- § 6601. Interest on underpayment, nonpayment, or extensions of time for payment, of tax
- § 6602. Interest on erroneous refund recoverable by suit
- § 6603. Deposits made to suspend running of interest on potential underpayments, etc.
§ 6601. Interest on underpayment, nonpayment, or extensions of time for payment, of tax
(a) General rule
(b) Last date prescribed for payment
For purposes of this section, the last date prescribed for payment of the tax shall be determined under chapter 62 with the application of the following rules:
(1) Extensions of time disregarded
(2) Jeopardy
(3) Accumulated earnings tax
(4) Last date for payment not otherwise prescribed
(c) Suspension of interest in certain income, estate, gift, and certain excise tax cases
(d) Income tax reduced by carryback or adjustment for certain unused deductions
(1) Net operating loss or capital loss carryback
(2) Foreign tax credit carrybacks
(3) Certain credit carrybacks
(A) In general
(B) Credit carryback defined
(4) Filing date
(e) Applicable rules
Except as otherwise provided in this title—
(1) Interest treated as tax
(2) Interest on penalties, additional amounts, or additions to the tax
(A) In general
(B) Interest on certain additions to tax
Interest shall be imposed under this section with respect to any addition to tax imposed by section 6651(a)(1) or 6653 or under part II of subchapter A of chapter 68 for the period which—
(i) begins on the date on which the return of the tax with respect to which such addition to tax is imposed is required to be filed (including any extensions), and
(ii) ends on the date of payment of such addition to tax.
(3) Payments made within specified period after notice and demand
(f) Satisfaction by credits
(g) Limitation on assessment and collection
(h) Exception as to estimated tax
(i) Exception as to Federal unemployment tax
(j) 2-percent rate on certain portion of estate tax extended under section 6166
(1) In general
If the time for payment of an amount of tax imposed by chapter 11 is extended as provided in section 6166, then in lieu of the annual rate provided by subsection (a)—
(A) interest on the 2-percent portion of such amount shall be paid at the rate of 2 percent, and
(B) interest on so much of such amount as exceeds the 2-percent portion shall be paid at a rate equal to 45 percent of the annual rate provided by subsection (a).
For purposes of this subsection, the amount of any deficiency which is prorated to installments payable under section 6166 shall be treated as an amount of tax payable in installments under such section.
(2) 2-percent portion
For purposes of this subsection, the term “2-percent portion” means the lesser of—
(A)
(i) the amount of the tentative tax which would be determined under the rate schedule set forth in section 2001(c) if the amount with respect to which such tentative tax is to be computed were the sum of $1,000,000 and the applicable exclusion amount in effect under section 2010(c), reduced by
(ii) the applicable credit amount in effect under section 2010(c), or
(B) the amount of the tax imposed by chapter 11 which is extended as provided in section 6166.
(3) Inflation adjustment
In the case of estates of decedents dying in a calendar year after 1998, the $1,000,000 amount contained in paragraph (2)(A) shall be increased by an amount equal to—
(A) $1,000,000, multiplied by
(B) the cost-of-living adjustment determined under section 1(f)(3) for such calendar year by substituting “calendar year 1997” for “calendar year 2016” in subparagraph (A)(ii) thereof.
If any amount as adjusted under the preceding sentence is not a multiple of $10,000, such amount shall be rounded to the next lowest multiple of $10,000.
(4) Treatment of payments
(k) No interest on certain adjustments
(Aug. 16, 1954, ch. 736, 68A Stat. 817; Pub. L. 85–866, title I, §§ 66(c), 83(a)(1), 84(a), title II, § 206(e), Sept. 2, 1958, 72 Stat. 1658, 1663, 1664, 1685; Pub. L. 87–61, title II, § 203(c)(2), June 29, 1961, 75 Stat. 126; Pub. L. 87–834, § 2(e)(3), Oct. 16, 1962, 76 Stat. 972; Pub. L. 88–571, § 3(d), Sept. 2, 1964, 78 Stat. 858; Pub. L. 89–384, § 1(f), Apr. 8, 1966, 80 Stat. 104; Pub. L. 90–225, § 2(e), Dec. 27, 1967, 81 Stat. 731; Pub. L. 91–53, § 2(e), Aug. 7, 1969, 83 Stat. 92; Pub. L. 91–172, title I, § 101(j)(49), title V, § 512(e)(3), Dec. 30, 1969, 83 Stat. 531, 641; Pub. L. 92–178, title VI, § 601(d)(3), Dec. 10, 1971, 85 Stat. 559; Pub. L. 93–406, title II, § 1016(a)(17), Sept. 2, 1974, 88 Stat. 930; Pub. L. 93–625, § 7(a)(2)(A), (b)(1), Jan. 3, 1975, 88 Stat. 2115; Pub. L. 94–452, § 3(c)(3), Oct. 2, 1976, 90 Stat. 1514; Pub. L. 94–455, title XIII, § 1307(d)(2)(H), title XVI, § 1605(b)(10), title XIX, §§ 1906(a)(34), (b)(13)(A), title XX, § 2004(b), title XXI, § 2107(g)(2)(C), Oct. 4, 1976, 90 Stat. 1728, 1755, 1829, 1834, 1867, 1904; Pub. L. 95–30, title II, § 202(d)(4)(C), May 23, 1977, 91 Stat. 150; Pub. L. 95–628, § 8(c)(2), Nov. 10, 1978, 92 Stat. 3632; Pub. L. 96–223, title I, § 101(f)(7), Apr. 2, 1980, 94 Stat. 253; Pub. L. 97–248, title III, §§ 344(b)(1), 346(c)(2), Sept. 3, 1982, 96 Stat. 635, 637; Pub. L. 98–76, title II, § 231(b)(2)(D), Aug. 12, 1983, 97 Stat. 429; Pub. L. 98–369, div. A, title I, § 158(a), title II, § 211(b)(26), title IV, § 412(b)(7), title VII, § 714(n)(1), July 18, 1984, 98 Stat. 696, 757, 792, 963; Pub. L. 99–514, title XIV, § 1404(c)(3), title XV, §§ 1511(c)(11), 1512(a), 1564(a), Oct. 22, 1986, 100 Stat. 2714, 2745, 2746, 2762; Pub. L. 100–203, title X, § 10301(b)(5), Dec. 22, 1987, 101 Stat. 1330–429; Pub. L. 100–647, title I, §§ 1015(b)(2)(C), 1018(u)(42), title VI, § 6234(b)(1), title VII, § 7106(c)(5), Nov. 10, 1988, 102 Stat. 3569, 3592, 3736, 3774; Pub. L. 101–239, title VII, § 7721(c)(8), Dec. 19, 1989, 103 Stat. 2400; Pub. L. 101–508, title XI, § 11801(c)(20)(B), Nov. 5, 1990, 104 Stat. 1388–528; Pub. L. 104–168, title III, § 303(a), (b)(1), July 30, 1996, 110 Stat. 1458; Pub. L. 105–34, title V, §§ 501(e), 503(a), (c)(2), (3), title X, § 1055(a), title XII, § 1242(a), Aug. 5, 1997, 111 Stat. 846, 852, 853, 944, 1029; Pub. L. 105–206, title III, § 3301(b), July 22, 1998, 112 Stat. 741; Pub. L. 109–135, title IV, § 409(a)(2), Dec. 21, 2005, 119 Stat. 2635; Pub. L. 114–74, title XI, § 1101(f)(9), Nov. 2, 2015, 129 Stat. 638; Pub. L. 115–97, title I, § 11002(d)(1)(JJ), Dec. 22, 2017, 131 Stat. 2060; Pub. L. 115–141, div. U, title IV, § 401(b)(47), Mar. 23, 2018, 132 Stat. 1204.)
§ 6602. Interest on erroneous refund recoverable by suit
Any portion of an internal revenue tax (or any interest, assessable penalty, additional amount, or addition to tax) which has been erroneously refunded, and which is recoverable by suit pursuant to section 7405, shall bear interest at the underpayment rate established under section 6621 from the date of the payment of the refund.
(Aug. 16, 1954, ch. 736, 68A Stat. 818; Pub. L. 93–625, § 7(a)(2)(B), Jan. 3, 1975, 88 Stat. 2115; Pub. L. 99–514, title XV, § 1511(c)(12), Oct. 22, 1986, 100 Stat. 2745.)
§ 6603. Deposits made to suspend running of interest on potential underpayments, etc.
(a) Authority to make deposits other than as payment of tax
(b) No interest imposed
(c) Return of deposit
(d) Payment of interest
(1) In general
(2) Disputable tax
(A) In general
(B) Safe harbor based on 30-day letter
(3) Other definitions
For purposes of paragraph (2)—
(A) Disputable item
The term “disputable item” means any item of income, gain, loss, deduction, or credit if the taxpayer—
(i) has a reasonable basis for its treatment of such item, and
(ii) reasonably believes that the Secretary also has a reasonable basis for disallowing the taxpayer’s treatment of such item.
(B) 30-day letter
(4) Rate of interest
(e) Use of deposits
(1) Payment of tax
(2) Returns of deposits
(Added Pub. L. 108–357, title VIII, § 842(a), Oct. 22, 2004, 118 Stat. 1598; amended Pub. L. 116–25, title I, § 1001(b)(1)(D), July 1, 2019, 133 Stat. 985.)