If your business makes taxable sales to customers in Colorado, you may need to register for a Colorado Sales Tax License before collecting sales tax. This 2026 guide explains who must register, what information you need, and how to complete the registration process through Revenue Online.
For broader information about Colorado sales tax rules, rates, and taxability, see the Colorado Sales Tax Guide. For details on filing deadlines and how to submit returns, see the Colorado Sales Tax Filing Guide.
Quick answers: Colorado sales tax registration
A quick overview of the authority, registration portal, nexus threshold, and other essentials for registering in Colorado.
| Fact | Detail |
|---|---|
| Authority | Colorado Department of Revenue |
| Registration portal | Revenue Online |
| Economic nexus threshold | $100,000 in annual sales into Colorado |
| Registration fee | Free |
| Renewal period | Annual renewal required by January 31 |
Who must register for Colorado sales tax
You must register for a Colorado Sales Tax License if your business has a sales tax nexus in the state. This usually applies when a business:
- Exceeds the economic nexus threshold of $100,000 in annual sales into Colorado in the current or previous calendar year, or;
- Has a physical presence in Colorado, such as an office, employee, warehouse, or inventory stored in the state.
Colorado's economic nexus threshold is based solely on dollar volume. Unlike many other states, Colorado does not impose a separate transaction count threshold. You only need to cross the $100,000 sales mark to trigger the registration obligation.
Once you exceed the threshold, you should register before making further taxable sales in Colorado. If you're unsure whether your business has nexus, see the Colorado Sales Tax Guide for a broader explanation.
Home Rule municipalities: an important Colorado-specific consideration
Colorado is unusual in that many of its cities and towns are Home Rule municipalities. These jurisdictions, which include Denver, Aurora, Boulder, Colorado Springs, and others, have the authority to administer and collect their own sales tax completely independently from the state.
Registering through Revenue Online covers state-level sales tax only. If you make sales into a Home Rule city, you will typically need to register separately with that municipality and file returns directly with it. Each Home Rule city sets its own rates, rules, and filing deadlines.
Before you begin selling into Colorado, check whether any of your customers are located in Home Rule jurisdictions and contact those cities directly about their registration requirements.
How to register for Colorado sales tax
Sellers can register online through Revenue Online, the Colorado Department of Revenue's self-service portal. This is the same portal you will use to file state-level returns and make payments after registration.
Information you need before registering
Before applying for a Colorado Sales Tax License, have this information ready:
- Your Social Security number (if registering as a sole proprietor with no employees)
- Your Employer Identification Number (EIN), if your business has one (required for corporations, partnerships, and most LLCs)
- North American Industry Classification System (NAICS) code for your primary business activity
- The date of your first sale in Colorado
- Your business address and any Colorado locations, if applicable
Registration steps
Follow these steps to register for a Colorado Sales Tax License.
1. Create your Revenue Online account
Set up your Revenue Online login credentials.
- Choose a username and password
- Set up your security information
- This login is used for all future state-level filings, payments, and account management
If you already have a Revenue Online account for another Colorado tax type, you can add a sales tax account to your existing login.
2. Provide your business information
Enter your business name, address, type of entity, and any Colorado locations.
- Remote sellers without a Colorado location should indicate they are selling remotely into the state
- Colorado uses destination-based sourcing for most sales, meaning you apply the rate for the buyer's location
- Be aware that combined rates vary significantly across the state due to state, county, municipal, and special district layers
3. Registration fee
There is no fee to register for a Colorado Sales Tax License. Registration through Revenue Online is free.
4. Submit your application
Review your entries and submit the application.
- You will receive an on-screen confirmation after submission
- A confirmation email is typically sent shortly after submission
5. Receive your Colorado Sales Tax License number
Once approved, you will receive:
- Your Colorado Sales Tax License number (used for state-level filing and payments)
- Your assigned filing frequency (monthly, quarterly, or annually, based on expected tax liability)
- Access to Revenue Online for filing, payment, and account management
What happens after registration
After registering, you must begin collecting Colorado sales tax on taxable sales and file returns based on your assigned filing frequency. Remember to also check your obligations with any Home Rule municipalities where you have customers, as those require separate registration and filing outside of Revenue Online.
Colorado's state sales tax rate is 2.9 percent, but the combined rate including local and special district taxes can be considerably higher depending on where your buyers are located.
For more detail on rates, taxability, and how local taxes interact with the state rate, see the Colorado Sales Tax Guide.
For information on filing frequencies, due dates, and how to submit your state returns, see the Colorado Sales Tax Filing Guide.
Note: At Quaderno we love providing helpful information and best practices about taxes, but we are not certified tax advisors. For further help, or if you are ever in doubt, please consult a professional tax advisor or the local tax authorities.
Need help registering across multiple states?
Watch our webinar: US Sales Tax Registration & Filing Tips + AMA. Learn how international sellers register, file, and manage US sales tax compliance across multiple jurisdictions.
Note: At Quaderno we love providing helpful information and best practices about taxes, but we are not certified tax advisors. For further help, or if you are ever in doubt, please consult a professional tax advisor or the tax authorities.
