Arapahoe County, CO Accessory Structures: ADU Rental Restrictions (2026)

" This sits alongside the section's other ownership rules, an ADU must be under the same ownership as the principal dwelling, cannot be sold independently of it, and cannot exist on a lot unless the principal single-family dwelling is actually being used as such. Because an ADU is treated as an accessory use rather than a separate dwelling for density purposes, the code ties short-term rental eligibility specifically to lot size rather than to the ADU's own square footage or configuration. This is a distinct, narrower rule from any general short-term rental licensing framework the county maintains, it applies only to the ADU itself, not to a principal dwelling on the same lot, and it does not apply inside incorporated cities and towns such as Aurora, Centennial or Littleton, which regulate short-term rentals under their own municipal codes.