Section 1.172-4 - Net operating loss carrybacks and net operating loss carryovers(a)General provisions - (1)Years to which loss may be carried -(i)In general. In order to compute the net operating loss deduction the taxpayer must first determine the part of any net operating losses for any preceding or succeeding taxable years which are carrybacks or carryovers to the taxable year in issue.(ii)General rule for carrybacks and carryovers. Except as provided in section 172 (b)(1)(C), (D), (E), (F), (G), (H), (I), and (J), paragraphs (a)(1)(iii), (iv), (v), and (vi) of this section, and § 1.172-10(a) , a net operating loss shall be carried back to the 3 preceding taxable years and carried over to the 15 succeeding taxable years (5 succeeding taxable years for a loss sustained in a taxable year ending before January 1, 1976).(iii)Loss of a regulated transportation corporation. Except as provided in subdivision (iv) of this subparagraph and § 1.172-10(a) , a net operating loss sustained by a taxpayer which is a regulated transportation corporation (as defined in section 172(g)(1)) in a taxable year ending before January 1, 1976, shall, subject to the provisions of section 172(g) and § 1.172-8 , be carried back to the taxable years specified in paragraph (a)(1)(ii) of this section and shall be carried over to the 7 succeeding taxable years.(iv)Loss attributable to foreign expropriation. If the provisions of section 172(b)(3)(A) and § 1.172-9 are satisfied, the portion of a net operating loss attributable to a foreign expropriation loss (as defined in section 172(h)) shall not be a net operating loss carryback to any taxable year preceding the taxable year of such loss and shall be a net operating loss carryover to each of the 10 taxable years following the taxable year of such loss.(v)Loss of a financial institution. A net operating loss sustained in a taxable year beginning after December 31, 1975, by a taxpayer to which section 585, 586, or 593 applies shall be carried back (except as provided in § 1.172-10(a) ) to the 10 preceding taxable years and shall be carried over to the 5 succeeding taxable years.(vi)Loss of a Bank for Cooperatives. A net operating loss sustained by a taxpayer which is a Bank for Cooperatives (organized and chartered pursuant to section 2 of the Farm Credit Act of 1933 (12 U.S.C. 1134 )) shall be carried back (except as provided in § 1.172-10(a) ) to the 10 preceding taxable years and shall be carried over to the 5 succeeding taxable years.(2)Periods of less than 12 months. A fractional part of a year which is a taxable year under sections 441(b) and 7701(a)(23) is a preceding or a succeeding taxable year for the purpose of determining under section 172 the first, second, etc., preceding or succeeding taxable year.(3)Amount of loss to be carried. The amount which is carried back or carried over to any taxable year is the net operating loss to the extent it was not absorbed in the computation of the taxable (or net) income for other taxable years, preceding such taxable year, to which it may be carried back or carried over. For the purpose of determining the taxable (or net) income for any such preceding taxable year, the various net operating loss carryovers and carrybacks to such taxable year are considered to be applied in reduction of the taxable (or net) income in the order of the taxable years from which such losses are carried over or carried back, beginning with the loss for the earliest taxable year.(4)Husband and wife. The net operating loss carryovers and carrybacks of a husband and wife shall be determined in accordance with this section, but subject also to the provisions of § 1.172-7 .(5)Corporate acquisitions. For the computation of the net operating loss carryovers in the case of certain acquisitions of the assets of a corporation by another corporation, see section 381 and the regulations thereunder.(6)Special limitations. For special limitations on the net operating loss carryovers in certain cases of change in both the ownership and the trade or business of a corporation and in certain cases of corporate reorganization lacking specified continuity of ownership, see section 382 and the regulations thereunder.(7)Electing small business corporations. For special rule applicable to corporations which were electing small business corporations under Subchapter S (section 1361 and following), chapter 1 of the Code, during one or more of the taxable years described in section 172 (b)(1), see paragraph (f) of § 1.172-1 .(b)Portion of net operating loss which is a carryback or a carryover to the taxable year in issue.(1) A net operating loss shall first be carried to the earliest of the several taxable years for which such loss is allowable as a carryback or a carryover, and shall then be carried to the next earliest of such several taxable years, etc. Except as provided in § 1.172-9 , the entire net operating loss shall be carried back to such earliest year.(2) The portion of the loss which shall be carried to any of such several taxable years subsequent to the earliest taxable year is the excess of such net operating loss over the sum of the taxable incomes (computed as provided in § 1.172-5 ) for all of such several taxable years preceding such subsequent taxable year.(3) If a portion of the net operating loss for a taxable year is attributable to a foreign expropriation loss (as defined in section 172(h)) and if an election under paragraph (c) of § 1.172-9 is made with respect to such portion of the net operating loss, then see § 1.172-9 for the separate treatment of such portion of the net operating loss.(c)Illustration. The principles of this section are illustrated in § 1.172-6 .T.D. 6500, 25 FR 11402, Nov. 26, 1960, as amended by T.D. 8107, 51 FR 43345, Dec. 2, 1986