The Boulder sales tax rate is 9.195% as of 2026, combining city, state, county, and regional district levies on most retail sales inside city limits. Boulder is a home-rule municipality, so it writes its own tax code, runs its own filing portal, and enforces collection independently of the Colorado Department of Revenue. If you sell into Boulder, you deal with Boulder directly.
How the 9.195% Breaks Down
Four layers stack to produce the total rate:
- City of Boulder: 3.86%, funding local services like public safety, parks, and transportation.
- State of Colorado: 2.9%, collected by the city on the state’s behalf.
- Boulder County: 1.335%, covering open space, affordable housing, wildfire mitigation, emergency services, transportation, and other voter-approved programs.
- RTD/CD/FD: 1.10%, supporting the Regional Transportation District and the Scientific and Cultural Facilities District.
The county portion rose from 1.185% to 1.335% on January 1, 2026, after voters approved a new mental and behavioral health tax.1Boulder County. Sales and Use Tax Any point-of-sale system programmed before 2026 needs updating to reflect the new combined rate.2City of Boulder. Tax Rates and Types
What Boulder Taxes
Sales tax applies to the sale or lease of tangible personal property, which covers clothing, electronics, furniture, and the rest of the obvious physical goods. Certain services are taxable too, including telecommunications and the delivery of gas or electric utilities. Leases, rentals, and license agreements for tangible property or taxable services also trigger the tax.
The category that catches sellers off guard is software and digital products. Boulder’s code defines “computer software” to include digital products, software programs, software-as-a-service, internet subscription services, software license fees, and maintenance agreements. Downloadable music, streaming access, a SaaS subscription, software on a disc: all taxable. Custom software built entirely for a single user is the main exception.3City of Boulder. Tax Compliance Guides
What’s Exempt
Boulder exempts several categories tied to basic needs:
- Food for home consumption. Prepared food sold at restaurants remains fully taxable.
- Prescription drugs dispensed with a valid prescription bearing the “Rx Only” symbol, under Boulder Revised Code section 3-1-1.
- Medical supplies like wheelchairs, prosthetic devices, hearing aids, corrective lenses, insulin, and oxygen, when dispensed for an individual’s direct personal use under a prescription. The item must be separately stated and billed to the patient or insurer; otherwise the city treats the provider as having consumed it.3City of Boulder. Tax Compliance Guides
Boulder County separately exempts food for home consumption, residential gas and electricity, machinery and machine tools, renewable energy components, diapers, and period products.4Colorado Department of Revenue. Sales Tax Rate Changes Keep detailed records of every exempt sale. The city audits for compliance and will assess penalties on improperly claimed exemptions.
Lodging Carries an Extra Tax
Hotels, motels, short-term rentals, and other lodging inside city limits pay an additional 7.50% accommodation tax on top of the standard components. Combined with the state, county, and RTD portions, the total tax on a night’s lodging in Boulder reaches 12.835%.2City of Boulder. Tax Rates and Types
If you list a property on Airbnb, Vrbo, or similar platforms, you are responsible for collecting and remitting this tax unless the platform handles it. Verify what the platform actually collects. Many only handle state-level taxes automatically and leave the Boulder-specific pieces to you.
Use Tax When the Seller Didn’t Charge
If you buy something for use in Boulder and the seller didn’t collect Boulder’s sales tax, you owe use tax at the same 3.86% city rate. This applies to both businesses and residents. Common triggers include out-of-state online purchases from sellers who don’t collect Boulder tax, items pulled from wholesale inventory for business use rather than resale, and purchases from vendors who simply failed to charge the right amount.5City of Boulder. Use Tax
Businesses report use tax as part of their regular sales tax return through the Boulder Online Tax System. Individuals can file a separate consumer use tax return through the same portal. This is the obligation most people overlook, and it’s where auditors tend to find money on the table.
Getting a License and Filing Returns
Before your first retail sale in Boulder, you need a business license from the city’s Finance Department authorizing you to collect and remit sales tax. Apply through the Boulder Online Tax System. The city asks for your FEIN (or Social Security Number for sole proprietors), legal and DBA names, NAICS code, physical addresses for every Boulder location, a mailing address, and the exact date operations began in the city.6City of Boulder. Boulder Online Tax System Help Center
All returns go through the same portal. Enter gross sales, subtract exempt transactions, and the system calculates the tax based on current rates. Filing frequency depends on how much tax you collect:
- Monthly, if your average tax due is $300 or more per month. Returns are due by the 20th of the following month.
- Quarterly, if your average is between $15 and $300 per month.
- Annual, if your average is under $15 per month.
When a due date falls on a weekend or holiday, it shifts to the next business day.7City of Boulder. Sales and Use Tax Pay by ACH bank transfer or credit card through the portal. Credit card payments often carry processing fees. Late filing triggers penalties and interest.2City of Boulder. Tax Rates and Types
Selling Into Boulder From Outside
You don’t need a storefront in Boulder to owe tax there. Two rules reach outside sellers.
Marketplace facilitators, meaning platforms like Amazon or Etsy where third parties list products, must collect and remit Boulder sales tax on sales made through the platform to Boulder customers. If you sell only through such a platform, the platform carries the legal responsibility. If you also sell through your own website or a physical store, you still need your own Boulder business license and must file returns for those non-marketplace sales.8City of Boulder. Marketplace Facilitator Guide
Remote sellers who exceed $100,000 in annual gross sales into Colorado must register with Boulder and collect its tax. The threshold counts all retail sales of tangible personal property, commodities, and services delivered into the state, not just sales into Boulder. If you cross the threshold in the prior calendar year, you must be registered and collecting by January 1. If you cross it mid-year, you have 90 days after the month in which you exceeded it before collection kicks in.9City of Boulder. Guidance for Remote Sellers
Records and Audits
Boulder can audit your filings, and when it does, the city expects complete transaction records behind every return: sales receipts, exemption certificates, purchase invoices for use tax purposes, and copies of filed returns. Most tax professionals recommend keeping these for at least seven years. If you never file a return for a period in which you owed tax, there is generally no time limit on when the city can come looking. The statute of limitations clock does not start until a return is actually filed.
Reconcile your sales tax filings with your accounting records each period before you submit. Errors caught at filing are free to fix. Errors caught during an audit come with penalties and interest attached.