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Colorado emissions test (Air Care Colorado): the official wording
Everything in quotation marks here is from 3 sources and was matched to them on November 11, 2026. The quotes are the sources’ words; ours only label them.
About these quotes.
The Colorado Department of Public Health and Environment and the Colorado DMV websites refused our request. The current lines here are the Air Care Colorado site’s own words; we treat it as a contractor-run program site, and the link we recorded to it is from a Colorado General Assembly page, not from an agency page. Lines from two General Assembly staff publications are kept apart at the end of the page, with the dates those publications print quoted just below; they are not used by the checker or the comparison table. Where we hold no line from a current source, the page says so.
The dates those publications print:
23 Dec 2016
A Legislative Council Staff Publication June 2017
On this page: where · how often · fee · new and older vehicles · diesel, electric, hybrid · check a vehicle · sources
What does the text call it?
There are 18 conveniently-located Air Care Colorado emissions facilities located throughout the Denver-metropolitan area and the North Front Range.
The page we point to: Air Care Colorado, FAQ: Quick Consumer Information. The agency’s own page, which our reader could not open: Colorado Department of Public Health and Environment website.
Which counties does the text name?
The quoted text names 9 counties:
- Adams County
- Arapahoe County
- Boulder County
- Broomfield County
- Denver County
- Douglas County
- Jefferson County
- Larimer County
- Weld County
This requirement applies to most vehicles with registered mailing addresses in the seven Denver-metropolitan area and North Front Range counties (Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, Jefferson, Larimer and Weld).
How often is the test?
Once they have reached age, most 1982-and-newer vehicles are inspected every two years while most 1981-and-older vehicles are inspected annually.
What does the test cost?
An inspection is $35. The only exception is a reduced fee ($20) for 1981-and-older vehicles.
What does the text say about new and older vehicles?
With few exceptions, all gasoline-powered vehicles require emissions inspections once they are over seven years old.
Shown with it, so that neither is read alone:
Most vehicles do not require an inspection until they are eight years old.
What about diesel, electric and hybrid vehicles?
Every current line we hold for Colorado that uses the word diesel, electric or hybrid. Some are about one place or one kind of test; each speaks for itself.
Yes; however, the diesel inspection is a separate program operated by the state of Colorado.
We hold no current official line we could read on some of these fuels beyond the lines above for Colorado. Older text, if we hold any, is at the end of this page.
What else does the text say?
Additionally, an inspection is required when a vehicle that is at least seven years old changes ownership.
NOTE: If your vehicle is registered in a county outside the program area but is driven at least 90 days a year into the program area for employment or school, an emissions inspection is required.
Typically, vehicles built before 1976 can be registered as collector vehicles and may not be required to have their emissions inspection.
What does older text say?
These lines are from two Colorado General Assembly staff publications, which print the dates quoted at the top of this page and may predate later changes. They are shown for reference and are not used by the checker or the comparison table.
Emissions testing of gas- and diesel-powered vehicles is required when registering or selling vehicles in Boulder, Broomfield, Denver, Douglas, and Jefferson counties, and in portions of Adams, Arapahoe, Larimer, and Weld counties, as shown in the Air Care Colorado program area maps
Parts of El Paso County also require diesel vehicles to obtain emissions testing prior to sale.
New vehicles are exempt from emissions testing requirements for the first seven model years.
Vehicles that are all-electric are exempt from emissions testing.
New diesel vehicles are exempt for the first four model years.
In 1980, the Colorado General Assembly created the Automobile Inspection and Readjustment Program to achieve better ozone results, reduce vehicle emissions, and meet federal air quality standards.
Check a vehicle against these quotes
Enter a model year, a fuel, and choose the county. The checker repeats the quotes above and, where a figure can be compared, says where your entry falls against it. It does not decide anything about your vehicle.
Which pages could we not read?
We ask for each page with a plain request that names this site, and we don’t work around a refusal. These pages matter for Colorado and did not open for us:
- Colorado Department of Public Health and Environment website (refused our reader on November 11, 2026)
- Colorado DMV website (refused our reader on November 11, 2026)
Where do these quotes come from?
- Colorado General Assembly, Emissions (legislative staff summary) (content.leg.colorado.gov; state legislature page; read November 11, 2026)
- Legislative Council Staff Issue Brief 17-23, Vehicle Emissions Testing in Colorado (content.leg.colorado.gov; state legislature page; read November 11, 2026)
- Air Care Colorado, FAQ: Quick Consumer Information (aircarecolorado.com; program site we treat as contractor-run, linked from Colorado General Assembly, Emissions (legislative staff summary); read November 11, 2026)
Spotted a quote that has changed at its source? Tell us. See also the comparison table for the other states.