Colorado Sales Tax and Invoicing Rules for 2026

TL;DR: Colorado has a low 2.9% state sales tax but local additions create combined rates of 4.0%–11.2%. Colorado has one of the most complex local tax systems in the U.S. — many cities are "home rule" and administer their own sales tax. Economic nexus applies at $100,000 in annual sales.

State sales tax rate

Colorado imposes a 2.9% state sales tax — one of the lowest state rates in the country. However, counties, cities, and special districts layer on additional taxes that push combined rates to 4.0%–11.2%.

Denver's combined rate is approximately 8.81%. Colorado Springs is around 8.25%. Boulder reaches about 9.05%.

The complexity arises from home rule cities — over 70 Colorado cities administer their own sales tax independently, separate from the state system. This means you may need to register, file, and remit with individual cities in addition to the state.

Colorado uses destination-based sourcing.

Nexus rules

Physical nexus applies through offices, employees, inventory, or property in Colorado.

Economic nexus triggers at $100,000 in gross sales into Colorado in the current or prior calendar year. There is no transaction count threshold.

Critically, home rule cities may have their own economic nexus thresholds — Denver, for example, has its own $500,000 threshold for remote sellers. Marketplace facilitators must collect state sales tax on behalf of third-party sellers, but home rule city obligations may vary.

Colorado's system is evolving — the Sales and Use Tax System (SUTS) is a voluntary filing portal that simplifies multi-jurisdiction compliance.

Invoice requirements

The Colorado Department of Revenue requires sellers to maintain records of all transactions. Invoices should include:

• Seller's name, address, and Colorado account number
• Date of sale
• Buyer details
• Description of items
• Sale price
• State, county, city, and special district tax rates (ideally broken out)
• Total tax and total due

Because of the many overlapping jurisdictions, detailed records of the delivery address and applicable rates are essential. For exempt sales, retain the buyer's Colorado Exemption Certificate (Form DR 0563). Records should be kept for at least three years.

Exemptions and special cases

Groceries (food for home consumption) are exempt from state sales tax but may be taxed by local jurisdictions — some cities exempt groceries, others do not.

Prescription drugs are exempt. Machinery used in manufacturing, mining, and agriculture is exempt. Clothing is fully taxable.

SaaS and digital goods are generally not taxable at the state level — Colorado taxes tangible personal property and has not broadly classified cloud services as taxable. However, some home rule cities tax different categories than the state does.

Retail delivery fees apply — Colorado enacted a retail delivery fee (separate from sales tax) on delivered goods that must be listed as a separate line item on invoices.

Filing frequency and deadlines

State returns are filed based on liability:

• Monthly — liability over $300/month
• Quarterly — between $15 and $300/month
• Annually — under $15/month

Monthly returns are due the 20th of the following month. Quarterly returns are due April 20, July 20, October 20, and January 20. Annual returns are due April 15.

Home rule cities have their own filing calendars — Denver, Aurora, Lakewood, and others may have different due dates. The SUTS portal allows combined state and participating local filings to reduce complexity.

Penalties for non-compliance

Late filing incurs a 10% penalty on unpaid state tax (minimum $15) plus 0.5% per month up to 18%. Interest accrues at the prime rate plus 3%.

Home rule cities impose their own penalties. Failure to register with both the state and applicable home rule cities can result in multiple back-assessments. Colorado has been expanding enforcement, particularly targeting remote sellers.

FAQ

What are home rule cities and why do they matter?

Over 70 Colorado cities administer their own sales tax independently from the state. You may need separate registrations, separate returns, and separate remittance for each home rule city where you have nexus. The SUTS portal is helping reduce this burden.

Are groceries really tax-free in Colorado?

Groceries are exempt from the 2.9% state sales tax. However, many local jurisdictions still tax food for home consumption. The actual tax on groceries depends on where the buyer is located.

What is the retail delivery fee?

Colorado enacted a retail delivery fee on deliveries of tangible personal property. This is a separate charge from sales tax and must be listed as a separate line item on invoices. The fee amount adjusts annually — check the Department of Revenue for the current amount.

Use InvoiceQuickly's tax rate lookup to find the right combined rate for Colorado's complex jurisdictions.