Colorado § 31-12-113 - Effective date of annexation - required filings.
Full text of Colorado Colorado Revised Statutes § 31-12-113 — Effective date of annexation - required filings., with citation guidance and answers to common questions.
§ 31-12-113. Effective date of annexation - required filings.
(1) If the conditions of subsection (2) of this section are met, area annexed to a municipality, as provided in this part 1, shall be annexed upon the effective date of the annexing ordinance, except as otherwise provided in sections 31-12-118 and 31-12-118.5 and for tax purposes as provided in subsection (3) of this section.
(2) (a) The annexing municipality shall:
(I) File one copy of the annexation map with the original of the annexation ordinance in the office of the clerk of the annexing municipality;
(II) (A) File for recording three certified copies of the annexation ordinance and map of the area annexed containing a legal description of such area with the county clerk and recorder of each county affected.
(B) The county clerk and recorder of each county involved shall file one certified copy of such annexation ordinance and map with the division of local government of the department of local affairs and one certified copy of such annexation ordinance and map with the department of revenue.
(a.5) Upon receiving an annexation ordinance and map pursuant to sub-subparagraph (B) of subparagraph (II) of paragraph (a) of this subsection (2), the department of revenue shall communicate with any taxing entities affected by the annexation in order to facilitate the administration and collection of taxes within the annexed areas and to identify all retailers affected by the annexation. The department of revenue shall make copies of any such ordinances and maps available to all taxing entities in the state, including any special districts that impose a sales tax.
(b) No annexation shall be effective until the requirements of sub-subparagraph (A) of subparagraph (II) of paragraph (a) of this subsection (2) are met.
(c) In any action attacking the validity of an annexation proceeding, failure of the annexing municipality to have made the filings required by this subsection (2) shall not be deemed to invalidate the annexation where good cause for such failure is shown.
(3) An annexation shall be effective for the purpose of general taxation on and after the January 1 next ensuing.
(4) In the event that an annexation which has the effect of changing county lines occurs before January 1, the assessor of the county from which such area was detached shall provide to the assessor of the county to which such area has been added, on or before the February 1 next ensuing, the following:
(a) An abstract of the total valuation for assessment of all taxable property so transferred;
(b) A certified copy of the assessment records of the individual properties in the annexed area as of the effective date of annexation containing the legal description, the name and address of the owner, and the valuation for assessment of all taxable property, together with such supporting records as are required by the regulations of the property tax administrator.
Source: L. 75: Entire title R&RE, p. 1086, § 1, effective July 1. L. 99: (1) amended, p. 1, § 1, effective February 1. L. 2000: (2)(a)(II) amended and (2)(a.5) added, p. 422, § 2, effective August 2.
Editor's note: This section is similar to former § 31-8-113 as it existed prior to 1975.
ANNOTATION
Annotator's note. Since § 31-12-113 is similar to former § 31-8-113 prior to the 1975 repeal and reenactment of this title, relevant cases construing that provision have been included in the annotations to this section.
Read with § 31-21-120. The legislative intent is clear, and § 31-12-116 and this section must be read in conjunction with § 31-12-120. Bd. of County Comm'rs v. City & County of Denver, 190 Colo. 347, 547 P.2d 249 (1976).
Annexation ordinance becomes effective after completion of annexation proceedings. Green Valley Ranch Venture Co. v. District Court, 186 Colo. 173, 526 P.2d 141 (1974).
District court does not have jurisdiction to review county petition for judicial review of an annexation when the petition is not timely filed within 10 days of the effective date of annexation. County of Teller v. City of Woodland Park, 2014 CO 35, 333 P.3d 55.
This section does not control "the effective date of the ordinance" referred to in § 31-12-116 (2)(a)(II). The effective date of the ordinance and the effective date of the annexation are distinct from one another. County of Teller v. City of Woodland Park, 2014 CO 35, 333 P.3d 55.
Filing requirements of subsection (2)(a)(II)(A) and § 24-32-109 not satisfied by mere substantial compliance. There are several clear indications in these statutory provisions that substantial compliance with filing requirements is insufficient. Both statutes plainly declare that the consequence of noncompliance is that annexation shall not become effective. Unlike statutes governing annexations by petition, this section and § 24-32-109 do not expressly allow for substantial compliance. Presence of an explicit good cause exception in subsection (2)(c) suggests general assembly intended that only a showing of good cause would excuse strict compliance. Grandote Golf & Ctry. Club v. Town of La Veta, 252 P.3d 1196 (Colo. App. 2011).
Even assuming that substantial compliance with this section and the requirements of § 24-32-109 may render an annexation effective, there was no substantial compliance with additional requirement that a certified copy of the annexation ordinance and map be filed with division of local government. This requirement cannot be deemed a mere formality; excusing noncompliance with this requirement would not result in fulfillment of the relevant statutes' purposes. Grandote Golf & Ctry. Club v. Town of La Veta, 252 P.3d 1196 (Colo. App. 2011).
Because required filings of annexation ordinance did not occur, and because no good cause was shown (or even alleged for the failure), the annexation contemplated by the ordinance did not become effective. Grandote Golf & Ctry. Club v. Town of La Veta, 252 P.3d 1196 (Colo. App. 2011).
Source: official Colorado text · Last verified 2026-08-27
Frequently Asked Questions About Colorado § 31-12-113
What does Colorado Revised Statutes § 31-12-113 cover?
Section 31-12-113 ("Effective date of annexation - required filings.") is part of the Colorado Revised Statutes, the codified statutory law of Colorado. It sets out the legal rule or procedure described in the text above. Statutes are amended regularly, so always verify against the official source.
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