§6621 — Determination of rate of interest

Statute Text — 26 U.S.C. §6621

Treasury Regulations

• Treas. Reg. §301.6621-1Interest rate Show full text ▾ Collapse ▴

  (a) In general. The interest rate established under section 6621 shall be—

  (1) On amounts outstanding before July 1, 1975, 6 percent per annum (or 4 percent in the case of certain extensions of time for payment of taxes as provided in sections 6601 (b) and (j) prior to amendment by section 7(b) of the Act of Jan. 3, 1975 (Pub. L. 93-625, 88 Stat. 2115), and certain overpayments of the unrelated business income tax as provided in section 514(b)(3)(D), prior to its amendment by such Act).

  (2) On amounts outstanding—

  (3) On amounts outstanding after December 31, 1982, the adjusted rate established by the Commissioner under section 6621(b). This adjusted rate shall be published by the Commissioner in a Revenue Ruling. See § 301.6622-1 for application of daily compounding in determining interest accruing after December 31, 1982. Because interest accruing after December 31, 1982, accrues at the prescribed rate per annum compounded daily, the effective annual percentage rate of interest will exceed the prescribed rate of interest.

  (b) [Reserved]

  (c) Applicability of interest rate—(1) Computation. Interest and additions to tax on any amount outstanding on a specific day shall be computed at the annual rate applicable on such day.

  (2) Additions to tax. Additions to tax under any section of the Code that refers to the annual rate established under this section, including sections 644(a)(2)(B), 4497(c)(2), 6654(a), and 6655 (a) and (g), shall be computed at the same rate per annum as the interest rate set forth under paragraph (a) of this section.

  (3) Interest. Interest provided for under any section of the Code that refers to the annual rate established under this section, including sections 47(d)(3)(G), 167(q), 6332(c)(1), 6343(c), 6601(a), 6602, 6611(a), 7426(g), and section 1961(c)(1) or 2411 of title 28 of the United States Code, shall be computed at the rate per annum set forth under paragraph (a) of this section.

  (d) Examples. The provisions of this section may be illustrated by the following examples. Example 6 illustrates the computation of interest for interest accuring after December 31, 1982.

• Treas. Reg. §301.6621-1(a)In general. Show full text ▾ Collapse ▴

  In general. The interest rate established under section 6621 shall be—

  (1) On amounts outstanding before July 1, 1975, 6 percent per annum (or 4 percent in the case of certain extensions of time for payment of taxes as provided in sections 6601 (b) and (j) prior to amendment by section 7(b) of the Act of Jan. 3, 1975 (Pub. L. 93-625, 88 Stat. 2115), and certain overpayments of the unrelated business income tax as provided in section 514(b)(3)(D), prior to its amendment by such Act).

  (2) On amounts outstanding—

  (3) On amounts outstanding after December 31, 1982, the adjusted rate established by the Commissioner under section 6621(b). This adjusted rate shall be published by the Commissioner in a Revenue Ruling. See § 301.6622-1 for application of daily compounding in determining interest accruing after December 31, 1982. Because interest accruing after December 31, 1982, accrues at the prescribed rate per annum compounded daily, the effective annual percentage rate of interest will exceed the prescribed rate of interest.

• Treas. Reg. §301.6621-1(b)§301.6621-1(b) Show full text ▾ Collapse ▴

  [Reserved]

• Treas. Reg. §301.6621-1(c)Applicability of interest rate—(1) Computation. Show full text ▾ Collapse ▴

  Applicability of interest rate—(1) Computation. Interest and additions to tax on any amount outstanding on a specific day shall be computed at the annual rate applicable on such day.

  (2) Additions to tax. Additions to tax under any section of the Code that refers to the annual rate established under this section, including sections 644(a)(2)(B), 4497(c)(2), 6654(a), and 6655 (a) and (g), shall be computed at the same rate per annum as the interest rate set forth under paragraph (a) of this section.

  (3) Interest. Interest provided for under any section of the Code that refers to the annual rate established under this section, including sections 47(d)(3)(G), 167(q), 6332(c)(1), 6343(c), 6601(a), 6602, 6611(a), 7426(g), and section 1961(c)(1) or 2411 of title 28 of the United States Code, shall be computed at the rate per annum set forth under paragraph (a) of this section.

• Treas. Reg. §301.6621-1(d)Examples. Show full text ▾ Collapse ▴

  Examples. The provisions of this section may be illustrated by the following examples. Example 6 illustrates the computation of interest for interest accuring after December 31, 1982.

• Treas. Reg. §301.6621-2TQuestions and answers relating to the increased rate of interest on substantial underpayments attributable to certain tax motivated transactions Show full text ▾ Collapse ▴

  The following questions and answers relate to the increased rate of interest on substantial underpayments attributable to certain tax motivated transactions as provided in section 6621(d) of the Internal Revenue Code of 1954, as added by section 144 of the Tax Reform Act of 1984 (Pub. L. 98-369, 98 Stat. 682):

  Q-1. What is the annual interest rate under section 6621 for purposes of computing the amount of interest that must be paid under section 6601 (relating to interest on underpayments)?

  A-1. In general, the annual interest rate for purposes of section 6601 is the adjusted rate of interest established under section 6621 (b) § 301.6621-1 (“adjusted rate”). If, however, a tax motivated underpayment (as defined in A-2 of this section) for a taxable year is substantial (as defined in A-7 of this section), section 6621(d) provides that the annual rate of interest with respect to the tax motivated underpayment is 120 percent of the adjusted rate (“120 percent rate”), rounded to the nearest tenth of a percent.

  Q-2. What is a tax motivated underpayment?

  A-2. A tax motivated underpayment is the portion of a deficiency (as defined in section 6211) of tax imposed by subtitle A (income taxes) that is attributable to any of the following tax motivated transactions:

  (1) Any instance in which the value of any property, or the adjusted basis of any property, claimed on a return is 150 percent or more of the amount determined to be the correct amount of such valuation or adjusted basis (i.e., a valuation overstatement within the meaning of section 6659(c)(1));

  (2) Any loss disallowed for any period by reason of section 465(a) or any amount included in gross income by reason of section 465(e);

  (3) Any credit disallowed for any period by reason of section 46(c)(8) or section 48(d)(6);

  (4) Any loss disallowed for any period with respect to a straddle, as defined in section 1092(c), but without regard to sections 1092 (d) and (e);

  (5) Any use of an accounting method that may result in a substantial distortion of income for any period (see A-3 of this section); and

  (6) Any deduction disallowed with respect to any other tax motivated transactions (see A-4 of this section).

  Q-3. What accounting methods may result in a substantial distortion of income for any period under A-2(5) of this section?

  A-3. A deduction or credit disallowed, or income included, in any of the circumstances listed below shall be treated as attributable to the use of an accounting method that may result in a substantial distortion of income and shall thus be a tax motivated transaction that results in a tax motivated underpayment:

  (1) Any deduction disallowed for any period by reason of section 464 or section 278(b), relating to certain expenses of farming syndicates;

  (2) In the case of a taxpayer who computes taxable income using the cash receipts and disbursements method of accounting, any interest deduction disallowed for any period by reason of section 461(g), relating to prepaid interest, provided the interest is not paid with respect to indebtedness incurred in connection with (i) the purchase, refinancing, or improvement of the principal residence of the taxpayer, or (ii) the purchase of consumer goods by the taxpayer;

  (3) Any interest deduction disallowed for any period because the amount of the claimed deduction was computed using a method resulting in an amount of interest for a period that exceeds the true cost of the indebtedness for the period computed by applying the effective rate of interest on the loan to the unpaid balance of the loan for the period (i.e., the economic accrual of interest for the period), provided the interest is not accrued with respect to indebtedness incurred in connection with (i) the purchase, refinancing, or improvement of the principal residence of the taxpayer, or (ii) the purchase of consumer goods by the taxpayer (see Rev. Rul. 83-84, 1983-1 C.B. 97, and sections 163(e), 446(b), and 483);

  (4) Any deduction disallowed for any period under section 709, relating to organization or syndication expenditures of a partnership;

  (5) In the case of any expenditure described in section 248(b) that was incurred by an S corporation, any deduction disallowed because it exceeds the amount allowable under section 248, relating to organizational expenditures;

  (6) Any deduction disallowed for any period under section 267(a), relating to transactions between related taxpayers;

  (7) Any deduction disallowed for any period, or any income required to be included for any period, under section 467, relating to certain payments for the use of property or services;

  (8) Any deduction disallowed for any period under section 461(i), relating to certain deductions of tax shelters; and

  (9) In the case of a taxpayer who computes taxable income using the cash receipts and disbursements method of accounting, any deduction disallowed for any period because (i) the expenditure resulting in the deduction was a deposit rather than a payment, (ii) the expenditure was prepaid for tax avoidance purposes and not for a business purpose, or (iii) the deduction resulted in a material distortion of income (see, e.g., Rev. Rul. 79-229, 1979-2 C.B. 210).

  Q-4. Are any transaction other than those specified in A-2 of this section and those involving the use of accounting methods under circumstances specified in A-3 of this section considered tax motivated transactions under A-2(6) of this section?

  A-4. Yes. Deductions disallowed under the following provisions are considered to be attributable to tax motivated transactions:

  (1) Any deduction disallowed for any period under section 183, relatiing to an activity engaged in by an individual or an S corporation that is not engaged in for profit, and

  (2) Any deduction disallowed for any period under section 165(c)(2), relating to any transaction not entered into for profit.

  Q-5. How is the amount of a tax motivated underpayment determined?

  A-5. Except as provided in A-6 of this section, the amount of a tax motivated underpayment is determined in the following manner:

  (1) Calculate the amount of the tax liability for the taxable year as if all items of income, gain, loss, deduction, or credit, had been reported properly on the income tax return of the taxpayer (“total tax liability”); and

  (2) Without taking into account any adjustments to items of income, gain, loss, deduction, or credit that are attributable to tax motivated transactions (as defined in A-2 through A-4 of this section), calculate the amount of the tax liability for the taxable year as if all other items of income, gain loss, deduction, or credit had been reported properly on the income tax return of the taxpayer (“tax liability without regard to tax motivated transactions”).

  (3) The difference between the total tax liability and the tax liability without regard to tax motivated transactions is the amount of the tax motivated underpayment.

  Q-6: How are the amounts of the tax motivated underpayment and the underpayment attributable to fraud or negligence determined if all or a portion of the taxpayer's underpayment is attributable to one or more tax motivated transactions and all or a portion is subject to the addition to tax imposed by section 6653(a)(2) (in the case of an underpayment attributable to negligence or intentional disregard) or section 6653(b)(2) (in the case of an underpayment attributable to fraud)?

  A-6: If all or a portion of the taxpayer's underpayment is attributable to tax motivated transactions, and all or a portion is attributable to fraudulent or negligent items (i.e., items that result in an underpayment subject to the addition to tax imposed by section 6653 (a)(2) or (b)(2)), the amount of the tax motivated underpayment and the underpayment attributable to fraud or negligence is determined in the following manner:

  (1) Determine the following amounts;

  (i) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit had been reported properly on the income tax return of the taxpayer (“total tax liability”);

  (ii) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit without taking into account adjustments to items of income, gain, loss, deduction, or credit that are both (a) attributable to tax motivated transactions and (b) subject to section 6653(a)(2) or section 6653(b)(2), had been reported properly on the income tax return of the taxpayer (“tax liability without regard to fraudulent or negligent tax motivated items”);

  (iii) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit, without taking into account adjustments to items of income, gain, loss, deduction, or credit that are subject to section 6653(a)(2) or section 6653(b)(2), had been reported properly on the income tax return of the taxpayer (“tax liability without regard to fraudulent or negligent items”);

  (iv) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit, without taking into account adjustments to items of income, gain, loss, deduction, or credit that are either subject to section 6653(a)(2) or section 6653(b)(2) or attributable to tax motivated transactions, had been reported properly on the income tax return of the taxpayer (“tax liability without regard to tax motivated or fraudulent or negligent items”).

  (2) The tax motivated underpayment attributable to fraudulent or negligent items is the excess of the total tax liability over the tax liability determined without regard to fraudulent or negligent tax motivated items ((i)-(ii)).

  (3) The tax motivated underpayment is the sum of (a) the tax motivated underpayment attributable to fraudulent or negligent items ((i)-(ii)) plus (b) the excess of the tax liability without regard to fraudulent or negligent items over the tax liability without regard to tax motivated or fraudulent or negligent items ((iii)-(iv)). Interest on this underpayment is computed at the 120 percent rate.

  (4) The underpayment attributable to fraudulent or negligent items is the excess of the total tax liability over the tax liability without regard to fraudulent or negligent items ((i)-(iii)). The section 6653 addition to tax is 50 percent of the interest on this underpayment computed at the 120 percent rate on an amount equal to the tax motivated underpayment attributable to fraudulent or negligent items (computed in (2)) and at the adjusted rate on the remainder.

  (2) The tax motivated underpayment attributable to fraudulent or negligent items is $2,500 ((i))-(ii) or $39,685−$37,185).

  (3) The tax motivated underpayment is $10,844 ((2) + ((iii)-(iv)) or $2,500 + ($33,435−$25,091)). Interest on $10,844 is computed at the 120 percent rate.

  (4) The underpayment attributable to fraudulent or negligent items is $6,250 ((i)-(iii) or $39,685−$33,435). The section 6653 addition to tax is 50 percent of the interest on $6,250, computed at the 120 percent rate on an amount equal to the tax motivated underpayment attributable to fraudulent or negligent items ($2,500) and at the adjusted rate on the remainder ($3,750).

  (5) In summary, therefore, the total underpayment is $16,514 (total tax liability ($39,685) less reported tax liability ($23,171)) of which $10,844 accrues interest at the 120 percent rate and $5,670 ($16,514−$10,844) accrues interest at the adjusted rate. In addition, $6,250 of the underpayment is subject to the section 6653(a)(2) or section 6653(b)(2) addition to tax. The underlying interest, upon which the addition to tax is based, is computed using the 120 percent rate for the portion of the underpayment subject to section 6621(d) ($2,500) and the adjusted rate for the portion that is not subject to section 6621(d) ($3,750).

  Q-7. Does the 120 percent rate apply to all tax motivated underpayments?

  A-7. No. The 120 percent rate applies only if the tax motivated underpayment for the taxable year is substantial. A tax motivated underpayment is substantial only if it exceeds $1,000. If, for example, a taxpayer has a $600 underpayment attributable to a valuation overstatement (within the meaning of section 6659(c)(1)) and a $500 underpayment attributable to a loss disallowed under section 465(a), the amount of the tax motivated underpayment is $1,100. Because the amount of the tax motivated underpayment is thus substantial the 120 percent rate applies.

  Q-8. How do carryovers affect the amount of the tax motivated underpayment and the amount of the underpayment attributable to fraudulent or negligent items?

  A-8. For purposes of A-5 and A-6 of this section, a net operating loss carryover, capital loss carryover, or credit carryover is treated as a deduction or credit in the year in which taken into account. In any computation of tax liability required under A-5 or A-6 of this section (i.e., total tax liability, tax liability without regard to tax motivated transactions, etc.), the amount of such deduction or credit is the amount of the carryover determined as if the taxpayer had properly reported in each taxable year all items of income, gain, loss, deduction, or credit affecting the amount of the carryover other than adjustments of a type not taken into account in such computation of tax liability. A net operating loss carryback, capital loss carryback, or credit carryback is not taken into account, however, in determining the amount of the tax motivated underpayment or the amount of the underpayment attributable to fraud or negligence for periods before the last date prescribed for filing the income tax return for the taxable year in which the carryback arises (determined without regard to extensions).

  Q-9. What amount is subject to the 120 percent rate if the amount of a taxpayer's unpaid tax for a year is less than the taxpayer's substantial tax motivated underpayment?

  A-9. The 120 percent rate applies with respect to the lesser of—

  (1) The amount of unpaid tax for the taxable year determined in accordance with § 301.6601-1; or

  (2) The substantial tax motivated underpayment for the taxable year.

  Q-10. What is the effective date for the 120 percent rate?

  A-10. The 120 percent rate applies to interest accruing on a deficiency attributable to a substantial tax motivated underpayment after December 31, 1984, including interest accruing with respect to transactions described in A-3 and A-4 of this section, regardless of the date prescribed for payment of the tax.

  Q-11. Can a taxpayer stop the running of interest on a tax motivated underpayment by application of a remittance?

  A-11. Yes. The running of interest on a tax liability stops on the date the remittance (either a payment of tax or a deposit in the nature of a cash bond) is received by the Internal Revenue Service, regardless of when the liability is assessed or the remittance is actually applied against the taxpayer's account. A taxpayer must make a remittance for both the tax liability and the interest that has accrued as of the date of remittance to stop the running of interest on both the tax liability and the accrued interest with respect to the liability. (See Rev. Proc. 84-58.) Taxpayer cannot make partial remittances applicable only to tax motivated underpayments. Under A-9 of this section, the 120 percent rate applies to the amount of unpaid tax to the extent that amount does not exceed the tax motivated underpayment. Therefore, a partial remittance is applied first to any tax due that is not attributable to a tax motivated underpayment. The excess of the partial remittance over tax that is not attributable to a tax motivated underpayment, if any, will then be applied to tax due that is attributable to a tax motivated underpayment.

  Q-12. Does the 120 percent rate apply to interest accruing on interest, penalties, additional amounts, or additions to tax as provided in section 6601(e)(2)?

  A-12. The 120 percent rate applies only to taxes imposed by subtitle A (income taxes) and to interest accrued with respect to such taxes. The penalties, additional amounts, and additions to tax specified in section 6601(e)(2) are not imposed by subtitle A and are not, therefore, included in the amount of a tax motivated underpayment. They are, however, included in the amount of unpaid tax for purposes of A-9 of this section.

• Treas. Reg. §301.6621-2T(i)§301.6621-2T(i) Show full text ▾ Collapse ▴

  The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit had been reported properly on the income tax return of the taxpayer (“total tax liability”);

  (ii) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit without taking into account adjustments to items of income, gain, loss, deduction, or credit that are both (a) attributable to tax motivated transactions and (b) subject to section 6653(a)(2) or section 6653(b)(2), had been reported properly on the income tax return of the taxpayer (“tax liability without regard to fraudulent or negligent tax motivated items”);

  (iii) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit, without taking into account adjustments to items of income, gain, loss, deduction, or credit that are subject to section 6653(a)(2) or section 6653(b)(2), had been reported properly on the income tax return of the taxpayer (“tax liability without regard to fraudulent or negligent items”);

  (iv) The tax liability for the taxable year of the taxpayer as if all items of income, gain, loss, deduction, or credit, without taking into account adjustments to items of income, gain, loss, deduction, or credit that are either subject to section 6653(a)(2) or section 6653(b)(2) or attributable to tax motivated transactions, had been reported properly on the income tax return of the taxpayer (“tax liability without regard to tax motivated or fraudulent or negligent items”).

  (2) The tax motivated underpayment attributable to fraudulent or negligent items is the excess of the total tax liability over the tax liability determined without regard to fraudulent or negligent tax motivated items ((i)-(ii)).

  (3) The tax motivated underpayment is the sum of (a) the tax motivated underpayment attributable to fraudulent or negligent items ((i)-(ii)) plus (b) the excess of the tax liability without regard to fraudulent or negligent items over the tax liability without regard to tax motivated or fraudulent or negligent items ((iii)-(iv)). Interest on this underpayment is computed at the 120 percent rate.

  (4) The underpayment attributable to fraudulent or negligent items is the excess of the total tax liability over the tax liability without regard to fraudulent or negligent items ((i)-(iii)). The section 6653 addition to tax is 50 percent of the interest on this underpayment computed at the 120 percent rate on an amount equal to the tax motivated underpayment attributable to fraudulent or negligent items (computed in (2)) and at the adjusted rate on the remainder.

  (2) The tax motivated underpayment attributable to fraudulent or negligent items is $2,500 ((i))-(ii) or $39,685−$37,185).

  (3) The tax motivated underpayment is $10,844 ((2) + ((iii)-(iv)) or $2,500 + ($33,435−$25,091)). Interest on $10,844 is computed at the 120 percent rate.

  (4) The underpayment attributable to fraudulent or negligent items is $6,250 ((i)-(iii) or $39,685−$33,435). The section 6653 addition to tax is 50 percent of the interest on $6,250, computed at the 120 percent rate on an amount equal to the tax motivated underpayment attributable to fraudulent or negligent items ($2,500) and at the adjusted rate on the remainder ($3,750).

  (5) In summary, therefore, the total underpayment is $16,514 (total tax liability ($39,685) less reported tax liability ($23,171)) of which $10,844 accrues interest at the 120 percent rate and $5,670 ($16,514−$10,844) accrues interest at the adjusted rate. In addition, $6,250 of the underpayment is subject to the section 6653(a)(2) or section 6653(b)(2) addition to tax. The underlying interest, upon which the addition to tax is based, is computed using the 120 percent rate for the portion of the underpayment subject to section 6621(d) ($2,500) and the adjusted rate for the portion that is not subject to section 6621(d) ($3,750).

  Q-7. Does the 120 percent rate apply to all tax motivated underpayments?

  A-7. No. The 120 percent rate applies only if the tax motivated underpayment for the taxable year is substantial. A tax motivated underpayment is substantial only if it exceeds $1,000. If, for example, a taxpayer has a $600 underpayment attributable to a valuation overstatement (within the meaning of section 6659(c)(1)) and a $500 underpayment attributable to a loss disallowed under section 465(a), the amount of the tax motivated underpayment is $1,100. Because the amount of the tax motivated underpayment is thus substantial the 120 percent rate applies.

  Q-8. How do carryovers affect the amount of the tax motivated underpayment and the amount of the underpayment attributable to fraudulent or negligent items?

  A-8. For purposes of A-5 and A-6 of this section, a net operating loss carryover, capital loss carryover, or credit carryover is treated as a deduction or credit in the year in which taken into account. In any computation of tax liability required under A-5 or A-6 of this section (i.e., total tax liability, tax liability without regard to tax motivated transactions, etc.), the amount of such deduction or credit is the amount of the carryover determined as if the taxpayer had properly reported in each taxable year all items of income, gain, loss, deduction, or credit affecting the amount of the carryover other than adjustments of a type not taken into account in such computation of tax liability. A net operating loss carryback, capital loss carryback, or credit carryback is not taken into account, however, in determining the amount of the tax motivated underpayment or the amount of the underpayment attributable to fraud or negligence for periods before the last date prescribed for filing the income tax return for the taxable year in which the carryback arises (determined without regard to extensions).

  Q-9. What amount is subject to the 120 percent rate if the amount of a taxpayer's unpaid tax for a year is less than the taxpayer's substantial tax motivated underpayment?

  A-9. The 120 percent rate applies with respect to the lesser of—

  (1) The amount of unpaid tax for the taxable year determined in accordance with § 301.6601-1; or

  (2) The substantial tax motivated underpayment for the taxable year.

  Q-10. What is the effective date for the 120 percent rate?

  A-10. The 120 percent rate applies to interest accruing on a deficiency attributable to a substantial tax motivated underpayment after December 31, 1984, including interest accruing with respect to transactions described in A-3 and A-4 of this section, regardless of the date prescribed for payment of the tax.

  Q-11. Can a taxpayer stop the running of interest on a tax motivated underpayment by application of a remittance?

  A-11. Yes. The running of interest on a tax liability stops on the date the remittance (either a payment of tax or a deposit in the nature of a cash bond) is received by the Internal Revenue Service, regardless of when the liability is assessed or the remittance is actually applied against the taxpayer's account. A taxpayer must make a remittance for both the tax liability and the interest that has accrued as of the date of remittance to stop the running of interest on both the tax liability and the accrued interest with respect to the liability. (See Rev. Proc. 84-58.) Taxpayer cannot make partial remittances applicable only to tax motivated underpayments. Under A-9 of this section, the 120 percent rate applies to the amount of unpaid tax to the extent that amount does not exceed the tax motivated underpayment. Therefore, a partial remittance is applied first to any tax due that is not attributable to a tax motivated underpayment. The excess of the partial remittance over tax that is not attributable to a tax motivated underpayment, if any, will then be applied to tax due that is attributable to a tax motivated underpayment.

  Q-12. Does the 120 percent rate apply to interest accruing on interest, penalties, additional amounts, or additions to tax as provided in section 6601(e)(2)?

  A-12. The 120 percent rate applies only to taxes imposed by subtitle A (income taxes) and to interest accrued with respect to such taxes. The penalties, additional amounts, and additions to tax specified in section 6601(e)(2) are not imposed by subtitle A and are not, therefore, included in the amount of a tax motivated underpayment. They are, however, included in the amount of unpaid tax for purposes of A-9 of this section.

• Treas. Reg. §301.6621-3Higher interest rate payable on large corporate underpayments Show full text ▾ Collapse ▴

  (a) In general. Section 6621 establishes the interest rate for purposes of computing the amount of interest that must be paid under section 6601, relating to interest on underpayments of tax. Section 6621(a)(2) provides that the underpayment rate is the sum of the Federal short-term rate (determined under section 6621(b)) plus 3 percentage points. That underpayment rate is referred to hereinafter as the “section 6621(a)(2) rate.” Section 6621(c) and this section, however, provide that the underpayment rate on any large corporate underpayment is the sum of the Federal short-term rate (determined under section 6621(b)) plus 5 percentage points. This higher underpayment rate is referred to hereinafter as the “section 6621(c) rate.” The section 6621(c) rate applies only for periods after the applicable date (as determined in paragraph (c) of this section).

  (b) Large corporate underpayment—(1) Defined. For purposes of section 6621(c) and this section, “large corporate underpayment” means any underpayment of a tax by a C corporation for any taxable period if the amount of the threshold underpayment of the tax (as defined in paragraph (b)(2)(ii) of this section) for that taxable period exceeds $100,000.

  (2) Underpayment of a tax—(i) In general. As used in section 6621(c) and this section, “underpayment of a tax” means the excess of a tax imposed by the Internal Revenue Code over the amount of such tax paid on or before the last date prescribed for payment. Except as provided in paragraph (b)(2)(ii) of this section, “tax” for such purposes includes interest, penalties, additional amounts, and additions to tax. See sections 6601(e)(1), 6665(a), and 6671(a). Thus, the section 6621(c) rate generally applies to any interest, penalties, additional amounts, and additions to tax, as well as to the underlying tax with respect to which such amounts are imposed.

  (ii) Threshold underpayment of a tax. Solely for purposes of this section and not for any other purpose under section 6621(c) or elsewhere in the interpretation or administration of the federal tax laws, a “threshold underpayment of a tax” is the excess of a tax imposed by the Internal Revenue Code (exclusive of interest, penalties, additional amounts, and additions to tax) for the taxable period over the amount of such tax paid on or before the last date prescribed for payment. Thus, any payments made after the last date prescribed for payment (for example, by way of an amended return) will not affect the existence of a threshold underpayment. In determining whether there is a threshold underpayment, different types of taxes (such as income tax and FICA tax) and amounts that relate to different taxable periods are not added together.

  (iii) When determined—(A) In general. The existence of a threshold underpayment of a tax and the amount of a large corporate underpayment are generally determined only when an assessment is made with respect to the taxable period. Thus, the amount of a deficiency or proposed deficiency set forth in a letter or notice pursuant to which the applicable date is determined (under paragraph (c) of this section) does not determine whether there is a large corporate underpayment.

  (B) Judicial determinations. Notwithstanding any prior assessment made with respect to a taxable period, the section 6621(c) rate does not apply if, after a federal court determines the taxpayer's liability for a period, the threshold underpayment for that taxable period does not exceed $100,000. See Example 3 in paragraph (d) of this section.

  (iv) Special rule. The section 6621(c) rate is not used to compute the interest charges that a taxpayer timely assesses against itself in return for using a method of tax accounting or reporting that defers the payment of tax, such as the interest charges relating to passive foreign investment companies under section 1291(c) and installment obligations of nondealers under section 453A(c). However, to the extent such charges are not paid on or before the last date prescribed for payment and therefore become part of an underpayment of a tax, the section 6621(c) rate will apply to such amounts for periods after the applicable date (as determined in paragraph (c) of this section).

  (3) C corporation defined. For purposes of section 6621(c)(3)(A) and this section, “C corporation” means, with respect to any taxable period, a corporation that is a C corporation during any part of the taxable period. Interest on a large corporate underpayment for a taxable period continues to be imposed at the section 6621(c) rate even if during or after the taxable period—

  (i) The taxpayer ceases to be a C corporation; or

  (ii) The underpayment becomes the liability of a successor or transferee that is not a C corporation.

  (4) Taxable period. For purposes of section 6621(c) and this section, the “taxable period” is the taxable year in the case of any tax imposed by subtitle A of the Internal Revenue Code. In the case of any other tax, the “taxable period” is the period to which the underpayment relates. For example, the taxable period for an underpayment of FICA taxes is the calendar quarter. If the underpayment does not relate to a particular period (for example, in the case of certain transactional excise taxes), the “taxable period” is the period covered by a return on which the tax is required to be shown.

  (5) Last date prescribed for payment. For purposes of this section, the “last date prescribed for payment” means the last date prescribed for payment as determined, without regard to any extension of time, under section 6601(b).

  (c) Applicable date—(1) In general. The section 6621(c) rate applies only to periods after the applicable date. Pursuant to the effective date of section 6621(c) and paragraph (e) of this section, however, the section 6621(c) rate will not apply prior to January 1, 1991, even if the applicable date is prior to December 31, 1990. A letter or notice relating to a particular type of tax creates an applicable date only for that type of tax. For example, a letter or notice with respect to FUTA tax will not create an applicable date with respect to income tax for the same taxable year.

  (2) When deficiency procedures apply. The applicable date, in the case of any underpayment of a tax to which the deficiency procedures of subchapter B of chapter 63 of the Internal Revenue Code apply, is the 30th day after the earlier of—

  (i) The date on which the Service sends the taxpayer the first letter of proposed deficiency that allows the taxpayer an opportunity for administrative review in the Service's Office of Appeals (commonly called a “30-day letter”); or

  (ii) The date on which the Service sends a deficiency notice under section 6212 of the Internal Revenue Code (commonly called a “90-day letter”).

  (3) When deficiency procedures do not apply. The applicable date, in the case of any underpayment of a tax to which the deficiency procedures do not apply, is the 30th day after the date on which the Service sends the first letter or notice that notifies the taxpayer of an assessment or proposed assessment of the tax. In the case of income taxes, for example, the deficiency procedures do not apply to amounts shown as due on the taxpayer's return if the taxpayer fails to remit the full amount on or before the last date prescribed for payment, and to amounts attributable to mathematical or clerical errors on a return (unless a request for abatement is filed by the taxpayer under section 6213(b)). Because no 30-day letter or 90-day letter is issued to the taxpayer in such cases, the applicable date is the 30th day after the date on which an assessment notice under section 6303 of the Internal Revenue Code is sent.

  (4) Partnership items. For purposes of section 6621(c) and this paragraph (c), 60-day letters and the notices described in sections 6223(a)(1) and 6223(a)(2) (relating to administrative proceedings at the partnership level) are not treated as letters of proposed deficiency that allow the taxpayer an opportunity for administrative review in the Service's Office of Appeals, deficiency notices under section 6212 of the Internal Revenue Code, or letters or notices that notify the taxpayer of an assessment or proposed assessment of the tax. Thus, in the absence of any other letter or notice described in paragraph (c)(2) or (c)(3) of this section that establishes an earlier applicable date, the applicable date in the case of any underpayment of a tax attributable, in whole or in part, to a partnership item (as defined in section 6231(a)(3)) is the 30th day after the date on which the Service sends the first letter or notice that notifies the taxpayer of an assessment of the tax.

  (5) Exception of payment of amount shown as due—(i) In general. A letter of notice will be disregarded for purposes of determining the applicable date if the taxpayer makes a payment equal to the amount shown as due in the letter or notice within 30 days from the date that the Service sends the letter or notice.

  (ii) Special transition rule. A letter or notice sent by the Service prior to January 1, 1991, will be disregarded by the Service for purposes of determining the applicable date if the taxpayer makes a payment on or before January 31, 1991, equal to the amount shown as due in the letter or notice plus a reasonable estimate of the interest payable on such amount computed by applying the section 6621(a)(2) rate. If the taxpayer has received two or more letters or notices with respect to the same tax for the same taxable period and pays the amount shown as due in the last letter or notice sent prior to December 19, 1990, (plus a reasonable estimate of the interest), all of the prior letters and notices with respect to the same tax for the same taxable period will be disregarded under this paragraph (c)(5)(ii). In the case of an assessment notice, the payment of the amount of interest shown as due on the last assessment notice sent to the taxpayer prior to December 19, 1990, will be treated as a payment of a reasonable estimate of the interest payable on the amount shown in that assessment notice or in any prior assessment notice sent with respect to the same tax for the same taxable period. The special transition rule in this paragraph (c)(5)(ii) applies even if the payment is not made within 30 days of the date on which the Service sent the letter or notice.

  (iii) Amount shown as due. For purposes of section 6621(c)(2)(B)(ii) and this paragraph (c)(5), the “amount shown as due” in any letter or notice means the total amount of tax, as well as any interest, penalties, additional amounts, and additions to tax that are set forth in the letter or notice. A deposit in the nature of a cash bond will not be considered a payment of the amount shown as due.

  (6) Exception for withdrawn letters and notices—(i) Letters of proposed deficiency. A letter of proposed deficiency will be disregarded for purposes of determining the applicable date if the letter of proposed deficiency is issued as a result of an administrative error either to the wrong taxpayer or for the wrong taxable period.

  (ii) Deficiency notices. A deficiency notice under section 6212 of the Internal Revenue Code will be disregarded for purposes of determining the applicable date if the deficiency notice is rescinded under section 6212(d).

  (iii) Assessment letters and notices. A letter or notice that notifies the taxpayer of an assessment or proposed assessment of tax will be disregarded for purposes of determining the applicable date if the full amount of tax assessed is subsequently abated.

  (d) Examples. The application of this section may be illustrated by the following examples.

  (e) Effective date. Section 6621(c) and this section are effective for determining interest for periods after December 31, 1990, regardless of the taxable period to which the underlying tax may relate and even if the applicable date is prior to December 31, 1990.

• Treas. Reg. §301.6621-3(a)In general. Show full text ▾ Collapse ▴

  In general. Section 6621 establishes the interest rate for purposes of computing the amount of interest that must be paid under section 6601, relating to interest on underpayments of tax. Section 6621(a)(2) provides that the underpayment rate is the sum of the Federal short-term rate (determined under section 6621(b)) plus 3 percentage points. That underpayment rate is referred to hereinafter as the “section 6621(a)(2) rate.” Section 6621(c) and this section, however, provide that the underpayment rate on any large corporate underpayment is the sum of the Federal short-term rate (determined under section 6621(b)) plus 5 percentage points. This higher underpayment rate is referred to hereinafter as the “section 6621(c) rate.” The section 6621(c) rate applies only for periods after the applicable date (as determined in paragraph (c) of this section).

• Treas. Reg. §301.6621-3(b)Large corporate underpayment—(1) Defined. Show full text ▾ Collapse ▴

  Large corporate underpayment—(1) Defined. For purposes of section 6621(c) and this section, “large corporate underpayment” means any underpayment of a tax by a C corporation for any taxable period if the amount of the threshold underpayment of the tax (as defined in paragraph (b)(2)(ii) of this section) for that taxable period exceeds $100,000.

  (2) Underpayment of a tax—(i) In general. As used in section 6621(c) and this section, “underpayment of a tax” means the excess of a tax imposed by the Internal Revenue Code over the amount of such tax paid on or before the last date prescribed for payment. Except as provided in paragraph (b)(2)(ii) of this section, “tax” for such purposes includes interest, penalties, additional amounts, and additions to tax. See sections 6601(e)(1), 6665(a), and 6671(a). Thus, the section 6621(c) rate generally applies to any interest, penalties, additional amounts, and additions to tax, as well as to the underlying tax with respect to which such amounts are imposed.

  (ii) Threshold underpayment of a tax. Solely for purposes of this section and not for any other purpose under section 6621(c) or elsewhere in the interpretation or administration of the federal tax laws, a “threshold underpayment of a tax” is the excess of a tax imposed by the Internal Revenue Code (exclusive of interest, penalties, additional amounts, and additions to tax) for the taxable period over the amount of such tax paid on or before the last date prescribed for payment. Thus, any payments made after the last date prescribed for payment (for example, by way of an amended return) will not affect the existence of a threshold underpayment. In determining whether there is a threshold underpayment, different types of taxes (such as income tax and FICA tax) and amounts that relate to different taxable periods are not added together.

  (iii) When determined—(A) In general. The existence of a threshold underpayment of a tax and the amount of a large corporate underpayment are generally determined only when an assessment is made with respect to the taxable period. Thus, the amount of a deficiency or proposed deficiency set forth in a letter or notice pursuant to which the applicable date is determined (under paragraph (c) of this section) does not determine whether there is a large corporate underpayment.

  (B) Judicial determinations. Notwithstanding any prior assessment made with respect to a taxable period, the section 6621(c) rate does not apply if, after a federal court determines the taxpayer's liability for a period, the threshold underpayment for that taxable period does not exceed $100,000. See Example 3 in paragraph (d) of this section.

  (iv) Special rule. The section 6621(c) rate is not used to compute the interest charges that a taxpayer timely assesses against itself in return for using a method of tax accounting or reporting that defers the payment of tax, such as the interest charges relating to passive foreign investment companies under section 1291(c) and installment obligations of nondealers under section 453A(c). However, to the extent such charges are not paid on or before the last date prescribed for payment and therefore become part of an underpayment of a tax, the section 6621(c) rate will apply to such amounts for periods after the applicable date (as determined in paragraph (c) of this section).

  (3) C corporation defined. For purposes of section 6621(c)(3)(A) and this section, “C corporation” means, with respect to any taxable period, a corporation that is a C corporation during any part of the taxable period. Interest on a large corporate underpayment for a taxable period continues to be imposed at the section 6621(c) rate even if during or after the taxable period—

• Treas. Reg. §301.6621-3(c)Applicable date—(1) In general. Show full text ▾ Collapse ▴

  Applicable date—(1) In general. The section 6621(c) rate applies only to periods after the applicable date. Pursuant to the effective date of section 6621(c) and paragraph (e) of this section, however, the section 6621(c) rate will not apply prior to January 1, 1991, even if the applicable date is prior to December 31, 1990. A letter or notice relating to a particular type of tax creates an applicable date only for that type of tax. For example, a letter or notice with respect to FUTA tax will not create an applicable date with respect to income tax for the same taxable year.

  (2) When deficiency procedures apply. The applicable date, in the case of any underpayment of a tax to which the deficiency procedures of subchapter B of chapter 63 of the Internal Revenue Code apply, is the 30th day after the earlier of—

• Treas. Reg. §301.6621-3(d)Examples. Show full text ▾ Collapse ▴

  Examples. The application of this section may be illustrated by the following examples.

• Treas. Reg. §301.6621-3(e)Effective date. Show full text ▾ Collapse ▴

  Effective date. Section 6621(c) and this section are effective for determining interest for periods after December 31, 1990, regardless of the taxable period to which the underlying tax may relate and even if the applicable date is prior to December 31, 1990.

• Treas. Reg. §301.6621-3(i)§301.6621-3(i) Show full text ▾ Collapse ▴

  The date on which the Service sends the taxpayer the first letter of proposed deficiency that allows the taxpayer an opportunity for administrative review in the Service's Office of Appeals (commonly called a “30-day letter”); or

  (ii) The date on which the Service sends a deficiency notice under section 6212 of the Internal Revenue Code (commonly called a “90-day letter”).

  (3) When deficiency procedures do not apply. The applicable date, in the case of any underpayment of a tax to which the deficiency procedures do not apply, is the 30th day after the date on which the Service sends the first letter or notice that notifies the taxpayer of an assessment or proposed assessment of the tax. In the case of income taxes, for example, the deficiency procedures do not apply to amounts shown as due on the taxpayer's return if the taxpayer fails to remit the full amount on or before the last date prescribed for payment, and to amounts attributable to mathematical or clerical errors on a return (unless a request for abatement is filed by the taxpayer under section 6213(b)). Because no 30-day letter or 90-day letter is issued to the taxpayer in such cases, the applicable date is the 30th day after the date on which an assessment notice under section 6303 of the Internal Revenue Code is sent.

  (4) Partnership items. For purposes of section 6621(c) and this paragraph (c), 60-day letters and the notices described in sections 6223(a)(1) and 6223(a)(2) (relating to administrative proceedings at the partnership level) are not treated as letters of proposed deficiency that allow the taxpayer an opportunity for administrative review in the Service's Office of Appeals, deficiency notices under section 6212 of the Internal Revenue Code, or letters or notices that notify the taxpayer of an assessment or proposed assessment of the tax. Thus, in the absence of any other letter or notice described in paragraph (c)(2) or (c)(3) of this section that establishes an earlier applicable date, the applicable date in the case of any underpayment of a tax attributable, in whole or in part, to a partnership item (as defined in section 6231(a)(3)) is the 30th day after the date on which the Service sends the first letter or notice that notifies the taxpayer of an assessment of the tax.

  (5) Exception of payment of amount shown as due—(i) In general. A letter of notice will be disregarded for purposes of determining the applicable date if the taxpayer makes a payment equal to the amount shown as due in the letter or notice within 30 days from the date that the Service sends the letter or notice.

  (ii) Special transition rule. A letter or notice sent by the Service prior to January 1, 1991, will be disregarded by the Service for purposes of determining the applicable date if the taxpayer makes a payment on or before January 31, 1991, equal to the amount shown as due in the letter or notice plus a reasonable estimate of the interest payable on such amount computed by applying the section 6621(a)(2) rate. If the taxpayer has received two or more letters or notices with respect to the same tax for the same taxable period and pays the amount shown as due in the last letter or notice sent prior to December 19, 1990, (plus a reasonable estimate of the interest), all of the prior letters and notices with respect to the same tax for the same taxable period will be disregarded under this paragraph (c)(5)(ii). In the case of an assessment notice, the payment of the amount of interest shown as due on the last assessment notice sent to the taxpayer prior to December 19, 1990, will be treated as a payment of a reasonable estimate of the interest payable on the amount shown in that assessment notice or in any prior assessment notice sent with respect to the same tax for the same taxable period. The special transition rule in this paragraph (c)(5)(ii) applies even if the payment is not made within 30 days of the date on which the Service sent the letter or notice.

  (iii) Amount shown as due. For purposes of section 6621(c)(2)(B)(ii) and this paragraph (c)(5), the “amount shown as due” in any letter or notice means the total amount of tax, as well as any interest, penalties, additional amounts, and additions to tax that are set forth in the letter or notice. A deposit in the nature of a cash bond will not be considered a payment of the amount shown as due.

  (6) Exception for withdrawn letters and notices—(i) Letters of proposed deficiency. A letter of proposed deficiency will be disregarded for purposes of determining the applicable date if the letter of proposed deficiency is issued as a result of an administrative error either to the wrong taxpayer or for the wrong taxable period.

  (ii) Deficiency notices. A deficiency notice under section 6212 of the Internal Revenue Code will be disregarded for purposes of determining the applicable date if the deficiency notice is rescinded under section 6212(d).

  (iii) Assessment letters and notices. A letter or notice that notifies the taxpayer of an assessment or proposed assessment of tax will be disregarded for purposes of determining the applicable date if the full amount of tax assessed is subsequently abated.