Overview

Yes, short-term rentals are explicitly allowed in Thornton, CO. The City Council approved Ordinance No. 2020-099 on July 15, 2020, which went into effect on February 1, 2021, legalizing short-term rentals under specific conditions and requirements. Thornton has established a comprehensive regulatory framework that allows STRs as an accessory use to an owner's primary residence while implementing strict operational standards to protect neighborhood character and public safety.

How to Start a Short-Term Rental Business in Thornton

Step 1: Verify Eligibility

• Primary Residence Requirement: You must reside in the property as your primary residence for more than 50% of the year
• Property Type: Single-family attached or detached dwellings, or approved accessory dwelling units when the principal dwelling is your primary residence
• Zoning Compliance: Ensure your property is in a zoning district that permits short-term rentals

Step 2: Obtain Required Licenses

• Short-Term Rental License: Required under Section 18-54 of the Thornton City Code
• Sales and Use Tax Business License: Must be obtained concurrently under Chapter 26 of the City Code
• One License Per Person/Property: Only one STR license per applicant and per property

Step 3: Complete Application Process

• Submit complete application to the city's designated department
• Include all required documentation (detailed below)
• Pay applicable fees
• Ensure compliance with all operational regulations

Step 4: Maintain Ongoing Compliance

• Renew license annually
• Remit all applicable taxes
• Comply with safety and operational requirements
• Respond to violations within specified timeframes

Required Documents, Permits, and Licenses

Short-Term Rental License Application (Section 18-54)

Required Submittal Items:

1. Application Form: Completed and signed by the property owner
2. Proof of Ownership: Verified against Adams County Assessor's website
3. Application Fee: $180 initial and annual renewal fee (+$25 late renewal fee)
4. Letter of Intent: Describe which portions of the dwelling will be used for STR
5. Previous Violation Records: If you previously held an STR license, submit any disciplinary records
6. Plan Set: Format, size, and scale to accurately depict the STR portions
7. Sales/Use Tax Business License Application: Must be submitted concurrently
8. Self-Certification Checklist:
   • Information accuracy under penalty of perjury
   • Intent to obtain required insurance
   • HOA notification (if applicable, sent 7 days prior)
   • Agreement to comply with operational requirements

Additional Requirements

• US Legal Residency: Applicant must be a legal US resident
• Property Owner: Must hold fee title (individual or trust beneficiary)
• Alternative Contact: At least one person who can respond within 60 minutes
• Insurance Verification: Proof of $1M liability coverage

Sales and Use Tax Business License

• Concurrent Application: Required under Chapter 26 of Thornton City Code
• Tax Collection: Must collect and remit lodging taxes to the city

Specific Regulations for Thornton STRs

Property Eligibility and Occupancy

• Eligible Properties: All or portion of single-family attached/detached dwellings; approved accessory dwelling units (when principal dwelling is owner's primary residence)
• Primary Residence Standard: Must be your principal domicile where you reside >50% of the year, evidenced by daily presence, utility bills, voter registration, etc.
• Maximum Occupancy:
  • Overnight: 2 persons per legal conforming bedroom + 2 additional persons
  • Total users (including day guests): Overnight occupants + 10 additional persons (max 10 total)
• No Additional Parking Required: Must comply with existing parking regulations

Safety Requirements

Mandatory Equipment:

• Smoke Detectors: One in each bedroom, each sleeping area, and outside sleeping areas
• Carbon Monoxide Detectors: One outside each sleeping area within 15 feet of bedroom doors
• Fire Extinguisher: Located near kitchen/cooking area (or in sleeping area if no cooking space)
• Construction Restrictions: Cannot rent during unsafe construction/repair periods

Insurance and Liability

• Minimum Coverage: $1,000,000 liability insurance required
• Verification: Must provide proof of insurance with renewal applications

Operational Restrictions

• Commercial Events Prohibited: No weddings, parties, or similar commercial activities
• Advertising Requirements: License number must be clearly displayed on all advertisements
• Compliance: Must comply with all applicable city, state, and federal laws
• Primary Residence Only: Cannot operate STR where you don't maintain primary residency

Guest Information Requirements

Must post inside STR:

• License number
• Property owner/emergency contact information
• Emergency services contact information
• Maximum occupancy limits
• Trash receptacle locations and collection procedures
• Noise regulations
• Authorized marijuana use areas
• General behavioral expectations

Parking and Zoning

• No Additional Parking: STRs must comply with existing parking requirements
• Off-Street Parking Expansion: Requires approval through standard development processes
• Zoning Compliance: Allowed as accessory use in residential districts (see Use Chart in Section 18-160)

Accessory Dwelling Unit (ADU) Specific Rules

• Owner Occupation: Either principal dwelling or ADU must be owner-occupied
• No Simultaneous Operation: Cannot operate both principal dwelling and ADU as STRs
• Deed Restrictions: Required deed restrictions filed with Adams County Clerk and Recorder

License Administration and Enforcement

License Term and Renewal

• Term: Valid for one year from issuance date
• Renewal Timeline: Submit renewal application at least 30 days before expiration
• Late Fees: $25 penalty for late renewals
• Non-Transferable: Licenses cannot be transferred between properties or owners
• One License Limit: One license per person across all Thornton properties

Enforcement Actions

Immediate Suspension: Up to 14 days without hearing for public health/safety threats Violation Notice: 14-day cure period for most violations Hearing Process: Request hearing within 14 days of violation notice Penalties:

• 2+ violations (cured): May impact renewal decisions
• 3 violations (cured): Discretionary denial/approval
• 4+ violations: Automatic denial
• Fraud/misrepresentation: Automatic revocation

Ineligibility Periods

• Revocation/Denial: Cannot apply for new license for 2 years
• 2 Consecutive Suspensions: Cannot apply for 5 years from second suspension

Right of Entry

• Inspection Authority: Peace officers authorized to enter with probable cause for safety violations
• Notice Requirements: Must present credentials to occupants and request entry
• Constitutional Compliance: Entry must respect occupant rights

Contact Information

Primary Authority

City of Thornton - Code Compliance Department

• Administration: City Manager or designee administers STR regulations
• Website: Short-Term Rentals Information

Department Contacts

Note: Specific phone numbers and email addresses for the STR licensing department were not provided in the source documents. Contact through the main city channels:

• City Hall: Contact main city line for department transfer
• Online Resources: Thornton 311 system for service requests
• In-Person: Thornton City Hall for application submission

Additional Contacts

• Adams County Assessor: For property ownership verification
• HOA Notification: Contact applicable homeowners' associations

State-Level Regulations (Colorado)

As Thornton operates within Adams County, the following state-level context applies:

Colorado STR Environment

• No Statewide Regulations: Colorado does not impose STR-specific regulations at the state level
• Local Authority: Counties and cities have broad authority to regulate STRs
• Adams County: Has not implemented county-level STR ordinances, leaving regulation to individual cities

Tax Obligations

• State Sales Tax: Applies to STR revenue
• Local Taxes: Thornton combined rate is 11.75% (including lodging tax)
• Business License: Required for tax collection and remittance
• Federal Income Tax: STR income subject to federal taxation

Common Colorado STR Requirements

• Business License: Required in most jurisdictions
• Sales Tax Collection: Must collect and remit state and local sales taxes
• Insurance: Liability coverage typically required
• Safety Standards: Local health and safety requirements apply

Source Links

1. Thornton STR Ordinance 2020-099: www.thorntonco.gov/media/file/short-term-rental-ordinance
2. STR Licensing Requirements: www.thorntonco.gov/media/file/short-term-rental-licensingdraftpdf
3. Thornton STR FAQ: thorntonco.qscend.com/311/knowledgebase/article/13260
4. License Requirement Information: thorntonco.qscend.com/311/knowledgebase/article/13262
5. Colorado STR Overview: www.gosummer.com/post/colorado-short-term-rental-laws
6. Thornton STR Information Page: www.thorntonco.gov/city-services/code-compliance

Disclaimer: This guide is based on the provided source materials as of the time of research. Regulations may change, and investors should verify current requirements with the City of Thornton before proceeding with any STR investment or licensing.