Colorado

Colorado enacted statewide ADU legislation in 2024, requiring municipalities to permit accessory dwelling units on residential lots. Denver, Boulder, and Colorado Springs had already adopted ADU-friendly zoning, and the new law extends that right across the state. ADU Pass helps Colorado property owners handle the permit process from start to finish.

642 ZIP codes
64 Counties
371 Cities

State ADU details

State ADU law

Colorado enacted statewide ADU preemption through HB24-1152, signed by Governor Jared Polis in May 2024 with effective date 2025-06-30. The act applies to 'subject jurisdictions': municipalities with population at least 1,000 that lie within a Metropolitan Planning Organization (MPO), and counties containing a census-designated place of at least 40,000 within an MPO. Subject jurisdictions must permit at least one ADU as a use-by-right accessory to any single-unit detached dwelling, with administrative approval (no public hearing) and prohibitions on parking minimums and owner-occupancy mandates. Local governments may continue to set design standards, impact fees (subject to limits), short-term-rental rules, and factory-built-residential standards. The act creates a tiered preemption: local rules that conflict with the floor are void in subject jurisdictions; non-subject (rural) jurisdictions may opt in to gain access to the state's $8M ADU finance program through DOLA's ADU Supportive Jurisdiction certification. The Colorado Common Interest Ownership Act (CCIOA) was simultaneously amended at C.R.S. § 38-33.3-106.5 to void HOA bans on ADUs (see stateHoaPreemption).

State HOA preemption

Colorado HB24-1152 amended the Colorado Common Interest Ownership Act (CCIOA) to void HOA bans on ADUs. The new C.R.S. § 38-33.3-106.5 prohibits any provision of a Declaration, Bylaw, or Rule from restricting the creation of an ADU as an accessory use to any single-unit detached dwelling. Restrictions adopted before or after the effective date are void as a matter of public policy. The provision applies to all common-interest communities (CCIOA, pre-CCIOA, and limited-expense communities) and is not subject to the small-HOA exemptions in SB24-021. Associations may impose 'Reasonable Restrictions' defined as substantive conditions that do not unreasonably increase cost, effectively prohibit construction, or extinguish the ability to construct an ADU.

State financing programs

Colorado operates one of the most explicit state ADU finance regimes in the country, created by HB24-1152. The Colorado Office of Economic Development and International Trade (OEDIT) funded an $8 million revolving program; the Colorado Housing and Finance Authority (CHFA) administers loans, interest-rate buydowns, and credit enhancement for participating lenders. The application period opened to lenders in December 2025; ADU finance products become available to eligible Colorado residents in ADU Supportive Jurisdictions in spring 2026, with interest-rate buydowns and credit enhancement reaching borrowers later in 2026. Eligibility is restricted to ADU Supportive Jurisdictions (subject jurisdictions automatically qualify; non-subject jurisdictions must apply to DOLA for certification).

State insurance regimes

Colorado launched a state FAIR Plan in April 2025 in response to wildfire-driven non-renewal pressure following the 2021 Marshall Fire (over 1,000 homes destroyed; 74% of affected homeowners underinsured). HB23-1288 (signed 2023-05-12) authorized the Colorado FAIR Plan Association as the insurer of last resort; residential applications opened 2025-04-10. Coverage is capped at $750,000 for residential and $5M for commercial; policies are written on actual cash value (ACV) rather than replacement cost; eligibility requires three declines from licensed standard insurers and confirmation by a licensed agent. Colorado is the sixth-costliest state for homeowners insurance with ~$4,072 average annual premium for $300K dwelling coverage; premiums rose 58% from 2018 to 2023. Wildland-urban interface (WUI) exposure drives most underwriting decisions; defensible space, Class A roofing, and Wildfire Prepared Home certifications meaningfully affect rates.

State housing programs

Colorado operates the most fully-developed state ADU support framework in the country outside California. The Colorado Department of Local Affairs (DOLA) Division of Local Government (DLG) maintains an ADU Toolkit and a guide to providing pre-approved ADU plans, certifies ADU Supportive Jurisdictions, and administers the ADUG grant program for jurisdictions implementing those tools. The framework explicitly funds three local activities: developing pre-approved ADU plans, providing technical assistance to homeowners, and waiving or reducing ADU fees. ~$1.6M flowed through ADUG round 1 (FY2025-2026); round 2 deadline 2026-03-18. The Accessible/Visitable ADU incentive program adds a separate funding track for ADUs designed to ADA-style standards.

Known state issues (2)

  • policy-review (since 2025-06) — Practitioners should verify each Colorado subject jurisdiction's current ADU ordinance status and ADU Supportive Jurisdiction certification status. CHFA ADU finance products are not yet broadly available to borrowers as of this check. (source)
  • policy-review (since 2025-04) — ADU owners in WUI zones should plan for FAIR Plan as last resort if admitted-market coverage is unavailable; expect ACV-only settlement which materially affects rebuild economics. (source)
Federal (United States) — ADU-relevant rules and programs

Federal ADU law

The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.

Federal financing programs

Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.

Federal tax credits

There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.

Federal housing programs

HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.

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