How to Verify a Licensed Plumber in Delaware

Delaware requires all plumbing contractors to be licensed through the Delaware Division of Professional Regulation (dpr.delaware.gov). A $10,000 surety bond is required, and performing plumbing work without a license in Delaware is a violation of state law. Verify any plumber's credentials at dpr.delaware.gov before signing a contract or allowing work to begin.

This guide covers Delaware's plumber licensing requirements, the license tiers, how to verify credentials, and what else to check before hiring.

Does Delaware require plumbers to be licensed?

Yes. Delaware requires plumbers and plumbing contractors to hold a valid license from the Delaware Division of Professional Regulation (DPR) at dpr.delaware.gov. All trades are licensed in Delaware — there is no project-size exemption for plumbing work. Individual plumbers must hold a Master or Journeyman Plumber license, and plumbing contracting businesses must hold a contractor license. Performing unlicensed plumbing work in Delaware can result in fines and stop-work orders.

Delaware's DPR oversees a comprehensive licensing system covering all major construction trades. For plumbing, the DPR requires contractors to pass exams, carry bonding and insurance, and renew licenses on the required schedule. The DPR's public license database allows consumers to verify any plumber's credentials for free.

The EPA estimates that household plumbing leaks waste more than one trillion gallons of water per year in the United States. Delaware's coastal and tidal geography makes water management especially important — improperly installed plumbing can cause flooding, contamination, and structural damage that is particularly costly to remediate in the state's low-lying areas.

What plumber license types does Delaware issue?

Delaware's DPR issues Master Plumber, Journeyman Plumber, Apprentice Plumber, and Plumbing Contractor licenses. A Master Plumber holds the highest individual license — authorized to supervise, design, and permit plumbing work and serve as the qualifier for a licensed plumbing contracting business. Journeyman Plumbers perform field work under master oversight. The Plumbing Contractor is the business-level license.

Delaware plumbing license tiers:

• Plumbing Contractor— Business-level license for companies contracting to perform plumbing work. Requires a qualifying Master Plumber on staff.
• Master Plumber— Highest individual license. Can supervise, permit, and design plumbing systems.
• Journeyman Plumber— Licensed to perform most plumbing work under master oversight.
• Apprentice Plumber— In a supervised training program. Cannot work independently.

What bond does a Delaware plumbing contractor need?

Delaware plumbing contractors must carry a $10,000 surety bond as a condition of their DPR license. The bond provides financial protection if the contractor fails to complete work or violates code requirements. Beyond the bond, verify active general liability insurance (at least $300,000 for residential work) and workers' compensation for all employees. Request certificates and verify coverage directly with the insurer before any work begins.

How do I verify a plumber's license in Delaware?

Go to dpr.delaware.gov and use the DPR's free public license lookup. Search by the plumber's name, business name, or license number. Confirm the license type (Master Plumber, Journeyman Plumber, or Plumbing Contractor), the status is active, and the expiration date has not passed. Delaware plumbing licenses require periodic renewal — an expired license means the individual or company is not currently authorized.

What to verify in the search results:

• License type— Plumbing Contractor for the business; Master or Journeyman for the individual.
• Status— Active. Any other status means not authorized.
• Expiration date— Must be current before work begins.
• Business name— Should match the company on your contract.
• Complaint history— Review any prior DPR disciplinary actions.

What permits are required for plumbing work in Delaware?

Most plumbing work in Delaware requires a permit from the local building department or county authority. Delaware's three counties — New Castle, Kent, and Sussex — each have their own building code enforcement. Your licensed plumber should pull the required permit before starting work. Unpermitted plumbing can fail home sale inspections, void insurance, and create health risks if the work involves water supply or wastewater systems.

CheckLicensed.com lets you verify any Delaware plumber's license for just $0.99. Confirm the DPR license is active at dpr.delaware.gov or use CheckLicensed.com to check credentials before any plumbing work begins on your property.