Hi, Mrs.mitchell0985. There are two reasons why QuickBooks adds Colorado to your Tax agencies. One reason is that you ship or perform services at your customer's address in Colorado, and the other reason is that you accidentally created a state tax agency. To remove this, we can make it Inactive in your Sales Tax Settings.
Here's how:
Open your QuickBooks.
Go to My Apps, then Sales Tax.
Head to Sales Tax Settings.
Under Actions, click the dropdown and select Make Inactive.