How Do I Get a Colorado State Tax ID Number? CR 0100 and Fees

To get a Colorado state tax ID number, submit the Sales Tax and Withholding Account Application (Form CR 0100) through the MyBizColorado online portal or by mailing the paper form to the Colorado Department of Revenue. The number you receive is called a Colorado Account Number, or CAN, and it becomes your permanent identifier for state sales tax, withholding, and any other state tax obligations tied to your business. Online applications are the fastest route; paper filings take four to six weeks to process.¹

The CAN is separate from your federal EIN, your Social Security Number, or an ITIN. It appears as the first eight digits of the Use Account Number printed on your sales tax license.²

Who Needs One

Any business making retail sales in Colorado needs a sales tax license, and the license comes with a CAN. If you have employees working in the state, you also need a withholding tax account, which attaches to the same number. Many businesses need both. The CR 0100 lets you open a sales tax account, a withholding account, or both at the same time.¹

Out-of-state sellers with no physical presence in Colorado still have to register once their annual sales into the state reach or exceed $100,000 in the current or previous calendar year. All retail sales count toward that threshold, including sales that would otherwise be exempt from Colorado tax. After you cross $100,000 in the current year, you have until the first day of the first month that starts at least 90 days later to get licensed and begin collecting. If you crossed it in the previous year, you owe collection from day one of the current year.³

What to Gather Before You Apply

Have these ready before you open the form:

Your federal EIN, or an SSN or ITIN if you’re a sole proprietor without employees.
Your legal business name and entity type (sole proprietorship, LLC, corporation, partnership, or other), matching the name on file with the Colorado Secretary of State where applicable.
Names, addresses, and identification numbers for every owner, partner, or corporate officer.
The six-digit NAICS code that describes your primary business activity.
Your business start date in Colorado.
The physical location where the business operates and a mailing address for Department correspondence.

If your business is an LLC, corporation, or partnership, register the entity with the Colorado Secretary of State before you apply for the tax account. Sole proprietors operating under their own legal name can go straight to the CR 0100.

What the CR 0100 Asks You

The CR 0100 is a single form that handles a sales tax license, a withholding account, or both, and it’s also what you use to add a new physical location to an existing account.⁴ You only fill in the sections that apply to you.

On the sales tax side, you’ll indicate whether you’re a retailer, a wholesaler, or a charitable organization. Retailers sell to end consumers and collect sales tax. Wholesalers sell to other retailers for resale; if a wholesaler also makes regular retail sales, it needs a retail license too.¹

On the withholding side, you’ll pick the type of payments you make: W-2 wages, 1099 payments, W-2G gambling winnings, or oil and gas withholding. One thing to know up front: 1099 and W-2G withholding accounts can only be opened by mailing the paper CR 0100. The online portal doesn’t handle those.⁵

The form also asks you to estimate your monthly sales tax collections and annual withholding. Those estimates decide how often you’ll file returns. Be realistic. If your actual collections consistently exceed your projected bracket, the Department will move you to a more frequent filing schedule.⁶

Fees

A new sales tax license costs $16 in fees plus a $50 refundable deposit, for $66 upfront per location.⁷ Every physical location needs its own license and its own fee. The $50 deposit is applied against any outstanding tax liability when you eventually close the account. There’s no fee to open a withholding-only account.

How to Submit

You have two paths.

The faster one is MyBizColorado, the state’s official online filing portal.⁸ You create a secure account, enter the CR 0100 information on screen, and pay the fee and deposit with a credit card or electronic check. Online applicants receive an account number quickly, though processing times vary.

To apply by mail, print the CR 0100 from the Department of Revenue website, complete it, and send it to the address on the form with a check or money order. Paper applications take four to six weeks.¹ Mail is also the only route if you need a 1099 or W-2G withholding account.⁵

The State License Doesn’t Cover Home Rule Cities

Your Colorado state sales tax license does not automatically authorize you to sell in every local jurisdiction. Colorado has dozens of home rule cities that collect their own sales and use taxes, set their own rates, decide their own rules on what’s taxable, and run their own licensing. Denver, Colorado Springs, and Aurora are among the largest. If you operate in or sell into a home rule city, you’ll likely need a separate license from that city’s tax or finance office in addition to the state one.⁹ This is the step new business owners most often miss.

Penalties for Skipping Registration

A retailer making sales without a valid license faces a civil penalty of $50 per day, up to a $1,000 maximum. The penalty can be waived if the failure was due to reasonable cause rather than willful neglect.¹⁰

On the employer side, if you should have withheld tax from wages and didn’t, you’re liable for the amount that should have been withheld, whether or not the employee later pays it directly. Filing false or late employee withholding statements adds a penalty of $5 to $50 per occurrence at the Department’s discretion.¹¹

After You Have Your Number

Keep the sales tax license certificate in both digital and physical form and display it at your place of business. Your CAN stays with the business for its operational life in Colorado, and you’ll use it for every filing, every piece of Department correspondence, and to set up a Revenue Online account for filing returns electronically.²

Keep your account information current. Address changes, ownership changes, and new locations all need updates. Adding a new physical location means filing another CR 0100 with another $16 fee and $50 deposit for that location.⁴

Colorado sales tax licenses run on a two-year cycle. The current period began January 1, 2026, and renewal costs $16 per location.¹² A missed renewal puts your license into expired status and can trigger the same penalties as operating without one.

If you stop doing business in Colorado, close the account within 30 days. File any outstanding returns (or zero-balance returns if you had no taxable sales), mark the final return as closing, and enter the last day of operations.¹³ Leaving the account open after you’ve stopped operating generates delinquent filing notices and avoidable penalties.

1
Colorado Department of Revenue. CR 0100 Colorado Sales Tax and Withholding Account Application
2
Department of Revenue – Taxation. How to Look Up a Colorado Account Number (CAN)
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Department of Revenue – Taxation. Sales Tax Guide
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Department of Revenue – Taxation. CR 0100 – Colorado Sales Tax and Withholding Account Application
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Department of Revenue – Taxation. Withholding Accounts – Account Set-Up and Changes
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Department of Revenue – Taxation. Sales Tax Filing Information
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Justia. Colorado Revised Statutes Title 39-26-103 – Licenses – Fee – Revocation – Definition
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Colorado.gov. MyBizColorado
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Department of Revenue – Taxation. Local Government Sales Tax
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Justia. Colorado Revised Statutes 39-26-103 – Licenses – Fee – Revocation – Definition
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Justia. Colorado Revised Statutes 39-22-604 – Withholding Tax – Requirement to Withhold – Tax Lien – Exemption From Lien – Definitions
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Department of Revenue – Taxation. Renew Your Sales Tax License
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Department of Revenue – Taxation. Close Sales Tax Account