Colorado keeps formation about as cheap and fast as it gets, filed entirely online with same-day approval. The one wrinkle is sales tax: Colorado is a "home rule" state, so cities like Denver and Boulder run their own separate tax systems instead of just riding on top of the state's. Here's what it takes to start a business in Colorado in 2026.
1. Which business structure fits you?
Before you file anything, it helps to know what you're actually choosing between.
- Sole proprietorship. No filing required to start, and you and the business are legally the same entity. Simple, but you're personally liable for whatever the business owes.
- Partnership. Two or more people running a business together, with the same liability exposure as a sole proprietorship, just split across partners.
- LLC. The most common structure for small businesses in Colorado. It separates your personal assets from the business's debts and lawsuits.
- Corporation, either S-corp or C-corp. More paperwork and more formality, usually worth it once you're bringing on investors or multiple shareholders.
For a deeper comparison, see our guide on choosing a business structure.
LLCs and corporations register with the Colorado Secretary of State, the agency that handles business filings statewide. Sole proprietorships and general partnerships don't register there.
2. Register your business
Forming an LLC
You form an LLC in Colorado by filing Articles of Organization with the Secretary of State. The filing fee is $50, and Colorado only accepts online filings, so approval is typically instant once payment clears.
Every LLC needs a registered agent with a physical Colorado address, available during business hours. You can act as your own agent, or hire a commercial service.
Colorado doesn't require an operating agreement by law, but it's still worth writing one, particularly for multi-member LLCs, to spell out how decisions and profits get split.
Sole proprietorships and DBAs
Sole proprietorships don't file with the Secretary of State. If you're operating under a trade name, you'll register a Statement of Trade Name directly with the Secretary of State, which in Colorado is a state-level filing rather than a county one.
3. Get an EIN
An Employer Identification Number is free straight from the IRS and takes about 15 minutes online. You'll need one to open a business bank account, hire anyone, or file most business tax forms, even if you're a single-member LLC with no employees.
4. Check licenses and permits
Colorado doesn't issue a single general statewide business license either. What you need depends on your industry and city: professional licensing for regulated fields, a local business license in some cities, and sales tax registration if you sell taxable goods or services. That last one gets more complicated in Colorado than most states, since roughly 70 home-rule cities, including Denver, Aurora, Boulder, and Colorado Springs, administer their own sales tax separately and require their own registration. Our guides on professional licensing by industry and zoning laws for home businesses cover more on the licensing side.
5. Understand Colorado taxes
Colorado has a flat personal income tax rate of 4.4%. Pass-through LLCs owe no separate franchise tax; members just pay this flat rate on their share of profits.
Sales tax starts at a 2.9% state base, one of the lowest in the country, but that number is misleading on its own. Counties, cities, and special districts stack additional taxes on top, and in home-rule cities the local government collects and audits separately from the state. Combined rates commonly land between 7% and 9%, and can exceed 11% in places like Aspen.
6. Stay compliant
Every Colorado LLC files a Periodic Report with the Secretary of State once a year, due during your anniversary month. The fee is $25. Miss it and you'll owe a $50 delinquency fee; the state emails a reminder when your filing window opens.
Colorado business costs at a glance
| Item | Cost |
|---|---|
| Articles of Organization (LLC) | $50 |
| Periodic Report (every year) | $25 |
| Late delinquency fee | $50 |
| Registered agent service (optional) | $100 to $200/year |
| EIN | Free (IRS) |
| State income tax | 4.4% flat |
| State sales tax | 2.9% + local (home-rule cities separate), up to ~11% |
Frequently asked questions
Why is sales tax more complicated in Colorado than most states?
Colorado is a "home rule" state, so roughly 70 cities, including Denver, Aurora, Boulder, and Colorado Springs, administer their own sales tax separately from the state and require their own registration.
How much does it cost to form an LLC in Colorado?
$50 for Articles of Organization, filed entirely online with typically instant approval.
How often do Colorado LLCs file reports?
Annually. The Periodic Report is due during your anniversary month for $25, with a $50 delinquency fee if missed.
What's the personal income tax rate in Colorado?
A flat 4.4%.
How high is sales tax in Colorado?
A 2.9% state base, but combined rates commonly land between 7% and 9%, exceeding 11% in places like Aspen.
Fees and rates above come from the Colorado Secretary of State and Department of Revenue as of 2026, and they do change over time, so double check before you file. None of this is legal or tax advice. Talk to a Colorado-licensed attorney or CPA about your specific situation.