Boulder County collects sales & use tax on retail sales as well as county building permits and motor vehicle registration by applying the voter-approved tax rate as follows:
Boulder County Tax Rates
Boulder County tax rates are updated annually, and published in January.| Rate | Resolution | Expiration |
|---|---|---|
| 0.065% | Transportation Improvements | Perpetuity |
| 0.035% | Transportation Improvements - Trails | Perpetuity |
| 0.185% | Alternative Sentencing | 12/31/2024 |
| 0.050% | Jail Improvements & Operations | Perpetuity |
| 0.050% | Human Services - Worthy Cause | 12/31/2033 |
| 0.125% | Open Space Capital Improvements 1994 | 12/31/2034 |
| 0.100% | Open Space Capital Improvements 2005 | 12/31/2024 |
| 0.100% | Open Space Capital Improvements 2008 | 12/31/2029 |
| 0.150% | Open Space Capital Improvements 2011 | 12/31/2030 |
| 0.125% | Sustainability | 12/31/2034 |
| 0.100% | Wildfire Mitigation | Perpetuity |
| 0.100% | Emergency Services | 12/31/2027 |
| 1.185% | Total Boulder County Tax Rate |
Tax District Rates
The following table provides the rates across tax districts within Boulder County. This chart is provided as a courtesy: please direct questions regarding city sales taxes to the appropriate city’s administrative office. **RTD = Regional Transportation District; SCFD = Scientific and Cultural Facilities District.| City/Area | Municipal District | Special District | State | RTD/SCFD | Boulder County | Total Rate |
|---|---|---|---|---|---|---|
| Boulder | 3.86% | - | 2.90% | 1.10% | 1.185% | 9.045% |
| Boulder Food Service | 4.01% | - | 2.90% | 1.10% | 1.185% | 9.195% |
| Erie | 3.50% | - | 2.90% | 1.10% | 1.185% | 8.685% |
| Lafayette | 3.87% | - | 2.90% | 1.10% | 1.185% | 9.055% |
| Longmont | 3.53% | - | 2.90% | 1.10% | 1.185% | 8.715% |
| Louisville | 3.775% | - | 2.90% | 1.10% | 1.185% | 8.960% |
| Lyons | 3.50% | - | 2.90% | 1.10% | 1.185% | 8.685% |
| Nederland | 4.25% | - | 2.90% | 1.10% | 1.185% | 9.435% |
| Niwot | - | - | 2.90% | 1.10% | 1.185% | 5.185% |
| Niwot Local Improvement District | - | 1.00% | 2.90% | 1.10% | 1.185% | 6.185% |
| Superior | 3.46% | - | 2.90% | 1.10% | 1.185% | 8.645% |
| Ward | 2.00% | - | 2.90% | 1.10% | 1.185% | 7.185% |
| Unincorporated Boulder County | - | - | 2.90% | 1.10% | 1.185% | 5.185% |
Colorado Department of Revenue, Sales Tax Division – 303-238-7378
Sales Tax
Boulder County’s Sales Tax Rate is 1.185% for 2024
Sales tax is due on all retail transactions in addition to any applicable city and state taxes.
Boulder County does not issue licenses for sales tax as the county sales tax is collected by the Colorado Department of Revenue (CDOR). Businesses register with CDOR to determine what taxes to pay. CDOR collects the sales tax from business on behalf of Boulder County.
All payments of Boulder County sales tax should be reported through CDOR’s Revenue Online service, or by using their printable forms.
Returns Information
- Sales tax returns are due the 20th of the month following the month reported. If the 20th falls on a holiday or a weekend, the due date is the next business day. Returns must be postmarked on or before the due date to be considered on time.
- A tax return must be filed even if there is no tax due.
- Sales tax accounting records must be retained by the collecting entity for three years from the date of filing and paying a return.
- For exemption information, please consult CDOR’S Tax Exemption Qualifications page.
NOTE: Boulder County taxes are collected by the State of Colorado. All payments of sales tax should be reported and remitted directly to the Colorado Department of Revenue. Forms and additional details are available at Revenue Online or by contacting the Colorado Sales Tax Office via their Taxpayer Hotline, at 303-238-7378.
Use Tax
Boulder County collects Use Tax at a rate of 1.185% in 2024. Use tax is levied in the following circumstances:
- Motor Vehicles: Storing, using, or consuming in Boulder County any motor or other vehicle, purchased at retail on which a registration is required. This tax is collected at vehicle registration with the Boulder County Clerk & Recorder’s Office, Motor Vehicle Division.
- Building and Construction Materials: Applies to building and construction materials purchased in or delivered to Boulder County at retail. This tax is collected when a building permit is obtained for unincorporated Boulder County or the Town of Jamestown. By intergovernmental agreement, the tax is also collected by the municipal building departments in Boulder, Lafayette, Longmont, Louisville, Lyons, Erie, Superior, and Nederland.Performing construction work in Boulder County requires a building permit and the permit includes a use tax payment to the county (either directly to Boulder County or to the municipality that issues the permit). The cost of the building permit is a prepayment deposit of an estimated use tax. At the end of the project a reconciliation of estimated construction material costs and actual construction material costs may be requested to verify the use tax accuracy. The difference between the estimated tax and actual tax due is based on actual project cost. Building materials purchased in or delivered to Boulder County for a permitted project are exempt from the retail sales tax so contractors are encouraged to present the county building permit at the time of purchase. Contractors should keep all invoices and statements of construction materials from general contractors, subcontractors, and suppliers, along with a summary sheet showing such purchases for three years from the date of issuance of the certificate of occupancy. Please see the Boulder County Building Permits page for further information.
Boulder County Brochures
A concise annually-updated guide for Boulder County merchants who collect and file sales tax.
| 2024 S&UT Brochure | 2023 S&UT Brochure | 2022 S&UT Brochure | 2021 S&UT Brochure | 2020 S&UT Brochure |
Additional Resources
- Colorado Department of Revenue – Sales Tax Accounts and Licenses – CDOR site with information covering all aspects of sales tax.
- Verify Sales Tax License or Tax-Exempt Certificate – Colorado Department of Revenue site where vendors’ sales tax licenses and tax exemption certificate can be verified.
- Colorado Taxpayer Hotline – current phone number: 303-238-7378