Did Boulder really drop its ADU saturation caps and owner-occupancy rule?
✓ Verified against code · August 19, 2026
Yes, in stages: the per-block saturation caps ended September 1, 2023, and owner-occupancy ended March 8, 2025 under the state ADU law. If a guide mentions caps, waitlists, or living on site, it's describing the old regime.
Citation: Ord 8571 (2023); Ord 8650 (2025); city ADU page
How current is this?
Boulder’s ADU rules run under B.R.C. 9-6-3(n) (Boulder Revised Code) (Ordinance 8650 (building on Ord 8571)). Boulder spent two decades as one of the country's most ADU-restrictive cities and unwound it in stages: the per-block saturation caps died in September 2023 (Ord 8571), and owner-occupancy ended March 8, 2025 (Ord 8650). Older Boulder ADU lore — caps, waitlists, owner-occupancy — describes a code that no longer exists, but the size limits remain among the region's tightest. We verified this answer against primary sources on August 19, 2026, and every change we catch is logged in the changelog.
More Boulder ADU questions
- How big can a Boulder detached ADU be?
- Can I Airbnb a Boulder ADU?
- Do I need parking for a Boulder ADU?
All Boulder ADU rules → · Compare Colorado cities →
Not legal advice — lot-specific overlays can change the answer for your parcel. The citation above points at the governing code section; check it, or ask the city to confirm.