Plumbing Contractors: Prepare for major changes on July 1

Starting in July, all plumbing work must be performed by a new license category of contractors called licensed plumbing contractors.

That work includes hiring certified plumbers, and offering, advertising and bidding for plumbing jobs – the types of work that general contractors and specialty plumbing contractors now perform.

The new license is among numerous changes to plumbing laws passed by the 2020 Legislature. Plumbing and related industries requested the revisions to improve public health and safety, expand plumber training opportunities and meet the rising demand for certified plumbers.

The Department of Labor & Industries (L&I) adopted final rules for plumbing contractor licensing on June 10, 2021.

Transition period for new license

Although the rules go into effect on July 1, they provide a transition period to allow applications for the new plumbing contractor license to be submitted and processed. Existing registered contractors will be considered in compliance with the new license requirements if they submit their application to L&I by Sept. 1.

However, L&I urges those who want the plumbing contractor license to apply as soon as possible. While waiting to receive their new license, applicants should maintain their existing registration to remain in good standing with permitting and compliance authorities.

What’s new for construction contractors on July 1

  • L&I will stop registering construction contractors in the specialty plumbing classification.
  • Current specialty plumbing construction contractors must apply for the new plumbing contractor license to continue doing plumbing work.
  • General construction contractors must subcontract plumbing to a licensed plumbing contractor.
  • Only licensed plumbing contractors can hire certified plumbers.
  • All plumbing work on site must be done by certified plumbers or properly supervised trainees; both must be employed by a licensed plumbing contractor.
  • Contractors can obtain both a plumbing contractor license and general contractor registration. This will allow them to do plumbing and non-plumbing construction.
  • Licensed plumbing contractors must complete an L&I form naming a full-time, certified plumber as their “Designated Plumber.”

Apply for new plumbing contractor license now

The application can be downloaded at

  • License requirements include a business license, general liability insurance, and a $6,000 bond or assigned savings account.
  • Fee for the two-year license is $139.10. Fee to file the “Designated Plumber” form with L&I is $50.
  • First-time applicants must submit the notarized applications and documents by mail.


For more information about the new plumbing requirements, go to

For information on the plumbing final rules, go to

For questions, contact the L&I Plumbing Certification Program at or call 360-902-5207.