Delaware Plumber License Requirements (2026)

The Delaware Board of Plumbing, HVACR, and Master Pipefitters, under the Division of Professional Regulation, licenses plumbers statewide under Delaware Code Title 24 Chapter 18. Delaware issues three plumber classifications: Apprentice Plumber, Journeyperson Plumber, and Master Plumber. The Master Plumber license authorizes the holder to contract for plumbing work of any kind in Delaware and to serve as the qualifying individual for a plumbing business. All Delaware plumber examinations are based on the International Plumbing Code and Delaware State Plumbing Code amendments. A Master Plumber who contracts for work must also hold a Delaware Division of Revenue business license.

Governing Authority

This license is issued and enforced by Delaware Division of Professional Regulation (DPR) pursuant to Delaware Code Title 24 (Professions and Occupations); Title 30 (Business License, Division of Revenue). The Delaware Division of Professional Regulation administers the trade licensing boards for electricians, plumbers, HVACR, and master pipefitters. Delaware does not issue a state general contractor license — any person doing contracting work in Delaware must instead hold a Delaware Business License from the Division of Revenue.

Official portal: https://dpr.delaware.gov/
Address: Cannon Building, 861 Silver Lake Blvd, Suite 203, Dover, DE 19904
Phone: (302) 744-4500

Eligibility Requirements

At a minimum the applicant has to be 18 years old and supply a valid Social Security Number. No Delaware residency requirement.

Good moral character

The Board conducts a fitness review on every applicant. Criminal convictions are reviewed individually under 24 Del. C. § 1820.

Background investigation

Mandatory criminal history disclosure on the application. The Board may require a state and federal background check.

Experience & Education Matrix

The applicant must document and verify at least 7 years of Master Plumber requires seven years of practical plumbing experience, at least two of which must be as a licensed Delaware Journeyperson Plumber. Journeyperson requires five years (10,000 hours) of apprentice-level experience under a licensed Master Plumber.. Keep payroll, tax, project, or supervisor records to support the claim, as the board can request proof for any period within its lookback window.

Accepted proof of experience or eligibility

Board Experience Verification Form signed by each licensed Master Plumber supervisor
W-2 statements, pay stubs, or 1099 records for the qualifying period
Approved plumbing apprenticeship completion certificate (where applicable)

Education substitution

Completion of a U.S. Department of Labor registered plumbing apprenticeship satisfies the Journeyperson experience requirement. Accredited plumbing trade school programs may substitute for portions of the experience at the Board's discretion.

Examination Structure

The licensing examination is delivered by Prometric (under contract to the Delaware Board of Plumbing, HVACR, and Master Pipefitters). All of the following parts must be cleared prior to issuance:

Delaware Master Plumber Examination — International Plumbing Code, Delaware Plumbing Code amendments, and business and law — 100 questions, 240 minutes, passing score 75%

Examination fee: $79 examination fee paid to Prometric at scheduling.

Retake policy: Failed examinations may be re-taken by paying a new Prometric fee. The application remains valid for one year from Board approval.

Insurance & Financial Security

This credential carries no state-level surety bond requirement under the cited sources. Individual jobs may still trigger a permit or public-works bond, which should be verified before bidding.

General liability

Delaware does not impose a state-level general liability minimum for plumbers. Commercial owners commonly require $1,000,000/$2,000,000.

Workers' compensation

Workers' compensation coverage is mandatory under Delaware Code Title 19 Chapter 23 for any employer with one or more employees.

Additional financial requirements

No financial statement is required by the Board.

Application and License Fees

Fee	Amount
Application (non-refundable)	$174
Examination	$79
Initial license	$174
Renewal (every 2 years)	$174

Maintenance & Renewal

Expect to renew the Delaware Master Plumber (Board of Plumbing, HVACR, and Master Pipefitters) every 2 years. Renewal currently costs $174. Delaware plumber licenses renew every two years on June 30 of odd-numbered years.

Continuing education: Ten hours of Board-approved continuing education per two-year renewal cycle, including code updates.

Downloadable Asset

2026 Delaware Plumber License Roadmap (PDF) — a printable step-by-step checklist for the application process.

Download the PDF roadmap →

Reciprocity and Endorsement

Delaware does not accept the NASCLA Accredited Examination for this classification.

Reciprocal State	Accepted Exam	Conditions
No formal bilateral reciprocity agreements identified.

Delaware does not maintain formal statutory plumber reciprocity agreements. The Board may waive portions of the experience requirement for applicants who hold an equivalent active master plumber license in another state for at least two years.

Weighing more than one jurisdiction? The national hub compares Plumber license requirements in every state — exam, bond, fee, and experience thresholds side by side.

Step-by-Step Application Roadmap

Register as an Apprentice Plumber. Enroll in a Board-approved plumbing apprenticeship before performing plumbing work in Delaware.
Complete 10,000 hours over five years. Work under a licensed Delaware Master Plumber to accumulate qualifying apprentice hours.
Pass the Journeyperson Plumber exam. Prometric plumbing code examination at 75% or higher.
Work two years as a Delaware Journeyperson. Accumulate at least two years of active Journeyperson experience under a Master.
Submit the Master Plumber application. File the Board application with documented experience and Board fee.
Pass the Master Plumber exam. Prometric Master Plumber examination at 75% or higher.
Obtain the Delaware Business License. Register with the Division of Revenue before contracting plumbing work in Delaware.

Pre-Submission Checklist

The most critical documents or confirmations the applicant should have in hand before filing with DPR:

☐ Apprentice Plumber registration
☐ 10,000 hours of documented plumbing experience
☐ Delaware Journeyperson Plumber license
☐ Two years of Journeyperson experience
☐ Master Plumber application with Board fee
☐ Prometric Master Plumber exam pass at 75%+
☐ Delaware Division of Revenue business license
☐ Workers compensation coverage (if employees)

Study and Reference Materials

The references below are either cited by the board, used during the application, or standard preparation for the trade. They are listed purely for convenience — CLR earns no commission on any of them.

International Plumbing Code (Delaware-adopted edition) — International Code Council. Primary technical reference. Open-book at Prometric.
Delaware State Plumbing Code amendments — State of Delaware. Required amendments to the IPC.
Delaware Code Title 24 Chapter 18 and Board Rules — State of Delaware. Licensing law and Board rules.

Common Filing Mistakes

Based on the board's own instructions and the sources cited here, the problems below are what most often stall a Delaware Plumber application.

Skipping apprentice registration

Hours worked before registering as a Delaware apprentice are not counted toward the Journeyperson experience requirement.

Counting out-of-state Journeyperson time

The two-year Journeyperson prerequisite must be active Delaware licensure unless the Board approves an equivalency.

Wrong code edition

The exam is based on the Board-adopted IPC edition plus Delaware amendments. Studying the wrong edition is a common failure.

Missing the business license

Master Plumbers who contract work without a Division of Revenue business license are subject to fines.

Letting CE slip

Ten CE hours are required each renewal. Missed CE blocks renewal.

Other Delaware Trade Licenses

If the Plumber license is not the right fit, the following published Delaware trade guides are also covered by CLR:

Frequently Asked Questions

What are the Delaware plumber license classes?

Apprentice, Journeyperson, and Master. Master Plumber is the broadest and is required to contract for plumbing work in Delaware.

How many hours does Delaware require for a Master Plumber?

Five years (10,000 hours) as an apprentice to qualify for the Journeyperson exam, plus two additional years as a Journeyperson to qualify for the Master exam — seven years total.

What code does the Delaware plumber exam use?

The International Plumbing Code as amended by the Delaware State Plumbing Code and adopted by the Board.

Does Delaware have plumber reciprocity?

No formal statutory reciprocity. The Board may grant experience equivalency for out-of-state master plumbers with at least two years of active licensure elsewhere.

Do I need a business license to contract plumbing work in Delaware?

Yes. Any Master Plumber who contracts for work must also register with the Division of Revenue for a Contractor Business License.

Primary Sources

Regulatory requirements on this page are drawn from the official board, statute, and exam-provider materials listed below.

Verified 2026-05-13 · Next scheduled review 2026-08-11