Colorado Revised Statutes Title 39. Taxation § 39-5-125. Omission--correction of errors

(1) Except as otherwise provided in subsection (3) of this section, whenever it is discovered that any taxable property has been omitted from the assessment roll of any year or series of years, the assessor shall immediately determine the value of such omitted property and shall list the same on the assessment roll of the year in which the discovery was made and shall notify the treasurer of any unpaid taxes on such property for prior years.

(2) Omissions and errors in the assessment roll, when it can be ascertained therefrom what was intended, may be supplied or corrected by the assessor at any time before the tax warrant is delivered to the treasurer or by the treasurer at any time after the tax warrant has come into his hands.

(3) If taxable personal property that has been omitted from the assessment roll of any year or series of years is discovered due to a property owner or an agent of a property owner who advertises for rent furnished residential real property providing information to the assessor pursuant to section 39-5-108.5(2), the assessor shall not notify the treasurer of any unpaid taxes on the taxable personal property for prior years and the property owner or agent shall not be liable for any such unpaid taxes for prior years.

(4) If omitted property is added by the assessor or the treasurer for a prior assessment year, then a petition for abatement or refund may be filed at any time after the taxes are levied and an amended tax bill has been generated, but before two years after January 1 of the year following the year in which the taxes are levied.