Apply for examination

Depending on the date of your application and your birthdate, your initial certification will be good for:

  • A minimum of 25 months up to a maximum of 37 months for journey level, residential, residential service, backflow, or domestic pump or pump and irrigation plumbers.

Your initial fees are the same regardless of the length of time, they are not pro-rated. Your renewal date is on your birthday.

To apply for a new plumber exam or reciprocal certification online, you will need:

  • Your Social Security number.
  • An electronic payment: We accept Visa, MasterCard, Discover, and American Express credit or debit cards. We also accept electronic checks (E-Check) – a one-time withdrawal from your checking account.
  • The required documents on file with L&I to support your application:
    • Plumber trainees — Verify that your affidavits of experience documenting your required years and hours of experience in Washington are on file with L&I. You can verify your hours by calling our office at 360-902-5207 or emailing us at plumbers@Lni.wa.gov.
    • Reciprocal applicants — Washington State reciprocates with the state of Idaho. Email a copy of your active Idaho journey level card and a copy of your government-issued photo ID to plumbers@Lni.wa.gov or mail to Plumber Certification, P.O. Box 44470, Olympia, WA 98504.
    • Out-of-state applicants — If you do not qualify for the Idaho reciprocal certificate, email:
      1. Copies of your active out-of-state plumbing license and your government-issued photo ID, OR
      2. Documentation of your U.S. military experience to plumbers@Lni.wa.gov or mail to Plumber Certification, P.O. Box 44470, Olympia, WA 98504 for consideration.
  • Required Fees
    • $160.85 for your examination
    • Upon successful completion of your exam, we will send you an invoice for the appropriate certification fee:
      • $193.15 – Journey Level / Residential / Residential Service.
      • $193.25 – Domestic Pump / Pump and Irrigation.
      • $133.25 – Backflow Specialty.

Apply by mail

To apply by mail, print the Plumber Certification Application and follow the directions on the form.

Apply in person

You can apply in person at any L&I field office.

What L&I will do:

  • Process your affidavits of experience, verify your reciprocal information, or out-of-state license information.
  • Mail an examination notice if your application is accepted.
  • Mail a notice requesting an additional certification fee once reciprocal is approved.
  • Send a letter if the application or reciprocal is denied, stating the reason for denial.
Renew your certification

Your plumber certification renews on your birthdate every 3 years for journey level, residential, residential service, backflow, and domestic pump and pump and irrigation plumbers.

Renew online

To renew your plumber or reciprocal certification online, you will need:

  • Your 12-digit certification (license) number.
  • Your Social Security number.
  • An active journey level or specialty plumber certification (not suspended or canceled).
  • Proof of your continuing education on file with L&I from your course provider.
    • Note: If you do not complete your continuing education by your expiration date, late fees will apply and you will be unable to renew online.
  • An electronic payment: We accept Visa, MasterCard, Discover, and American Express credit or debit cards. We also accept electronic checks (E-Check) – a one-time withdrawal from your checking account.
  • Required Fees
    • $193.15 – Journey level, residential specialty, & residential service plumber certification renewal.
    • $193.25 – Domestic pump or pump and irrigation specialty plumber.
    • $133.25 – Backflow assembly tester renewal.

Note: You cannot renew online if you have any outstanding, unpaid plumbing infractions, or your certificate is suspended.

Renew by mail

To renew your existing plumber certification, print the Plumber, Medical Gas, or Trainee Renewal form and follow the instructions on the form.

Renew in person

You can apply in person at any L&I field office.

Renewal requirements and fees

Plumber Classification Continuing Education Requirements Renewal Fee Late Fee*
Journey Level (PL01)Residential (PL02) Residential Service (PL04) 16 hours before their expiration until 07/01/2021. On 07/01/2021 renewals will need 24 hours before their expiration. ** $193.15 $193.15 ($386.30 total)
Medical Gas Endorsement (MG01) Affidavit of Continuity $132.80 $132.80 ($265.60 total)
Pump and Irrigation (PL03)Domestic Well (PL03A) 24 hours before their expiration*** $193.25 $193.25($386.50 total)
Backflow Assembly Tester (PL30) Current copy of BAT certification from Washington Department of Health $133.25 $133.25 ($266.50 total)

* The late fee is a double fee that applies to late renewals or for those who haven’t completed their continuing education requirements by their renewal date.

** These 16 hours must consist of a minimum of 8 hours Plumbing Code (Code) and a minimum of 4 hours IRE. The other 4 hours may be from any category (Code, IRE, IRP) until 07/01/2021.

On 07/01/2021 24 hours must consist of a minimum of 12 hours of Plumbing Code (Code) and a minimum of 4 hours IRE. The other 8 hours may be from any category (Code, IRE, IRP).

*** These 24 hours must consist of a minimum of 12 hours of electrical and 12 hours of plumbing (Code, IRP).

  • If you pay your renewal fee on time but you don’t complete your continuing education on time, late fees will apply. You cannot pay your late fee online. You will need to mail it in or pay at a service location.
  • 90 calendar days after your certification has expired – If you haven’t paid your renewal fee and/or you haven’t completed your continuing education requirements, you must retest to reinstate your certification. A retesting fee of $160.85 will apply along with your certification fee.

Verify your certification

After you have applied for or renewed your certificate, use our Verify a Contractor, Tradesperson, or Business tool to look yourself up and make sure your certification shows your new expiration date.