Overview: When starting a business with employees in Colorado, you’ll need to register with multiple agencies for payroll compliance. Employers must set up accounts for Withholding Tax with the Department of Revenue (DOR), State Unemployment Insurance (SUI) Tax with the Department of Labor & Employment (CDLE), and Family and Medical Leave Insurance (FAMLI). In addition, some municipalities require Occupational Privilege Taxes (OPT), which must be registered at the local level.
Important! This guide does not constitute legal or tax advice. You can consult a CPA or attorney for official guidance.
Taxes You Must Register For:
Colorado Withholding Tax
Tax Agency: Colorado Department of Revenue
Registration Steps:
1. Register for a Withholding Tax Account
If located in Colorado: Register online via MyBizColorado.
If located outside Colorado: Complete and submit Form CR 0100 (Sections A, B, D, E, F, and G).
Processing Time: Account number assigned immediately via MyBizColorado or within 4–6 weeks for mailed form.
Colorado Unemployment Insurance (UI) Tax
Tax Agency: Colorado Department of Labor & Employment (CDLE)
Registration Steps:
1. Register for a UI Account Number
Register online at MyBizColorado or submit Form UITL-100.
2. Assign Third-Party Access (TPA) to Check
Log in to MyUIEmployer+.
Navigate to: Account Maintenance > Third Party Administrator Authorization
TPA ID: 500003641
Assign start date (must be first day of quarter: e.g., 01/01/YYYY).
Assign the following roles:
View Account Maintenance
Submit Employment and Wage Detail
View Rate Notice and Voluntary Contribution
Edit Tax Payments Update and Submit
Save changes.
Colorado Family and Medical Leave Insurance (FAMLI)
Tax Agency: Colorado FAMLI Division (CDLE)
Registration Steps:
1. Register for a FAMLI Account
Click “Log into My FAMLI+ Employer”
Select “Create an account” via login.gov
Complete email verification, password setup, and authentication
Proceed with registration
2. Assign TPA Access
Log into My FAMLI+ Employer Portal
Navigate to: Manage My Accounts > Manage Accounts
Scroll to Third-Party Administrator section
Search for and select “Check Technologies, Inc.”
TPA FEIN: 834490700
Enter start date (first day of quarter) and confirm
Colorado Occupational Privilege Taxes (OPT)
Some Colorado municipalities impose OPT. Registration is required at the city level if you operate in these jurisdictions. Examples include:
Aurora
Register online through the Aurora Tax Portal
$17 application fee
Denver
Register online or complete paper application
Glendale
Register online or submit paper application
$10 registration fee
Greenwood Village
Submit license application
Sheridan
Update Your Account
Be sure to update your account with:
Colorado Withholding Tax Account Number
UI Account Number
FAMLI Account Number
Any applicable local OPT account numbers
All numbers are necessary for timely and accurate payroll tax filings.