Which license each job needs in Boulder
| Work | City of Boulder license | Also needed | Boulder permits (firms) |
|---|---|---|---|
| Remodel, addition, ADU, new home on a one- or two-family house | Building contractor Class C (or A or B) | — | remodel 1,178 (414); additions 369 (186) |
| Roofing | Class D-2 Roofing (or a general class) | — | 2,516 (426) |
| Siding | Class D-3 Siding | — | inside remodel above |
| Fences, minor work under $2,000 and 200 sq ft | Class E | — | — |
| Furnace, heat pump, AC | Mechanical contractor license | — | HVAC 4,460 (324) |
| Plumbing, water heaters | Plumbing contractor license | Colorado master plumber, held or employed (DORA) | water heaters 1,267 (125) |
| Electrical, solar, EV chargers | Registration with the City (no fee) | Colorado master electrician and electrical contractor card (DORA) | electrical 1,330 (355); solar 1,489 (112) |
The rules are on the City's Contractor Licensing page (read 22 October 2026). "Boulder does not accept reciprocal licenses from other jurisdictions", and licenses are "for work being performed INSIDE city limits". Other than a homeowner on their own home, "no person shall perform any work as a contractor in the city without first obtaining a city contractor's license", and "Permits will not be issued" to anyone without a valid, current license for the type of work. Class C covers "any detached One-and-Two Family Dwelling or Town home and their accessory structures not more than two stories in height and of Type V construction". A plumbing contractor must be, or have in charge, "a master plumber currently licensed by the Colorado State Plumbing Examiner's Board"; an electrician registers with "a valid State of Colorado Electrical Contractor's Card" and a state master electrician.
Every licensee must keep general liability of "$1,000,000 per occurrence and a $2,000,000 aggregate limit" plus workers' compensation. The usual Boulder remodel permit carries $25,862 and the usual addition $100,000; that insurance floor is what stands behind them.
How to run the lookup in five minutes
- Ask for the City license number and class. A D-2 roofer is not licensed to build your addition.
- City license: use the search on the City's Customer Self Service portal, or download Licensed Contractors from Boulder Open Data, which the City says "updates regularly".
- Electrician or plumber: search DORA's Verify a License for the master's name and check it is active.
- Questions: Contractor Licensing, 303-441-1982, cobcontractorlicense@bouldercolorado.gov.
- Track record: open the firm on our Boulder roofer list, HVAC list or remodeler list.
How to search Boulder permit records
The same Customer Self Service portal holds the permits. The City's records page says it "has an address and case number search for general viewers and registered accounts", with "contractor names and inspection dates", and that "Inspections in the city of Boulder are pass/fail." Construction permits are also downloadable from Boulder Open Data. The City keeps plan documents only "for new construction or major modifications", so for most jobs the permit entry is the whole record.
The portal is organised by address. Ours is organised by firm: each firm's Boulder permits, its license match, the share that passed final inspection and the days it took, on the Boulder permit statistics page and the compare lists.
What 12,984 Boulder permits show
| Trade | Permits | Firms | Passed final | Usual days to final | Firms matched to a current City license |
|---|---|---|---|---|---|
| HVAC & mechanical | 4,460 | 324 | 70.2% | 76 | 73.1% |
| Roofing | 2,516 | 426 | 86.3% | 41 | 65.5% |
| Solar & battery | 1,489 | 112 | 93.8% | 72 | 73.2% |
| Electrical | 1,330 | 355 | 76.2% | 55 | 67.9% |
| Water heater | 1,267 | 125 | 50.9% | 137 | 76.0% |
| Remodel & repair | 1,178 | 414 | 80.6% | 141 | 72.0% |
"Passed final" is the share of permits a year or more old that passed final inspection; a permit that expired without one counts as not finished. Water heaters stand out: only 50.9% passed final, so on a swap, ask who books the inspection. Among the 55 HVAC firms with 10 or more permits, the 10th-percentile firm passed 44.9% and the 90th 87.4%.
See every Boulder roofer by license and permits passed →
Red flags in Boulder
- A license from Boulder County, Denver or another city offered as if it covered work inside Boulder city limits.
- A class that does not fit the job, such as a D-2 roofer quoting a kitchen or an addition.
- A request that you apply as the homeowner. The homeowner exception covers your own residence, "one such building or structure during a calendar year".
- An electrician or plumber with no Colorado license number.
- A firm that has gone quiet: 12 electrical firms and 7 roofers with 5+ permits filed none in the last 12 months of our data.
What this lookup does not tell you
Our license status is a name match against the City's list, which holds current licenses only: 34.5% of roofing firms did not match, which can mean a lapsed license or just a different spelling. DORA's state licenses are not linked. A license says the firm may work in Boulder, not how its last job went. Our data stops at September 2026. Denver's and Colorado Springs' schemes and the state rules are in How to check a contractor's license in Colorado.
How we know this
Permits are City of Boulder construction permits on homes, 2023-10 to 2026-09, grouped into the trades above. "Passed final" uses permits a year or more old; days are issue to completion from the City's dates. License status is our name match against the City of Boulder's licensed contractors list. City text is quoted from bouldercolorado.gov, read 22 October 2026.
Numbers come from City of Boulder construction permits, data through October 16, 2026. Nobody paid to be on this page and nobody can.
Questions
- Who licenses contractors in Boulder, Colorado?
The City of Boulder, for building, roofing, siding, mechanical and plumbing contractors working inside city limits; it does not accept licenses from other jurisdictions. Electricians and plumbers also need a Colorado license from DORA, and electricians register with the City.
- Which Boulder license class can remodel a house?
Class C covers building, altering or repairing a detached one- or two-family dwelling or townhome of Type V construction up to two stories, plus its accessory structures. Class A and B cover larger buildings; D-2 is roofing only, D-3 siding only.
- Where do I check a Boulder contractor's license?
Search the City's Customer Self Service portal (bouldercolorado.gov/energovcss) or download the Licensed Contractors list from Boulder Open Data. Contractor Licensing is on 303-441-1982.
- How much insurance must a Boulder contractor carry?
General liability of at least $1,000,000 per occurrence and $2,000,000 aggregate, plus workers' compensation as Colorado law requires, with the City listed as additional insured.
- Can a Boulder homeowner do the work without a license?
Yes, on their own residence or an accessory structure for personal use, but the exception covers only one such building or structure per calendar year, and a Homeowner Contractor License application is required.
Build your own list
Every firm with that kind of permit on record. Pick what you value. The list moves.
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- Contractor Licensing — City of Boulder (2026-10-22)
- Licensed Contractors — City of Boulder Open Data (2026-10-22)
- EnerGov Customer Self-Service Portal — City of Boulder (2026-10-22)
- Planning & Development Services Records Request Resources — City of Boulder (2026-10-22)
- Verify a Colorado Professional or Business License — DORA (2026-10-22)