Plumber License from Iowa to Delaware: Does It Transfer? (2026)

What's different between Iowa and Delaware

Computed from both states' verified data rows, in both directions, and from the route every other origin gets into Delaware. Exam notes are our summary of each board's published rules, with sources below.

Route, each way

Iowa to Delaware (this page): Reciprocity agreement.

Delaware to Iowa (the reverse move): Licensure by endorsement.

The two directions differ: Iowa and Delaware do not give each other's licensees the same route.

Does coming from Iowa matter?

Coming from Iowa matters here: only 3 of 50 origins (the other 49 states and DC) get this result for a move into Delaware.

The others get: licensure by endorsement (38) and no state license to transfer (9).

Reciprocity agreements

Delaware's reciprocity agreement list names 3 states (Connecticut, Iowa, and Maryland), including Iowa.

Iowa's reciprocity agreement list names 1 state (South Dakota), not including Delaware.

Application fee

Delaware lists $173 for an out-of-state applicant and Iowa lists $30–$180 for the reverse move; neither may be the full cost.

Processing time

Iowa lists up to 2 weeks for the reverse move; Delaware has no verified processing-time figure on file, so the two cannot be compared here.

Exam rules on record

Delaware and Iowa carry different exam notes (our summaries, below); any state law or jurisprudence exam is listed with each state's requirements.

• Delaware (this move): Delaware issues only Master Plumber licenses (no state journeyman license). It grants licensure by reciprocity — without the Delaware master examination — to Master Plumbers currently licensed in a state with substantially similar standards, presently Connecticut, Iowa and Maryland, with no additional experience required; Master Plumbers from 14 other named states qualify by reciprocity only after documenting at least 7 years of practice after Master licensure; applicants from any other jurisdiction have their state's law reviewed and otherwise qualify by examination (apprenticeship by-pass exam)
• Iowa (the reverse move): Iowa waives its journeyperson plumber exam only for applicants who hold a South Dakota plumbing license obtained on the basis of written examination (its sole reciprocity agreement, approved May 2016); every other out-of-state plumber must pass the Iowa journeyperson exam

What changes, Iowa → Delaware

The destination column is what you must satisfy — Delaware sets the rules for this move.

Step by step

1. Confirm Delaware's current requirements on the Delaware Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners — Division of Professional Regulation website (linked below) — rules change.
2. Submit the reciprocity application to the Delaware Board of Plumbing, Heating, Ventilation, Air Conditioning and Refrigeration Examiners — Division of Professional Regulation (application linked below).
3. Arrange license verification from your current state via the verification system.
4. Hold a current, good-standing Master Plumber license in another U.S. jurisdiction.
5. Reciprocity with no added experience is limited to substantially-similar states (currently Connecticut, Iowa, Maryland).
6. Reciprocity from Alabama, Arkansas, District of Columbia, Florida, Georgia, Michigan, New Hampshire, New Jersey, North Carolina, Ohio, Rhode Island, South Carolina, Virginia or West Virginia requires proof of at least 7 years of practice after Master licensure.
7. Delaware has no state journeyman plumber license; the 'journeyman certificate' is an apprenticeship-completion credential (e.g., via the Delaware Department of Labor), not a board license.
8. Pay the fees listed above, and allow for the processing time shown there.

Official links

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