(1)

(a)

(I) Whenever a resident individual or a nonresident individual with income from Colorado sources is required to file a federal income tax return under the provisions of section 6012 of the internal revenue code or whenever a resident individual or a nonresident individual has incurred any tax liability under any provision of this article, the individual shall make a return that shall contain a written declaration that it is made under the penalty of perjury in the second degree. The return shall set forth, in such detail as the executive director shall prescribe by regulations, the said individual's federal taxable income, the deductions, modifications, exemptions, and credits required or allowed under this article, and any other information necessary to carry out the purposes of this article. For the purpose of this section, the residence of the individual taxpayer shall be the address supplied by the taxpayer to the department of revenue on the return.

(II) For purposes of this paragraph (a), a nonresident individual whose only source of income from this state is compensation that is subtracted from federal taxable income under section 39-22-104 (4)(t) need not file a return.

(III) For purposes of this paragraph (a), an individual whose only source of income is compensation that is subtracted from federal taxable income under section 39-22-104 (4)(u) need not file a return.

(b) If any individual is unable to make his own return, the return shall be made by a duly authorized agent, guardian, executor, administrator, or other person charged with the care of the person or property of such taxpayer.

(c) Repealed.

(2) Every C corporation subject to taxation under this article shall make a return which shall contain a written declaration that it is made under the penalties of perjury in the second degree. Such return shall set forth, in such detail as the executive director shall prescribe by regulations, federal taxable income and the modifications and credits required or allowed under this article and any other information necessary to carry out the purposes of this article. The return shall be signed by the president, vice-president, treasurer, assistant treasurer, chief accounting officer, or other officer duly authorized to act. In cases where receivers, trustees in bankruptcy, or assignees are operating the property or business of corporations, such receivers, trustees, or assignees shall make returns for such corporations in the same manner and form as corporations are required to make returns. Any tax due on the basis of such returns shall be collected in the same manner as if collected from the corporation for which the return is made.

(2.5)

(a) Every S corporation which engages in activities in this state which would subject a C corporation to the requirement to make a return under this section shall make a return which shall contain a written declaration that it is made under the penalties of perjury in the second degree. Such return shall set forth, in such detail as the executive director shall prescribe by regulations, federal taxable income and the modifications and credits required or allowed under this article and any other information necessary to carry out the purposes of this article. The return shall be signed by an officer of the S corporation duly authorized to act, which authorization shall be conclusively presumed by the signature.

(b) In addition to other information which the executive director may by regulation prescribe, the return shall set forth:

(I) The name, address, and social security or federal identification number of each shareholder of the S corporation;

(II) The income attributable to the state and the income not attributable to the state with respect to each shareholder of the S corporation as determined under subpart 2 of part 3 of this article; and

(III) The modifications required by section 39-22-323.

(c) The S corporation shall, on or before the day on which such return is filed, furnish to each person who was a shareholder of the S corporation during the year a copy of such information shown on the return as the executive director may by regulation prescribe.

(d) The department of revenue shall permit S corporations to file composite returns and to make composite payments of tax on behalf of some or all of its nonresident shareholders. The department of revenue may permit composite returns and payments to be made on behalf of resident shareholders.

(e) With respect to each of its nonresident shareholders, an S corporation shall, for each taxable period, either timely file with the department of revenue an agreement, as provided in paragraph (f) of this subsection (2.5), or make a payment to this state as provided in paragraph (h) of this subsection (2.5).

(f) The agreement referred to in paragraph (e) of this subsection (2.5) is an agreement of a nonresident shareholder of the S corporation:

(I) To file a return in accordance with the provisions of paragraph (a) of this subsection (2.5) and to make timely payment of all taxes imposed on the shareholder by this state with respect to the income of the S corporation; and

(II) To be subject to personal jurisdiction in this state for purposes of the collection of income taxes, together with related interest and penalties, imposed on the shareholder by this state with respect to the income of the S corporation.

(g) An S corporation that timely files an agreement as provided in paragraph (e) of this subsection (2.5) with respect to a nonresident shareholder of the S corporation for a taxable period shall be considered to have timely filed such an agreement for each subsequent taxable period. An S corporation that does not timely file such an agreement for a taxable period shall not be precluded from timely filing such an agreement for subsequent taxable periods. The agreement will be considered to be timely filed for a taxable period and for all subsequent taxable periods if it is filed at or before the time the annual return for such taxable period is required to be filed pursuant to paragraph (a) of this subsection (2.5).

(h) The payment referred to in subsection (2.5)(e) of this section shall be in an amount equal to the highest marginal tax rate in effect under section 39-22-104 multiplied by the shareholder's pro rata share of the income attributable to the state as reflected on the S corporation's return for the taxable period. An S corporation shall be entitled to recover a payment made pursuant to this subsection (2.5)(h) from the shareholder on whose behalf the payment was made. Any such payment for a taxable period must be made at or before the time the annual return for such taxable period is required to be filed pursuant to subsection (2.5)(a) of this section.

(i) Any amount paid by the S corporation to this state pursuant to paragraph (d) or paragraph (h) of this subsection (2.5) shall be considered to be a payment by the shareholder on account of the income tax imposed on the shareholder for the taxable period pursuant to section 39-22-104.

(3) Every fiduciary, except a receiver appointed by authority of law in possession of part only of the property of an individual, shall make a return for any individuals, estates, or trusts for which he acts, which return shall contain a declaration that it is made under the penalties of perjury in the second degree. Such return shall set forth, in such detail as the executive director shall prescribe by regulation, the federal taxable income and the deductions, modifications, exemptions, and credits required or allowed under this article and any other information necessary to carry out the purposes of this article. The individuals, estates, or trusts for which afiduciary acts are as follows:

(a) Every individual for whom a return is required to be filed under subsection (1) of this section;

(b) Every resident estate or trust and every nonresident estate or trust with income from Colorado sources for which a federal income tax return is required to be filed and every resident estate or trust and every nonresident estate or trust which has incurred any tax liability under any provision of this article.

(c) Repealed.

(4) Every fiduciary of an estate or trust with a nonresident beneficiary which receives net income from real or tangible personal property within Colorado shall withhold and pay over to the executive director, out of the income to be distributed to such nonresident beneficiary, a tax upon the beneficiary's share of said income computed at the rate provided in section 39-22-104 unless the nonresident beneficiary files a timely return of his total income from sources within Colorado, in which case the fiduciary shall withhold and pay over only the amount of tax disclosed by the beneficiary's return. The nonresident beneficiary, at his option within the time limited by this article, may file a return of his income and may claim a refund for the amount of tax withheld in excess of the amount of tax due as shown by said return.(4.5) Repealed.

(5)

(a) Every partnership that engages in activities in this state that would subject a C corporation to the requirement to make a return under this section shall make a return that shall contain a written declaration that it is made under the penalties of perjury in the second degree. Such return shall set forth, in such detail as the executive director shall prescribe, federal ordinary income and the modifications and credits required or allowed under this article and any other information necessary to carry out the purposes of this article. The return shall be signed by any one of the partners.

(b) In addition to other information that the executive director may prescribe, the return shall set forth:

(I) The name, address, and social security or federal identification number of each partner of the partnership;

(II) The income attributable to the state and the income not attributable to the state with respect to each partner of the partnership as determined under section 39-22-203; and

(III) The modifications required by section 39-22-202.

(c) The partnership shall, on or before the day on which the return is filed, furnish to each person who was a partner of the partnership during the year a copy of such information shown on the return as the executive director may prescribe.

(d) The department of revenue shall permit partnerships to file composite returns and to make composite payments of tax on behalf of any or all of its nonresident partners.

(e) With respect to each of its nonresident partners, a partnership shall, for each taxable period, either timely file with the department of revenue an agreement, as provided in paragraph (f) of this subsection (5), or make payment to this state, as provided in paragraph (h) of this subsection (5).

(e.5) Paragraphs (d) and (e) of this subsection (5) shall not apply to a publicly traded partnership, as defined in section 7704 (b) of the internal revenue code, that meets any of the exceptions under section 7704 (c) of the internal revenue code and is not treated as a corporation under section 7704 (a) of the internal revenue code.

(f) The agreement referred to in paragraph (e) of this subsection (5) is an agreement of a nonresident partner of the partnership:

(I) To file a return in accordance with the provisions of paragraph (a) of this subsection (5) and to make timely payment of all taxes imposed on the member by this state with respect to the income of the partnership; and

(II) To be subject to personal jurisdiction in this state for purposes of the collection of income taxes, together with related interest and penalties, imposed on the partner by this state with respect to the income of the partnership.

(g) A partnership that timely files an agreement as provided in paragraph (e) of this subsection (5) with respect to a nonresident partner of the partnership for a taxable period shall be considered to have timely filed such an agreement for each subsequent taxable period. A partnership that does not timely file such an agreement for a taxable period shall not be precluded from timely filing such an agreement for subsequent taxable periods. The agreement will be considered to be timely filed for a taxable period and for all subsequent taxable periods if it is filed at or before the time the annual return for such taxable period is required to be filed pursuant to paragraph (a) of this subsection (5).

(h) The payment referred to in subsection (5)(e) of this section shall be in an amount equal to the highest marginal tax rate in effect under section 39-22-104 multiplied by the nonresident partner's share of the income attributable to the state as reflected on the partnership's return for the taxable period. A partnership shall be entitled to recover a payment pursuant to this subsection (5)(h) from the nonresident partner on whose behalf the payment was made. Any such payment for a taxable period must be made at or before the time the annual return for such taxable period is required to be filed pursuant to subsection (5)(a) of this section.

(i) Any amount paid by the partnership to this state pursuant to paragraph (d) or (h) of this subsection (5) shall be considered to be a payment by the nonresident partner on account of the income tax imposed on the nonresident partner for the taxable period pursuant to section 39-22-104 or 39-22-301.

(6)

(a) Any final determination of federal taxable income made pursuant to the provisions of federal law under which federal taxable income is found to differ from the taxable income originally reported to the federal government shall be reported by the taxpayer to the executive director by making and filing a Colorado amended return within thirty days of such final determination with a statement of the reasons for the difference, in such detail as the executive director may require. In addition thereto, any taxpayer filing an amended return with the federal internal revenue service that reflects any change in income reportable to the state of Colorado shall, within thirty days of such federal filing, make and file a corresponding Colorado amended return.

(b) For purposes of this subsection (6), final determination means only the first of the following to occur:

(I) The taxpayer's execution of a waiver with and acceptance by the internal revenue service of restrictions on assessment and collection of deficiency in federal tax or acceptance of overassessment in said tax;

(II) The acceptance by the internal revenue service of an offer of waiver of restrictions on assessment and collection of deficiency in tax or acceptance of overassessment;

(III) The execution by the taxpayer of acceptance of an examining officer's findings by a partnership, limited liability company, or fiduciary;

(IV) The payment of any additional tax by the taxpayer; or

(V) Any judgment becoming final, whether by stipulation or otherwise, in any judicial roceeding affecting such change in reported federal taxable income.

(c) If, from such return or from investigation, it appears that the tax with respect to income imposed by this article has not been fully assessed, the executive director shall, within one year after the receipt of such return or within one year of discovery of such final determination, if unreported, assess the deficiency with interest at the rate prescribed in section 39-22-621.

(d) If the taxpayer does not file such amended return within the prescribed thirty-day period, then the statute of limitations shall be tolled from the end of such thirty-day period until the date that such amended return is filed with the executive director or until the executive director discovers such determination or change, whichever shall first occur.

(e) If any taxpayer agrees with the internal revenue service for an extension, or renewals thereof, of the period for assessing deficiencies or paying refunds in federal income tax or for changing reported federal taxable income of a partnership, limited liability company, or fiduciary for any year or if any taxpayer files a federal income tax refund claim or initiates administrative or judicial proceedings which have the effect of extending said period for any year, the period within which the executive director may issue a notice of deficiency for any such year shall be four years after the applicable Colorado return was filed or one year after the date of expiration of the extended period for assessing deficiencies in federal income tax or changing reported federal taxable income of a partnership, limited liability company, or fiduciary, whichever is later.

(f) Repealed.

(g) Notwithstanding any provision of this article or of article 21 of this title, any assessment made by reason of the applicability of the provisions of paragraphs (a) to (f) of this subsection (6), which could not have been made except for the extension or tolling, pursuant to said provisions, of the period of limitations otherwise applicable for assessing income taxes, shall be limited to deficiencies arising as a result of adjustments made by the commissioner of internal revenue in any final determination of federal taxable income, if the taxpayer has been audited by the department of revenue 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.

(7) Every person or organization exempt from taxes pursuant to section 39-22-112 shall make and file a return only if said person or organization is required to file a federal return of unrelated business income, which Colorado return shall contain such information as the executive director may prescribe. All procedures of law relating to the determination, assessment, collection, and refund of tax shall apply to such return and the tax payable thereon.

(8) Repealed.

(9)

(a) Any person who is required by section 6053 or 6041A of the internal revenue code to file annual information reports concerning tips or remunerations for services or remunerations for direct sales may be required, by rules promulgated by the executive director, to file copies of such reports or otherwise furnish the same to the executive director within the time required by the internal revenue service for the filing of such reports. Such reports shall show, in addition to the information required by the internal revenue service, any amounts deducted and withheld by the payor for income tax due to the state of Colorado from the payee listed on such reports.

(a.5) The executive director may require any magnetic media taxpayer to file the reports described in paragraph (a) of this subsection (9) by magnetic media or in other machine-readable form. For the purposes of this paragraph (a.5), "magnetic media taxpayer" means a taxpayer who is required to file information returns described in section 6041A, 6051, or 6053 of the internal revenue code by magnetic media or in other machine-readable form under section 6011 (e) of the internal revenue code.

(b) Any person required by paragraph (a) of this subsection (9) to file a report who fails to timely file such report shall be subject to a fine of fifty dollars for each such failure.

(10) Repealed.