Colorado Sales Tax Guide (2026)

Colorado's state sales tax rate is 2.9% — the lowest state rate in the US — but county, city, and special-district taxes push combined rates above 9%. Denver's combined rate is about 9.15%. Roughly 70 home-rule cities administer their own sales tax and require separate registration and filing on top of the state.

Combined rates in major Colorado cities (2026):

To find the combined rate for a specific address, use our US sales tax calculator.

Colorado economic nexus applies once your sales into the state exceed $100,000 in the current or prior calendar year. There is no transaction-count trigger. Physical presence creates nexus immediately. State-collected jurisdictions are handled through the Department of Revenue, but home-rule cities require separate registration and returns.

Colorado's marketplace-facilitator collection requirement took effect October 1, 2019, under HB 19-1240. A marketplace facilitator must collect and remit all applicable Colorado state and state-administered local sales taxes on sales made in Colorado through its marketplace, taking on the rights, obligations, and liabilities of a retailer for those facilitated sales; a facilitator with no physical presence in Colorado is exempt only while its combined direct and facilitated Colorado sales stay under $100,000 in both the current and previous calendar year, the same threshold Colorado uses for its general remote-seller economic nexus. A marketplace seller is not required to collect state sales tax on sales made through a facilitator, and can document that relief with Form DR 1290 (Certification of Registered Marketplace Facilitator) or an explicit contract provision, though it remains responsible for tax on sales made through its own website or store.[10]

For state-collected jurisdictions, Colorado returns are due the 20th of the month following the reporting period and are filed through SUTS. Home-rule cities set their own deadlines and require separate returns, which is the biggest compliance burden in the state.

Colorado exempts groceries and prescription drugs at the state level, though home-rule cities may tax groceries. SaaS is not taxable at the state level, but some home-rule cities — including Denver — tax software and SaaS, so check each city where you have nexus.

Colorado retailers buying for resale use their state sales tax license number as a resale certificate, or the Colorado exemption certificate (DR 0563) or a multistate certificate [6]. The buyer gives it to the seller at purchase rather than filing it with the state, and the underlying sales tax license must be renewed each two-year cycle to stay valid [6].

Late filing or payment carries a penalty of the greater of $15 or 10% of the tax due, plus an additional 0.5% per month and interest from the due date.

A taxpayer must file a written protest of a Notice of Deficiency or a rejected refund within 30 days of the notice's mailing date, a deadline the Department cannot extend [7]. Protests go first to the Tax Conferee Section for an informal conference, then to a formal hearing, with further appeal to district court [7].

• [1] Colorado DOR — Sales 4 (state rate, food exemption)

• [2] Colorado DOR — Out-of-State Businesses (economic nexus, home-rule)

• [3] Colorado DOR — Computer Software (SaaS not taxed at state level)

• [4] Colorado General Assembly — HB 26-1223 (software taxable from Jan 1, 2027)

• [5] Colorado DOR — Sales Tax Guide (digital goods taxable)

• [6] Colorado DOR — Certificates of Exemption

• [7] Colorado DOR — Protest Rights (30 days)

• [8] Colorado General Assembly — HB 26-1048 (2027-2029 sales tax holiday)

• [9] Colorado DOR — Standard Retail License

• [10] Colorado Department of Revenue — Sales Tax Responsibilities of Marketplace Facilitators

Verified July 2026 against Colorado Department of Revenue published guidance.

• Colorado Clothing Sales Tax: A Complete Guide for Businesses