CO Code § 39-21-107 (2021)
2021 Colorado Code|Title 39 - Taxation|Article 21 - Procedure and Administration|Part 1 - General Provisions|§ 39-21-107. Limitations

  Except as provided in this section, in section 29-2-106.1 (5)(b), and unless such time is extended by waiver, the amount of any tax or of any charge on oil and gas production imposed pursuant to articles 24 to 29 of this title 39 or article 3 of title 42, and the penalty and interest applicable thereto, shall be assessed within three years after the return was filed, whether or not such return was filed on or after the date prescribed, and no assessment shall be made or credit taken and no notice of lien shall be filed, nor distraint warrant issued, nor suit for collection instituted, nor any other action to collect the same commenced after the expiration of such period; except that a written proposed adjustment of the tax liability by the department issued prior to the expiration of such period shall extend the limitation of this subsection (1) for one year after a final determination or assessment is made. No lien shall continue after the three-year period provided for in this subsection (1), except for taxes assessed before the expiration of such period, notice of lien with respect to which has been filed prior to the expiration of such period, and except for taxes on which written notice of any proposed adjustment of the tax liability has been sent to the taxpayer during such three-year period, in which case the lien shall continue for one year only after the expiration of such period or after the issuance of a final determination or assessment based on the proposed adjustment issued prior to the expiration of the three-year period. This subsection (1) shall not apply to income tax or to any tax imposed under article 23.5 of this title 39.    In the case of an income tax imposed by article 22 of this title 39, unless such time is extended by waiver and except as provided in subsection (2.5) of this section and section 39-22-601 (6)(e), the assessment of any tax, penalties, and interest shall be made within one year after the expiration of the time provided for assessing a deficiency in federal income tax or changing the reported federal taxable income of a partnership, limited liability company, or fiduciary, including any extensions of such period by agreement between the taxpayer and the federal taxing authorities; except that a written proposed adjustment of the tax liability by the department shall extend the limitation of this subsection (2) for one year after a final determination or assessment is made and except that, if the taxpayer has been audited by the department for the year in question and the issues raised in the audit have been settled by agreement for payment or payment of deficiencies arising therefrom, then any additional assessment shall be limited to deficiencies arising as a result of adjustments made by the commissioner of internal revenue in the final determination of federal taxable income. An assessment of income taxes having been made according to law shall be good and valid and collection thereof may be enforced at any time within six years from the date of said assessment. (2.5) Any limitations applicable to taxes, penalties, interest, fines, or charges within the scope of this article 21, as set forth in section 39-21-102 , are suspended:   For any period during which the taxpayer's assets are in the control or custody of a court in any proceeding before any court of the United States or any state, and for six months thereafter; or    For any period during which the department is prohibited from collecting by reason of a case under title 11 of the United States Code, and for six months thereafter.       For purposes of this section, a tax return filed before the last day prescribed by law or by regulation promulgated pursuant to law for the filing thereof shall be considered as filed on such last day.    In the case of failure to file a return or the filing of a false or fraudulent return with intent to evade tax, the tax may be assessed and collected at any time.    Where, before the expiration of the time prescribed in this section for the assessment of tax, both the executive director of the department of revenue or his delegate and the taxpayer have consented in writing to an assessment after such time, the tax may be assessed at any time prior to the expiration of the period agreed upon. The period so agreed upon may be extended by subsequent agreements in writing made before the expiration of the period previously agreed upon.    Nothing in this section shall be construed to limit any right accrued or revive any liability barred by any statute enacted on or before July 1, 1965.     History. Source: L. 65: P. 1136, § 2. C.R.S. 1963: § 138-9-6. L. 73: P. 1417, § 102. L. 77: (2) amended, p. 1770, § 1, effective May 18; (1) amended, pp. 1767, 1853, §§ 4, 6, effective January 1, 1978. L. 79: (1) amended, p. 1500, § 23, effective January 1, 1980. L. 83: (1) and (2) amended, p. 1510, § 1, effective May 26. L. 86: (1) amended, p. 1110, § 6, effective July 1. L. 89: (1) amended, p. 1594, § 7, effective July 1, 1993. L. 90: (2) amended, p. 450, § 29, effective April 18; (1) amended, p. 1722, § 7, effective May 1; (1) amended, p. 1723, § 8, effective July 1, 1993. L. 92: (1) amended, p. 2247, § 1, effective July 1. L. 2001: (1) amended, p. 778, § 10, effective June 1. L. 2002: (1) amended, p. 1361, § 16, effective July 1. L. 2009: (1) amended,(HB 09-1053), ch. 159, p. 690, § 13, effective August 5. L. 2017: (1) amended,(SB 17-112), ch. 144, p. 483, § 3, effective April 18. L. 2019: (2) amended and (2.5) added,(SB 19-035), ch. 64, p. 230, § 1, effective August 2. History. Source: L. 65: P. 1136, § 2. C.R.S. 1963: § 138-9-6. L. 73: P. 1417, § 102. L. 77: (2) amended, p. 1770, § 1, effective May 18; (1) amended, pp. 1767, 1853, §§ 4, 6, effective January 1, 1978. L. 79: (1) amended, p. 1500, § 23, effective January 1, 1980. L. 83: (1) and (2) amended, p. 1510, § 1, effective May 26. L. 86: (1) amended, p. 1110, § 6, effective July 1. L. 89: (1) amended, p. 1594, § 7, effective July 1, 1993. L. 90: (2) amended, p. 450, § 29, effective April 18; (1) amended, p. 1722, § 7, effective May 1; (1) amended, p. 1723, § 8, effective July 1, 1993. L. 92: (1) amended, p. 2247, § 1, effective July 1. L. 2001: (1) amended, p. 778, § 10, effective June 1. L. 2002: (1) amended, p. 1361, § 16, effective July 1. L. 2009: (1) amended,(HB 09-1053), ch. 159, p. 690, § 13, effective August 5. L. 2017: (1) amended,(SB 17-112), ch. 144, p. 483, § 3, effective April 18. L. 2019: (2) amended and (2.5) added,(SB 19-035), ch. 64, p. 230, § 1, effective August 2.    Editor's note:   Amendments to subsection (1) by Senate Bill 77-144 and House Bill 77-1076 were harmonized.   ANNOTATION   Law reviews. For article, “Taxation”, see 32 Dicta 418 (1955).   Section applicable where use taxes assessed, no return filed. It is the intent of the general assembly that this section, rather than § 39-26-210 , should be the controlling statute of limitations where use taxes are assessed but no return is filed. Dye Constr. Co. v. Dolan, 41 Colo. App. 293, 589 P.2d 497 (1978).   The limitation period under subsection (2) is four years. Pursuant to subsection (3), the limitation period commences on the entirety of a conservation easement credit on April 15 of the calendar year following the tax year for which the credit was first claimed. Markus v. Brohl, 2014 COA 146 , 412 P.3d 647.   Previously barred liabilities not revived. The general assembly intended to provide that liabilities which had already been barred by other statutory provisions on the date when this section became effective were not revived by subsection (6). Dye Constr. Co. v. Dolan, 41 Colo. App. 293, 589 P.2d 497 (1978).   Applied in CF&I Steel Corp. v. Charnes, 637 P.2d 324 (Colo. 1981); Kraftco Corp. v. Charnes, 636 P.2d 1300 (Colo. App. 1981).