Boulder Comprehensive
Rental Guide

Boulder is one of Colorado's most desirable — and regulated — rental markets. With the University of Colorado drawing tens of thousands of students, a thriving tech sector, and world-class outdoor recreation, demand for rental housing remains consistently high. At the same time, the city has long maintained a comprehensive licensing and inspection framework that requires landlords to stay actively informed.

Recent years have brought significant change: Colorado's HB24-1007 ended family-based occupancy limits, HB24-1152 revolutionized ADU development rights, the March 2025 city council vote formally abolished unrelated-person caps, parking minimums were eliminated in August 2025, and the Sundance Film Festival's 2027 relocation to Boulder has created an entirely new short-term rental category.

This guide covers every licensing category, the current regulatory landscape, bedroom and space standards, parking requirements, IRS tax strategies, and step-by-step compliance checklists — all in one place.

Rates by Neighborhood

Sources: Rentometer, Zumper, Apartments.com (2025–2026 data). Rates are averages; actual rents vary by unit condition, amenities, and lease terms.

Boulder's Land Use Code divides the city into zoning districts that determine what types of rental uses are permitted. As of 2024–2025 code revisions, many former use restrictions have been eased, and ADUs are now permitted by right in all single-family zones.

Standard long-term rentals are defined as rentals of 30 days or more at a time. All long-term rental properties in Boulder must have a valid rental license under the Boulder Revised Code (B.R.C. 1981) and the city's Property Maintenance Code.

Step-by-Step: Getting a Long-Term License

Exemptions to the License Requirement

A rental license is not required when:

• The owner lives on the property and rents to a relative
• The owner is temporarily living outside Boulder County (temporary exemption available)
• The property qualifies under other specific exemptions per Boulder Revised Code

Note: These exemptions do NOT apply to short-term rentals. Submit a Rental License Exemption Affidavit – Owner/Relative Occupied form if claiming an exemption.

Out-of-County Owner Requirements

Required Landlord Disclosures

Permanently Affordable Housing Units

Properties in Boulder's Regional Affordable Homeownership Program (BVCP) have strict rental restrictions: short-term rentals are never permitted, whole-home rentals are limited to one year out of every seven, and owner occupancy (defined as residing in the home 10 months per calendar year) is required. Contact homeownership@bouldercolorado.gov for case-specific guidance.

Short-term rentals (STRs) are properties rented for 29 days or fewer at a time. In Boulder, STRs are strictly regulated: the property must be the owner's principal residence, and non-owner-occupied properties are not eligible for a standard short-term rental license.

Key Requirements

Fees & License Terms

Taxes on Short-Term Rentals

All STR income is subject to Boulder's accommodations tax. File quarterly returns through the Boulder Online Tax System (salestax@bouldercolorado.gov). Annual sales and use tax filing is also required.

Timeline of This License

Who Is Eligible?

Key Rules for the Festival Lodging License

For Landlords: Tenant Subleasing During Sundance

Pricing Guidance

Some Boulder homes are listed on Airbnb for well over $100,000 for the 11-day festival. However, most Sundance attendees are drive-in visitors from around Colorado who are price-sensitive. The city advises competitive pricing to maximize bookings and keep visitors staying in Boulder rather than outlying communities. Visit Boulder has vetted property management partners to help owners handle listing and guest services.

What Is an ADU?

An Accessory Dwelling Unit is a self-contained secondary living space on the same lot as a primary single-family home. It must have its own entrance, kitchen, and living space. ADUs can be:

HB24-1152: Colorado's ADU Law (Effective June 30, 2025)

Boulder's ADU Standards (As of 2025)

ADU Rental Income Potential

Important ADU Restrictions That Remain

• ✗ADUs cannot be sold separately from the primary home — must remain on the same lot
• ✗Short-term rentals from an ADU are prohibited unless both the STR license and ADU were legally established before January 3, 2019
• ✗Permanently affordable homes are not eligible for ADUs
• ✓Both the primary home and the ADU may be separately rented long-term under the new rules (no owner-occupancy required)

ADU Construction Costs (Boulder Estimates)

Garage conversion: $80,000–$180,000 | New detached build: $160,000–$320,000 | Prefab/modular: $120,000–$270,000. Impact fees and utility connection costs still apply and vary significantly by location — in some communities these fees alone can exceed $60,000 for water/sewer connections.

HB24-1007: Colorado HOME Act (Effective July 1, 2024)

Boulder's March 2025 City Council Action

Prior history: Boulder previously limited occupancy to 3 unrelated persons (pre-2023), then raised that to 5 unrelated persons in August 2023, before fully repealing relationship-based limits in March 2025 under the state mandate.

What Occupancy Rules Now Apply

Occupancy in Boulder rental properties is now governed entirely by the International Property Maintenance Code (IPMC), which sets minimum health-and-safety-based space standards. There is no longer a cap on the number of unrelated persons — only the physical space limits apply.

For Landlords: Writing Compliant Lease Language

Now that family-based occupancy limits are removed, the IPMC's physical space standards are the primary mechanism for determining how many people can legally occupy a rental unit. These rules apply to all rental properties — whether for a single renter or a house full of roommates.

Full IPMC Space Requirements Summary

Bathroom Requirements for Large Households

The IPMC does not specify a maximum occupants-per-bathroom ratio for rental housing per se, but the bathroom access rule is critical: every bedroom must connect to a water closet and lavatory without passing through another bedroom. As households grow larger, ensure your floor plan does not create situations where one bedroom is a required passageway to a bathroom serving another bedroom.

What Changed

What Did Not Change

Neighborhood Parking Permit (NPP) Program Changes — Jan. 1, 2026

Practical Guidance for Landlords

While off-street parking is no longer required, providing it remains a meaningful amenity that influences rents and tenant demand. Properties in neighborhoods with NPP zones should disclose parking limitations to prospective tenants. Large-household rentals (post-HB24-1007) may generate more vehicles than the neighborhood expects — be prepared for community conversations.

March 2025 represented one of the most active months of regulatory change for Boulder landlords in recent memory. Three major actions occurred:

SmartRegs is Boulder's mandatory energy efficiency standard for rental properties, adopted in 2010. All long-term rental properties must comply with SmartRegs before a rental license application can be approved.

HERS Rating Alternative

Properties with a HERS (Home Energy Rating System) Rating of 120 or less do not need a SmartRegs inspection — submit the rating with your application for automatic compliance.

What SmartRegs Inspects

Insulation levels, appliances, HVAC systems, windows, shared walls/ceilings/floors, lighting, and air leakage (blower door test). Inspectors are private contractors certified by the city. You choose your inspector and negotiate the fee directly — the city is not a party to that contract.

SmartRegs and ADUs

• Properties with a detached accessory unit are required to pass SmartRegs
• Properties with an attached accessory unit are not required to pass SmartRegs for the accessory unit
• Each unit on a duplex requires its own SmartRegs inspection

Cost Range

Some condos and newer homes pass with no upgrades. Older single-family homes (1960s era) with poor insulation, old furnaces, and original windows may require up to $10,000 or more in improvements to achieve compliance.

What Is the Augusta Rule?

IRS Code Section 280A(g), informally known as the "Augusta Rule" or "Masters Rule," allows homeowners to rent their personal residence for 14 days or fewer per year and exclude that rental income entirely from their federal gross income — it is not reported on Form 1040, Schedule E, or anywhere on the personal tax return.

The provision is named for homeowners in Augusta, Georgia, who lobbied Congress in the 1970s to avoid tax consequences when renting their homes during the Masters golf tournament. Congress codified the exception in Section 280A, and it now applies nationwide.

Key Rules and Requirements

The Business Owner Strategy

Boulder-Specific Applications

The Augusta Rule is particularly relevant for Boulder homeowners in proximity to high-demand events where short-term rental premiums are possible:

• Sundance Film Festival (Jan. 2027): The 11-day event falls within the 14-day threshold. An owner who uses only the Augusta Rule (not a Festival Lodging License) could rent their home for up to 14 days without reporting the income — but would also not be eligible for rental expenses.
• CU events, concerts, sports: High-demand periods may allow premium pricing under the 14-day exemption.
• Business retreats: Boulder's appeal as a retreat destination makes fair-market rates easy to document.

Annual Landlord Compliance Checklist

Tenant Screening in the Post-HB24-1007 World

Colorado Security Deposit Changes — Jan. 1, 2026