Sales tax in Boulder, CO
The combined sales tax rate in Boulder, CO is 9.195%, effective 2026-07-01.
Last verified
- ZIP codes
- 7 on file · 1 wholly inside the city limits
- County
- Boulder County
- Levied by
- Colorado and Boulder
How the combined rate in Boulder, CO is made up
Each government below levies its own share. A seller collects them together at the till and passes each share to the authority that levied it.
| Jurisdiction | Type | Rate | Effective | Source |
|---|---|---|---|---|
| Colorado | state | 2.9% | Jan 1, 2001 | Colorado jurisdiction codes and rates |
| Boulder | city | 6.295% | Jul 1, 2026 | Colorado jurisdiction codes and rates |
| Combined rate | 9.195% | |||
ZIP codes in Boulder
7 on file — 1 wholly inside the city limits and 6 crossing them. Each has its own page.
1 ZIP code wholly inside Boulder
Every address in these is inside the city limits, so all of them pay Boulder's rate.
| ZIP code | Combined rate | Also reaches |
|---|---|---|
| 80310 | ~9.195% | no other city |
6 ZIP codes crossing the city line
Part of each of these lies outside Boulder. An address in one may be taxed at a neighbour's rate instead, and the figure shown is the most likely one across the whole ZIP code.
| ZIP code | Combined rate | Also reaches |
|---|---|---|
| 80301 | ~9.195% | no other city |
| 80302 | ~9.195% | no other city |
| 80303 | ~9.195% (9.11%–9.195%) | Louisville |
| 80304 | ~9.195% | no other city |
| 80305 | ~9.195% | no other city |
| 80503 | ~9.335% (6.335%–9.335%) | Longmont, Lyons and Niwot |
What can change the tax you pay in Boulder, CO
- ZIP codes shared with a neighbour. 2 of Boulder's 7 ZIP codes are also reached by Longmont, Louisville, Lyons and Niwot, so an address in one of them can owe a neighbour's rate instead of Boulder's.
- What you are buying. Categories are not taxed alike. The calculator switches between general merchandise, prepared food and lodging, which are the categories we hold rates for here.
How Boulder compares with the rest of Colorado
Boulder's 9.195% is above what most ZIP codes carry in Colorado. Of the state's 641 ZIP codes with a figure, 9 land on the same one, 572 carry a lower figure and 60 a higher one. Across Colorado the combined rate runs from 2.9% to 11.2%. See every city in Colorado.
| Combined rate | ZIP codes | Which is this city |
|---|---|---|
| ~9.15% | 60 | |
| ~8.2% | 50 | |
| ~7.9% | 32 | |
| ~4.9% | 30 | |
| ~6.9% | 25 | |
| ~9.195% | 9 | Boulder |
Counted from ZIP-code figures. A tilde marks a band where some ZIP codes cross a tax boundary and are counted at their most likely rate.
How sales tax is collected
The seller generally collects the tax from the buyer at the point of sale and passes it to the authorities that levied it. In most states it is added at the till rather than included in the advertised price. Read how sales tax works, including sourcing rules, online purchases and who is required to collect.
Rates last verified: Sep 4, 2026. This is when the source was last read, not when this page was last edited.
TaxAndTips provides informational estimates from published tax-rate data. Actual tax treatment can depend on the product or service, the exact address, the transaction, exemption status and applicable law. For official obligations, consult the taxing authority or a qualified tax professional.
Why you can rely on these figures
- Published rates
- State and local rates compiled from the tax authorities that levy them.
- Every figure sourced
- See the jurisdiction breakdown and the document each rate came from.
- No signup
- Use the calculator immediately. Nothing to create, nothing to install.
- Missing means missing
- Where a rate is not verified we say so instead of showing a short total.