List Dover, Delaware Contractor and Trade Licences

Say you have just taken over the counter at an electrical and HVAC supply house in Dover, and the owner wants a mailer out before the winter heating rush: every contractor firm with a Dover address, plus a count of the licensed electricians and HVACR techs in town so you know how many trade accounts there are to win. Delaware licenses both, but in two different places. The firms hold a business licence from the Division of Revenue; the tradespeople hold a licence from the Division of Professional Regulation. On 2026-10-07 the two rosters together had 881 Dover entries.

The manual way, and what it costs

Both rosters are public-domain datasets on data.delaware.gov, each with an Export button, and that is a perfectly good route for a one-off. Download the business-licence file, filter category to the four contractor categories and city to DOVER, then download the professional-licence file, filter it to the Electrical Examiners and Plumbing/HVACR boards, Active status, and Dover. If you are comfortable in a spreadsheet, that is an hour and it is free.

What makes it more than an hour is the clean-up. The business file holds every kind of Delaware business licence, statewide; contractors are 13,417 of its rows and a firm appears once per trade name, so you have to collapse duplicates by licence number. The professional file covers 38 professions and keeps expired and revoked licences next to active ones, and it lists homeowner electrical permits among the electricians. Do it again in January, after the year-end renewals, and you repeat every step.

The faster way

Delaware Contractor License Lookup & List Scraper (DOR + DPR) does the same search once and hands back every row at once.

{
  "city": "Dover",
  "maxResults": 1000
}

Leaving source at its default of both is what you want here: the run returns the 670 Dover business licences first and the 211 active Dover trade licences after them, each row tagged with the roster it came from. city is an exact match on the licence’s city, so it does not pick up a firm on Dover Road in another town. maxResults at 1000 sits above the 881 that match, so the list is complete; the run took 2.0 seconds locally.

What comes back

{
  "license_number": "1989012229",
  "dataset": "business_license",
  "license_category": "RESIDENT CONTRACTOR",
  "board": null,
  "residency": "resident",
  "status": null,
  "business_name": "VOSHELL BROS WELDING, INC.",
  "trade_names": [
    "VBW"
  ],
  "person_name": null,
  "issue_date": null,
  "valid_from": "2025-01-01",
  "expiration_date": "2027-12-31",
  "address": "5670 FORREST AVE",
  "city": "DOVER",
  "address_state": "DE",
  "zip_code": "19904-5112",
  "source_url": "https://data.delaware.gov/resource/5zy2-grhr.json?license_number=1989012229"
}

Field	Example value	Meaning
dataset	business_license	business_license (Division of Revenue) or trade_license (DPR)
business_name	VOSHELL BROS WELDING, INC.	Legal business name
trade_names	["VBW"]	Other ‘doing business as’ names on the same licence
address	5670 FORREST AVE	Street address (business licences only)
license_category	RESIDENT CONTRACTOR	Business category, or DPR licence type on trade rows
person_name	—	Licensee’s name (trade licences held by individuals)

For the mailer, the business rows are the ones that matter, and every one of the 670 has a street address. 488 are filed as RESIDENT CONTRACTOR and 178 as NON-RESIDENT CONTRACTOR, and 7 of them have a Pennsylvania address, so check address_state before you print. 228 carry at least one trade name in trade_names, which is the name on the truck and often the better salutation. The trade rows answer the second question: 161 Dover electrical licences (74 journeyperson, 41 apprentice, 30 master) and 50 plumbing and HVACR licences, including 25 Master HVACR.

What you’d do with it

Export to CSV and split on dataset. The business rows go straight into the mail merge, addressed to the trade name where there is one. The trade rows have no street address, so they are a sizing number and a name list for the counter rather than a mailing list; sort them by license_category and you know there are 30 master electricians in Dover who might each run a shop. Re-run in January: 476 of the 670 business licences show an expiry of 2026-12-31, so the January list shows who renewed.

Worth knowing

There are no phone numbers or emails in either roster, on any row, and the actor does not add them. Trade licences carry only a city, state and ZIP, so you cannot mail an individual electrician from this data.

The two rosters are not joined. A Dover electrical firm’s business licence and its master electrician’s DPR licence share no key, so this run cannot tell you which tradesperson works for which firm, and the actor does not guess by matching names. The data is current to the state’s last refresh, which was September 29, 2026 for both datasets when we ran it, and valid_from is the start of the current licence term, not the year the firm was founded.

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Run it yourself: How to run Delaware Contractor License Lookup & List Scraper (DOR + DPR) walks the whole thing step by step, including the 20,420-row statewide export.

If the same owner has a branch in Omaha, Nebraska Contractor Registration Lookup & Leads Scraper builds that county list from Nebraska’s registry, and can add a phone number per firm. For a Mid-Atlantic list that carries an email address on most rows, use Virginia Contractor License Lookup (DPOR Bulk).