Internal Revenue Code · 26 U.S.C.
§ 39. Carryback and carryforward of unused credits
Official text, no changes From the Office of the Law Revision Counsel, release point 119-121 (current through Public Law 119-121 (October 9, 2026)). Compare it with the official text at uscode.house.gov (external site).
Cite as 26 U.S.C. § 39
At a glance
Read from the text, the source credit and the official notes. Not part of the law.
- Status
- In force
- Added
- July 18, 1984 by Pub. L. 98–369
- Last amended
- August 16, 2022 by Pub. L. 117–169
- Amendments
- 15 dated changes in the source credit
- Length
- 4 subsections · 906 words · about 4 min to read
- Cross-references
- cites 2; cited by 15 Code sections and 28 other regulations
The entire amount of the unused credit for an unused credit year shall be carried to the earliest of the 21 taxable years to which (by reason of paragraph (1)) such credit may be carried.
The amount of the unused credit for the unused credit year shall be carried to each of the other 20 taxable years to the extent that such unused credit may not be taken into account under section 38(a) for a prior taxable year because of the limitations of subsections (b) and (c).
The amount of the unused credit which may be taken into account under section 38(a)(1) for any succeeding taxable year shall not exceed the amount by which the limitation imposed by section 38(c) for such taxable year exceeds the sum of the amounts which, by reason of this section, are carried to such taxable year and are attributable to taxable years preceding the unused credit year.
No portion of the unused business credit for any taxable year which is attributable to a credit specified in section 38(b) or any portion thereof may be carried back to any taxable year before the first taxable year for which such specified credit or such portion is allowable (without regard to subsection (a)).
(Added Pub. L. 98–369, div. A, title IV, § 473, July 18, 1984, 98 Stat. 828; amended Pub. L. 99–514, title II, § 231(d)(3)(C)(i), title XVIII, § 1846, Oct. 22, 1986, 100 Stat. 2179, 2856; Pub. L. 100–647, title I, § 1002(l)(26), Nov. 10, 1988, 102 Stat. 3381; Pub. L. 101–508, title XI, §§ 11511(b)(2), 11611(b)(2), 11801(a)(2), Nov. 5, 1990, 104 Stat. 1388–485, 1388–503, 1388–520; Pub. L. 102–486, title XIX, § 1914(c), Oct. 24, 1992, 106 Stat. 3023; Pub. L. 103–66, title XIII, §§ 13302(a)(2), 13322(d), 13443(b)(2), Aug. 10, 1993, 107 Stat. 555, 563, 569; Pub. L. 104–188, title I, §§ 1205(c), 1703(n)(1), Aug. 20, 1996, 110 Stat. 1775, 1877; Pub. L. 105–34, title VII, § 701(b)(1), title X, § 1083(a), Aug. 5, 1997, 111 Stat. 869, 951; Pub. L. 105–206, title VI, § 6010(n), July 22, 1998, 112 Stat. 816; Pub. L. 106–554, § 1(a)(7) [title I, § 121(b)(2)], Dec. 21, 2000, 114 Stat. 2763, 2763A–610; Pub. L. 107–16, title VI, § 619(c)(1), June 7, 2001, 115 Stat. 110; Pub. L. 108–357, title II, § 245(b)(1), title III, § 341(c), Oct. 22, 2004, 118 Stat. 1447, 1487; Pub. L. 109–135, title IV, § 412(g), Dec. 21, 2005, 119 Stat. 2637; Pub. L. 111–240, title II, § 2012(a), (b), Sept. 27, 2010, 124 Stat. 2554; Pub. L. 115–141, div. U, title IV, § 401(b)(5)(E), (F), Mar. 23, 2018, 132 Stat. 1202; Pub. L. 117–169, title I, § 13801(d), Aug. 16, 2022, 136 Stat. 2012.)
Cross-references
Computed from the citations in the text of Title 26 and 26 CFR.
This section cites 2 other sections
Cited by 15 Code sections
- § 38(c)(2)(A)(i) General business credit
- § 40(e)(2) Alcohol, etc., used as fuel
- § 41(g)(4) Credit for increasing research activities
- § 42(j)(4)(A) Low-income housing credit
- § 45A(d)(2) Indian employment credit
- § 45D(g)(4)(A) New markets tax credit
- § 45F(d)(4)(A) Employer-provided child care credit
- § 48(d)(2)(B) Energy credit
- § 50(a)(5) Other special rules
- § 196(a) Deduction for certain unused business credits
- § 383(a)(2)(A) Special limitations on certain excess credits, etc.
- § 1374(b)(3)(B) Tax imposed on certain built-in gains
- § 6411(a) Tentative carryback and refund adjustments
- § 6418(f)(1)(C) Transfer of certain credits
- § 6511(d)(4)(C) Limitations on credit or refund
Cited in 28 regulations not issued under it
- § 1.43-1 The enhanced oil recovery credit—general rules.
- § 1.46-1 Determination of amount.
- § 1.48-13 Rules relating to the increased credit amount for prevailing wage and apprenticeship.
- § 1.48-15 Election to treat clean hydrogen production facility as energy property.
- § 1.48E-4 Rules of general application.
- § 1.50-2 Recapture of the advanced manufacturing investment credit in the case of certain expansions.
- § 1.50A-3 Recomputation of credit allowed by section 40.
- § 1.72-17 Special rules applicable to owner-employees.
- § 1.367(a)-6T Transfer of foreign branch with previously deducted losses (temporary).
- § 1.382-2 General rules for ownership change.
- § 1.382-2T Definition of ownership change under section 382, as amended by the Tax Reform Act of 1986 (temporary).
- § 1.383-1 Special limitations on certain capital losses and excess credits.
- § 1.871-7 Taxation of nonresident alien individuals not engaged in U.S. business.
- § 1.871-8 Taxation of nonresident alien individuals engaged in U.S. business or treated as having effectively connected income.
- § 1.881-2 Taxation of foreign corporations not engaged in U.S. business.
- § 1.882-1 Taxation of foreign corporations engaged in U.S. business or of foreign corporations treated as having effectively connected income.
- § 1.932-1 Coordination of United States and Virgin Islands income taxes.
- § 1.935-1 Coordination of individual income taxes with Guam and the Northern Mariana Islands.
- § 1.6014-2 Tax not computed by taxpayer for taxable years beginning after December 31, 1969.
- § 1.6417-1 Elective payment election of applicable credits.
- § 1.6418-1 Transfer of eligible credits.
- § 1.6418-5 Special rules.
- § 48.6420-5 Applicable laws.
- § 48.6421-3 Time for filing claim for credit or payment.
Show 4 more
- § 48.6421-6 Applicable laws.
- § 48.6427-1 Credit or payments to purchaser of special fuels resold or used for nontaxable, farming, or other purposes.
- § 48.6427-3 Time for filing claim for credit or payment.
- § 601.105 Examination of returns and claims for refund, credit or abatement; determination of correct tax liability.
Amendment history
From the source credit and the official notes, newest first.
- Amended by Pub. L. 117–169Parts changed in 2022: (a)(4)
- Amended by Pub. L. 115–141Parts changed in 2018: (a)(3)(A) (a)(4)
- Amended by Pub. L. 111–240Parts changed in 2010: (a)(3)(A) (a)(4)
- Amended by Pub. L. 109–135Parts changed in 2005: (a)(1)(A) (a)(3)(B)
- Amended by Pub. L. 108–357Parts changed in 2004: (a)(3) (d)
- Amended by Pub. L. 107–16Parts changed in 2001: (d)(10)
- Amended by Pub. L. 106–554Parts changed in 2000: (d)(9)
- Amended by Pub. L. 105–206Parts changed in 1998: (a)(2)
- Amended by Pub. L. 105–34Parts changed in 1997: (a)(1) (a)(2) (d)(8)
- Amended by Pub. L. 104–188Parts changed in 1996: (d)(5) (d)(6) (d)(7)
- Amended by Pub. L. 103–66Parts changed in 1993: (d)(4) (d)(5) (d)(6)
- Amended by Pub. L. 102–486Parts changed in 1992: (d)
- Amended by Pub. L. 101–508Parts changed in 1990: (d)(1) (d)(5)
- Amended by Pub. L. 100–647Parts changed in 1988: (d)(4)
- Amended by Pub. L. 99–514Parts changed in 1986: (d)(1)(A) (d)(2)(B) (d)(3)
- Added by Pub. L. 98–369
Where it sits in the Code
- Subtitle A Income Taxes
- Chapter 1 NORMAL TAXES AND SURTAXES
- Subchapter A Determination of Tax Liability
- Part IV CREDITS AGAINST TAX
- Subpart D Business Related Credits
Nearby sections
- § 38 General business credit
- § 39 Carryback and carryforward of unused credits
- § 40 Alcohol, etc., used as fuel
- § 40A Biodiesel and renewable diesel used as fuel
- § 40B Sustainable aviation fuel credit
- § 41 Credit for increasing research activities
Official notes
Show the Law Revision Counsel's notes (amendments, effective dates)
Editorial Notes
Prior Provisions
A prior section 39 was renumbered section 34 of this title.
Another prior section 39 was renumbered section 37 of this title.
Amendments
2022—Subsec. (a)(4). Pub. L. 117–169 added par. (4).
2018—Subsec. (a)(3)(A). Pub. L. 115–141, § 401(b)(5)(F), struck out “or the eligible small business credits” after “gas well production credit)”.
Subsec. (a)(4). Pub. L. 115–141, § 401(b)(5)(E), struck out par. (4) which related to 5-year carryback for eligible small business credits.
2010—Subsec. (a)(3)(A). Pub. L. 111–240, § 2012(b), inserted “or the eligible small business credits” after “credit)”.
Subsec. (a)(4). Pub. L. 111–240, § 2012(a), added par. (4).
2005—Subsec. (a)(1)(A). Pub. L. 109–135, § 412(g)(1), substituted “the taxable year” for “each of the 1 taxable years”.
Subsec. (a)(3)(B). Pub. L. 109–135, § 412(g)(2), amended subpar. (B) generally. Prior to amendment, subpar. (B) read as follows: “paragraph (1) shall be applied by substituting ‘5 taxable years’ for ‘1 taxable years’ in subparagraph (A) thereof, and”.
2004—Subsec. (a)(3). Pub. L. 108–357, § 341(c), added par. (3).
Subsec. (d). Pub. L. 108–357, § 245(b)(1), amended heading and text of subsec. (d) generally, substituting provisions prohibiting carryback of the unused business credit attributable to a credit specified in section 38(b) for provisions prohibiting carryback of the enhanced oil recovery credit before 1991, sections 44, 45A, and 45B credits before their enactments, the renewable electricity production credit before its effective date, the empowerment zone employment credit, section 45C credit before July 1, 1996, DC Zone credits before their effective date, the new markets tax credit before Jan. 1, 2001, and the small employer pension plan startup cost credit before Jan. 1, 2002.
2001—Subsec. (d)(10). Pub. L. 107–16, § 619(c)(1), added par. (10).
2000—Subsec. (d)(9). Pub. L. 106–554 added par. (9).
1998—Subsec. (a)(2). Pub. L. 105–206 amended Pub. L. 105–34, § 1083(a)(2). See 1997 Amendment note below.
1997—Subsec. (a)(1). Pub. L. 105–34, § 1083(a)(1), substituted “1-year” for “3-year” and “20-year” for “15-year” in heading, “1 taxable” for “3 taxable” in subpar. (A), and “20 taxable” for “15 taxable” in subpar. (B).
Subsec. (a)(2). Pub. L. 105–34, § 1083(a)(2), as amended by Pub. L. 105–206, § 6010(n), in subpar. (A), substituted “21 taxable” for “18 taxable”, and in subpar. (B), substituted “20 years” for “17 years” in heading and “20 taxable” for “17 taxable” in text.
Subsec. (d)(8). Pub. L. 105–34, § 701(b)(1), added par. (8).
1996—Subsec. (d)(5). Pub. L. 104–188, § 1703(n)(1)(A), substituted “45A” for “45” in heading.
Subsec. (d)(6). Pub. L. 104–188, § 1703(n)(1)(B), substituted “45B” for “45” in heading.
Subsec. (d)(7). Pub. L. 104–188, § 1205(c), added par. (7).
1993—Subsec. (d)(4). Pub. L. 103–66, § 13302(a)(2), added par. (4).
Subsec. (d)(5). Pub. L. 103–66, § 13322(d), added par. (5).
Subsec. (d)(6). Pub. L. 103–66, § 13443(b)(2), added par. (6).
1992—Subsec. (d). Pub. L. 102–486 redesignated par. (5), relating to carryback of enhanced oil recovery credit, as (1), redesignated par. (5), relating to carryback of section 44 credit, as (2), and added par. (3).
1990—Subsec. (d)(1) to (4). Pub. L. 101–508, § 11801(a)(2), struck out par. (1) which related to carryforwards from an unused credit year which did not expire before first taxable year beginning after Dec. 31, 1983, par. (2) which related to carrybacks in determining amount allowable as credit including net tax liability, par. (3) which related to similar rules for research credit under section 30, and par. (4) which provided for no carryback of low-income housing credit before 1987.
Subsec. (d)(5). Pub. L. 101–508, § 11611(b)(2), added par. (5) relating to carryback of section 44 credit.
Pub. L. 101–508, § 11511(b)(2), added par. (5) relating to carryback of enhanced oil recovery credit.
1988—Subsec. (d)(4). Pub. L. 100–647 added par. (4).
1986—Subsec. (d)(1)(A). Pub. L. 99–514, § 1846(1), inserted “(as in effect before the enactment of the Tax Reform Act of 1984)”.
Subsec. (d)(2)(B). Pub. L. 99–514, § 1846(2), substituted “as defined in section 26(b)” for “as so defined in section 25(b)”.
Subsec. (d)(3). Pub. L. 99–514, § 231(d)(3)(C)(i), added par. (3).
Statutory Notes and Related Subsidiaries
Effective Date of 2022 Amendment
Amendment by Pub. L. 117–169 applicable to taxable years beginning after Dec. 31, 2022, see section 13801(g) of Pub. L. 117–169, set out as an Effective Date note under section 6417 of this title.
Effective Date of 2010 Amendment
Pub. L. 111–240, title II, § 2012(c), Sept. 27, 2010, 124 Stat. 2554, provided that: “The amendments made by this section [amending this section] shall apply to credits determined in taxable years beginning after December 31, 2009.”
Effective Date of 2004 Amendment
Pub. L. 108–357, title II, § 245(b)(2), Oct. 22, 2004, 118 Stat. 1448, provided that: “The amendment made by paragraph (1) [amending this section] shall apply with respect to taxable years ending after December 31, 2003.”
Amendment by section 245(b) of Pub. L. 108–357 applicable to taxable years beginning after Dec. 31, 2004, see section 245(e) of Pub. L. 108–357, set out as a note under section 38 of this title.
Amendment by section 341(c) of Pub. L. 108–357 applicable to production in taxable years beginning after Dec. 31, 2004, see section 341(e) of Pub. L. 108–357, set out as a note under section 38 of this title.
Effective Date of 2001 Amendment
Amendment by Pub. L. 107–16 applicable to costs paid or incurred in taxable years beginning after Dec. 31, 2001, with respect to qualified employer plans first effective after such date, see section 619(d) of Pub. L. 107–16, set out as a note under section 38 of this title.
Effective Date of 2000 Amendment
Amendment by Pub. L. 106–554 applicable to investments made after Dec. 31, 2000, see § 1(a)(7) [title I, § 121(e)] of Pub. L. 106–554, set out as a note under section 38 of this title.
Effective Date of 1998 Amendment
Amendment by Pub. L. 105–206 effective, except as otherwise provided, as if included in the provisions of the Taxpayer Relief Act of 1997, Pub. L. 105–34, to which such amendment relates, see section 6024 of Pub. L. 105–206, set out as a note under section 1 of this title.
Effective Date of 1997 Amendment
Pub. L. 105–34, title VII, § 701(d), Aug. 5, 1997, 111 Stat. 869, provided that: “Except as provided in subsection (c) [amending table of subchapters for this chapter], the amendments made by this section [enacting subchapter W of this chapter and amending this section and section 1016 of this title] shall take effect on the date of the enactment of this Act [Aug. 5, 1997].”
Pub. L. 105–34, title X, § 1083(b), Aug. 5, 1997, 111 Stat. 951, provided that: “The amendments made by this section [amending this section] shall apply to credits arising in taxable years beginning after December 31, 1997.”
Effective Date of 1996 Amendment
Amendment by section 1205(c) of Pub. L. 104–188 applicable to amounts paid or incurred in taxable years ending after June 30, 1996, see section 1205(e) of Pub. L. 104–188, set out as a note under section 45K of this title.
Pub. L. 104–188, title I, § 1703(o), Aug. 20, 1996, 110 Stat. 1878, provided that: “Any amendment made by this section [amending this section and sections 40, 59, 108, 117, 135, 143, 163, 904, 956A, 958, 1017, 1044, 1201, 1245, 1297, 1394, 1397B, 1561, 4001, 6033, 6427, 6501, 6655, and 9502 of this title, renumbering section 6714 of this title as section 6715, and amending provisions set out as notes under sections 38, 42, 197, and 1258 of this title and section 401 of Title 42, The Public Health and Welfare] shall take effect as if included in the provision of the Revenue Reconciliation Act of 1993 [Pub. L. 103–66, title XIII, ch. I, §§ 13001–13444] to which such amendment relates.”
Effective Date of 1993 Amendment
Amendment by section 13322(d) of Pub. L. 103–66 applicable to wages paid or incurred after Dec. 31, 1993, see section 13322(f) of Pub. L. 103–66, set out as a note under section 38 of this title.
Amendment by section 13443(b)(2) of Pub. L. 103–66 applicable with respect to taxes paid after Dec. 31, 1993, with respect to services performed before, on, or after such date, see section 13443(d) of Pub. L. 103–66, as amended, set out as a note under section 38 of this title.
Effective Date of 1992 Amendment
Amendment by Pub. L. 102–486 applicable to taxable years ending after Dec. 31, 1992, see section 1914(e) of Pub. L. 102–486, set out as a note under section 38 of this title.
Effective Date of 1990 Amendment
Amendment by section 11511(b)(2) of Pub. L. 101–508 applicable to costs paid or incurred in taxable years beginning after Dec. 31, 1990, see section 11511(d)(1) of Pub. L. 101–508, set out as an Effective Date note under section 43 of this title.
Amendment by section 11611(b)(2) of Pub. L. 101–508 applicable to expenditures paid or incurred after Nov. 5, 1990, see section 11611(e)(1) of Pub. L. 101–508, set out as a note under section 38 of this title.
Effective Date of 1988 Amendment
Amendment by Pub. L. 100–647 effective, except as otherwise provided, as if included in the provision of the Tax Reform Act of 1986, Pub. L. 99–514, to which such amendment relates, see section 1019(a) of Pub. L. 100–647, set out as a note under section 1 of this title.
Effective Date of 1986 Amendment
Amendment by section 231(d)(3)(C)(i) of Pub. L. 99–514 applicable to taxable years beginning after Dec. 31, 1985, see section 231(g) of Pub. L. 99–514, set out as a note under section 41 of this title.
Amendment by section 1846 of Pub. L. 99–514 effective, except as otherwise provided, as if included in the provisions of the Tax Reform Act of 1984, Pub. L. 98–369, div. A, to which such amendment relates, see section 1881 of Pub. L. 99–514, set out as a note under section 48 of this title.
Effective Date
Section applicable to taxable years beginning after Dec. 31, 1983, and to carrybacks from such years, see section 475(a) of Pub. L. 98–369, set out as an Effective Date of 1984 Amendment note under section 21 of this title.
Savings Provision
For provisions that nothing in amendment by Pub. L. 115–141 be construed to affect treatment of certain transactions occurring, property acquired, or items of income, loss, deduction, or credit taken into account prior to Mar. 23, 2018, for purposes of determining liability for tax for periods ending after Mar. 23, 2018, see section 401(e) of Pub. L. 115–141, set out as a note under section 23 of this title.
For provisions that nothing in amendment by section 11801(a)(2) of Pub. L. 101–508 be construed to affect treatment of certain transactions occurring, property acquired, or items of income, loss, deduction, or credit taken into account prior to Nov. 5, 1990, for purposes of determining liability for tax for periods ending after Nov. 5, 1990, see section 11821(b) of Pub. L. 101–508, set out as a note under section 45K of this title.
Plan Amendments Not Required Until January 1, 1989
For provisions directing that if any amendments made by subtitle A or subtitle C of title XI [§§ 1101–1147 and 1171–1177] or title XVIII [§§ 1800–1899A] of Pub. L. 99–514 require an amendment to any plan, such plan amendment shall not be required to be made before the first plan year beginning on or after Jan. 1, 1989, see section 1140 of Pub. L. 99–514, as amended, set out as a note under section 401 of this title.