contractor registration or plumbing contractor licensing. The only exception would be for first-time applicants for contractor registration or plumbing contractor licensing; these first-time applicants could submit insurance documents and information in-person or by U.S. Postal Service mail.
Opportunities to comment
L&I filed a Pre-proposal Statement of Inquiry (CR-101) on April 22. This formally started the rulemaking process. L&I will seek input on the rule development from stakeholders and interested parties.
Rulemaking documents
Notice of intent (04/22/2025)
CR-101 Pre-Proposal Statement of Inquiry.
Here’s what happens next
- Sept. 2, 2025: Proposed rules (CR-102) are expected to be filed.
- October 2025: Public hearings tentatively scheduled on the proposed rules.
- Nov. 18, 2025: Final rules (CR-103) are expected to be adopted.
- Jan 15, 2026: New rules would take effect.
Rulemaking for new legislation
During the 2020 legislative session, the Legislature enacted changes to state plumbing laws (Senate bill 6170). The changes included:
- Creating a plumbing contractor license.
- Creating a new residential service plumbing certificate.
- Modifying supervisory ratios of plumber trainees to certified plumbers.
- Authorizing remote supervision of plumber trainees in certain circumstances.
- Increasing the number of members on the Advisory Board of Plumbers.
These changes have required L&I to conduct the rulemaking process to implement the new laws. This is the third phase of rulemaking for the plumbing changes.
The agency filed a preproposal on Jan. 18, 2022, to consider changes to Chapter 296-400A WAC, Plumber Certification Rules. The changes under consideration include:
- Adding new fees and penalties.
- Modifying definitions.
- Modifying plumbing certificates and competency examinations.
- Modifying records and licenses that plumbing contractors must keep and report.
- Making updates, clarification, and housekeeping changes.
L&I is also considering a 5.58% fee increase for fiscal year 2023 for plumbing licenses, certifications, and other Plumber Program public safety activities. The fee increase is needed to cover operating expenses.
For details on the changes, see the CR-101 Preproposal Statement of Inquiry below.
Rulemaking documents