Colo. Rev. Stat. § 1-1-202
The regular terms of office of all nonpartisan officers elected at regular elections shall commence at the next meeting of the governing body following the date of the election, but no later than thirty days following the survey of returns and upon the signing of an oath and posting of a bond, where required, unless otherwise provided by law. If the election is canceled in whole or in part pursuant to section 1-5-208 (1.5), then the regular term of office of a nonpartisan officer shall commence at the next meeting of the governing body following the date of the regular election, but no later than thirty days following the date of the regular election and upon the signing of an oath and posting of a bond, where required, unless otherwise provided by law.
C.R.S. § 1-1-202