Sales tax in Adams County, Colorado
There is no single sales tax rate in Adams County. It runs from 3.75% to 9.75% depending on the exact address, because cities and special districts inside the county levy their own on top of the 2.9% state rate. The 2.9% state rate applies everywhere in the county; everything above that depends on where you are standing. These rates were read from Colorado's own published schedule and checked on September 9, 2026. The rate in each of the 10 cities is in the table below.
What is the sales tax rate in Adams County?
| Colorado state rate | 2.9% |
|---|---|
| Adams County rate | 0.75% |
| Lowest combined rate in the county | 3.75% |
| Highest combined rate in the county | 9.75% |
The combined figures are the lowest and highest totals anywhere in Adams County, so the rows above do not add up to them.
What is the sales tax rate in each city in Adams County?
Colorado publishes the rate for every city it taxes. These are the combined rates, state and local together, as listed in Colorado's own rate file. Where a city shows a range, a special district covers only part of it, so the rate depends on the exact address.
| City | July 1 to December 31, 2026 |
|---|---|
| Arvada | 8.21% |
| AuroraThe rate depends on the address, from 7.5% to 8.5%: 7.5% with a 3.75% city tax and Scientific and Cultural Facilities District sales tax (0.1%); 8.5% with a 3.75% city tax, Regional Transportation District sales tax (1%) and Scientific and Cultural Facilities District sales tax (0.1%). | 7.5% to 8.5% |
| Bennett | 7.75% |
| Brighton | 8.5% |
| Commerce City | 9.75% |
| Federal Heights | 8.75% |
| Lochbuie | 8.75% |
| Northglenn | 8.75% |
| Thornton | 8.5% |
| Westminster | 9% |
| Unincorporated Adams CountyThe rate depends on the address, from 3.75% to 5.25%: 3.75% with Scientific and Cultural Facilities District sales tax (0.1%); 4.75% with Regional Transportation District sales tax (1%) and Scientific and Cultural Facilities District sales tax (0.1%); 5.25% with Regional Transportation District sales tax (1%), Scientific and Cultural Facilities District sales tax (0.1%) and Fire Protection District (0.5%). | 3.75% to 5.25% |
Source: Colorado rate file for July 1 to December 31, 2026, from Colorado's official rate page.
How much sales tax is that on a purchase in Adams County?
At 3.75%, a $100 purchase carries $3.75 in sales tax and a $1,000 purchase $37.50, at the lowest rate in the county. At the highest, 9.75%, the same purchases carry $9.75 and $97.50. That is general merchandise; Colorado taxes some categories, often groceries, differently, as the note below explains.
Among Colorado's 64 counties, Adams County's lowest rate ranks 53rd highest. See every Colorado county.
Sales tax in counties next to Adams County
Adams County borders 7 counties. The lowest rate next door is 2.9% in Morgan County, CO, which is $8.50 less on a $1,000 purchase than the lowest rate in Adams County.
| County | Combined sales tax |
|---|---|
| Denver County, CO | 9.15% |
| Broomfield County, CO | 7.15% to 8.35% |
| Jefferson County, CO | 4.5% to 8.75% |
| Washington County, CO | 4.4% to 6.9% |
| Adams County, CO (this county) | 3.75% to 9.75% |
| Arapahoe County, CO | 3.25% to 8.05% |
| Morgan County, CO | 2.9% to 7.9% |
| Weld County, CO | 2.9% to 8.4% |
Why the rate here is not the whole story
Colorado charges 2.9 percent statewide and then stacks a county rate, city rates and special district rates whose boundaries do not follow county lines, so a single rate for the whole county does not exist. The county itself levies 0.75 percent countywide. The floor of 3.75 percent is unincorporated county where the Scientific and Cultural Facilities District also applies. The ceiling of 9.75 percent is at Commerce City, on top of a fire protection district, the Regional Transportation District and the Scientific and Cultural Facilities District. That ceiling is set by a self collected home rule jurisdiction, which administers its own sales tax and can change it on a date the state file does not carry, so confirm it with the jurisdiction or the state lookup before charging it.
How do I find the exact rate for an address in Adams County?
Use Colorado's own address lookup. In Adams County the rate depends on the address, anywhere from 3.75% to 9.75%.
Who has to collect sales tax in Adams County?
Any seller with a physical presence in Colorado collects at the rate for the address of the sale; a remote seller does once it passes Colorado's economic nexus threshold. Colorado sales tax covers the statewide rules and what is exempt.
Work out your own numbers
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Sales tax calculator
Tax on a specific purchase at this county's rate, and the total you will actually pay.
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Do you have to collect?
Whether your sales into Colorado cross its economic nexus threshold. A different question from the rate.
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Property tax in Adams County
The other local tax: effective rate and median bill for this county.
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Sales tax by county
Every US county, and how Colorado compares with the rest of the country.
Sources
- Adams County rates: Colorado Department of Revenue, DR 1002 Colorado Sales/Use Tax Rates combined with DR 0800 jurisdiction codes, Colorado_Jurisdiction_Codes_Rates_July-Dec2026.xlsx, edition effective July 1 2026 through December 31 2026, https://tax.colorado.gov/sites/tax/files/documents/Colorado_Jurisdiction_Codes_Rates_July-Dec2026.xlsx
- Collected and verified September 9, 2026. Confidence: P on the rate components, S on the range (P read on a primary agency page, S strong but indirect, U unverified).