How to find the owner of a licensed contractor in Washington, Oregon, Arizona or Colorado (free, from the registries)

Puget Sound contractor list: owner names and licence years from the WA L&I registry

A cold letter that opens with the owner's name gets read; one that opens with "Dear business owner" does not. For licensed trades the owner's name is usually public, because the state that issued the licence publishes who holds it. This is where it lives in the four states our contractor lists cover, with the dataset ids so you can check any row yourself.

Washington: L&I contractor registry

The Department of Labor & Industries publishes every registered contractor as open data on data.wa.gov (dataset m8qx-ubtq). The field PrimaryPrincipalName is the principal on record, written LAST, FIRST MIDDLE; LicenseEffectiveDate and LicenseExpirationDate give how long the company has been licensed; ContractorLicenseStatus tells you whether it is active; PhoneNumber lets you join the registry to a map listing by phone, which is far more reliable than matching names. A second dataset (4xk5-x9j6) lists every principal, not just the primary one.

Oregon: CCB licence list

The Construction Contractors Board publishes its licence file on data.oregon.gov (dataset g77e-6bhs). rmi_name is the Responsible Managing Individual, the person who passed the exam and answers for the company; orig_regis_date is the original registration date; lic_exp_date the expiry; endorsement_text the licence class; and, unusually, ins_company and bond_company name the insurer and the surety. The file carries a phone number, so it joins cleanly.

Arizona: ROC posting list

The Registrar of Contractors publishes a CSV of every active licence at roc.az.gov/posting-list, refreshed by the Registrar (the October 2026 file holds 58,444 records). Columns: licence number, business name, "doing business as" name, class (CR-11 electrical, CR-37 plumbing, CR-39 air conditioning and refrigeration, CR-42 roofing, and the C- and R- variants), qualifying party, issue date, expiry date and status. The qualifying party is the person who holds the qualification for the licence; it is usually the owner or the lead tradesperson, and when the field says QP Exempt no person is named. The file has no phone column, so a join to map data has to go by name.

Colorado: DORA professional licences

Colorado licenses electrical and plumbing contractors at state level (HVAC and roofing are licensed, if at all, by the city or county). The Division of Professions and Occupations publishes every licence on data.colorado.gov (dataset 7s5z-vewr). Filter licensetype to EC (electrical contractor) or PC (plumbing contractor): you get entityname, the first-issue, last-renewal and expiry dates and the status, but no owner and no phone. The individual master-electrician and master-plumber records carry names, but nothing in the file ties them to a company.

What is not published

Nevada's State Contractors Board offers a search page and a public-records request, not a file. Idaho's contractor registration has a lookup only. Utah sells its licensee download. For those states a list can still carry phone, website, published email and social profiles from map data, but the owner's name has to come from the company's own website, when it is there.

Doing it at scale

By hand this is one lookup per company. Our contractor lists do the join for a whole metro: the businesses come from Overture Maps places (the open map dataset built by Amazon, Meta, Microsoft and TomTom), then each row is matched to the registry by phone where the registry has one, otherwise by normalised name, and the owner or qualifying party, licence dates, class and number are written next to the phone, website, published email and socials. Where the registry names nobody, the company's own About, Team and Contact pages are read next: a name is kept only when the page also carries the company's own name or phone (so a wrong website in the map data cannot lend it a stranger), and the page it came from is written in the row as contact_source, so you can check it before you write. Every count on a product page is computed from the file you download, and a 25-row sample with the real columns is linked on each page.

Related: how many of these contractors have no website, counted from the same files.

By Addison Lopez, Workshop Media Co. Counts are from the October 2026 editions (site-read names added October 23). Registry fields and dataset ids checked October 22, 2026; the registries change their schemas occasionally, so verify against the source before building on them.