26 U.S.C. § 6501
Section 6501 · Limitations on assessment and collection
Current version, with additions and removals from the July 31, 2015 version.
Except as otherwise provided in this section, the amount of any tax imposed by this title shall be assessed within 3 years after the return was filed (whether or not such return was filed on or after the date prescribed) or, if the tax is payable by stamp, at any time after such tax became due and before the expiration of 3 years after the date on which any part of such tax was paid, and no proceeding in court without assessment for the collection of such tax shall be begun after the expiration of such period. For purposes of this chapter, the term “return” means the return required to be filed by the taxpayer (and does not include a return of any person from whom the taxpayer has received an item of income, gain, loss, deduction, or credit).
Except as otherwise provided in this section, the amount of any tax imposed by this title shall be assessed within 3 years after the return was filed (whether or not such return was filed on or after the date prescribed) or, if the tax is payable by stamp, at any time after such tax became due and before the expiration of 3 years after the date on which any part of such tax was paid, and no proceeding in court without assessment for the collection of such tax shall be begun after the expiration of such period. For purposes of this chapter, the term “return” means the return required to be filed by the taxpayer (and does not include a return of any person from whom the taxpayer has received an item of income, gain, loss, deduction, or credit).
For purposes of this section, a return of tax imposed by this title, except tax imposed by chapter 3, 4, 21, or 24, filed before the last day prescribed by law or by regulations promulgated pursuant to law for the filing thereof, shall be considered as filed on such last day.
For purposes of this section, if a return of tax imposed by chapter 3, 4, 21, or 24 for any period ending with or within a calendar year is filed before April 15 of the succeeding calendar year, such return shall be considered filed on April 15 of such calendar year.
Notwithstanding the provisions of paragraph (2) of section 6020(b), the execution of a return by the Secretary pursuant to the authority conferred by such section shall not start the running of the period of limitations on assessment and collection.
For purposes of this section, the filing of a return for a specified period on which an entry has been made with respect to a tax imposed under a provision of subtitle D (including a return on which an entry has been made showing no liability for such tax for such period) shall constitute the filing of a return of all amounts of such tax which, if properly paid, would be required to be reported on such return for such period.
For purposes of this section, a return of tax imposed by this title, except tax imposed by chapter 3, 4, 21, or 24, filed before the last day prescribed by law or by regulations promulgated pursuant to law for the filing thereof, shall be considered as filed on such last day.
For purposes of this section, if a return of tax imposed by chapter 3, 4, 21, or 24 for any period ending with or within a calendar year is filed before April 15 of the succeeding calendar year, such return shall be considered filed on April 15 of such calendar year.
Notwithstanding the provisions of paragraph (2) of section 6020(b), the execution of a return by the Secretary pursuant to the authority conferred by such section shall not start the running of the period of limitations on assessment and collection.
For purposes of this section, the filing of a return for a specified period on which an entry has been made with respect to a tax imposed under a provision of subtitle D (including a return on which an entry has been made showing no liability for such tax for such period) shall constitute the filing of a return of all amounts of such tax which, if properly paid, would be required to be reported on such return for such period.
Except as otherwise provided in subsection (c), (e), or (f), in the case of any tax (other than the tax imposed by chapter 11 of subtitle B, relating to estate taxes) for which return is required in the case of a decedent, or by his estate during the period of administration, or by a corporation, the tax shall be assessed, and any proceeding in court without assessment for the collection of such tax shall be begun, within 18 months after written request therefor (filed after the return is made and filed in such manner and such form as may be prescribed by regulations of the Secretary) by the executor, administrator, or other fiduciary representing the estate of such decedent, or by the corporation, but not after the expiration of 3 years after the return was filed. This subsection shall not apply in the case of a corporation unless—
such written request notifies the Secretary that the corporation contemplates dissolution at or before the expiration of such 18-month period, (B) the dissolution is in good faith begun before the expiration of such 18-month period, and (C) the dissolution is completed;
such written request notifies the Secretary that a dissolution has in good faith been begun, and (B) the dissolution is completed; or
a dissolution has been completed at the time such written request is made.
Except as otherwise provided in subsection (c), (e), or (f), in the case of any tax (other than the tax imposed by chapter 11 of subtitle B, relating to estate taxes) for which return is required in the case of a decedent, or by his estate during the period of administration, or by a corporation, the tax shall be assessed, and any proceeding in court without assessment for the collection of such tax shall be begun, within 18 months after written request therefor (filed after the return is made and filed in such manner and such form as may be prescribed by regulations of the Secretary) by the executor, administrator, or other fiduciary representing the estate of such decedent, or by the corporation, but not after the expiration of 3 years after the return was filed. This subsection shall not apply in the case of a corporation unless—
such written request notifies the Secretary that the corporation contemplates dissolution at or before the expiration of such 18-month period, (B) the dissolution is in good faith begun before the expiration of such 18-month period, and (C) the dissolution is completed;
such written request notifies the Secretary that a dissolution has in good faith been begun, and (B) the dissolution is completed; or
a dissolution has been completed at the time such written request is made.
Except as otherwise provided in subsection (c)—
In the case of any tax imposed by subtitle A—
If the taxpayer omits from gross income an amount properly includible therein and—
such amount is in excess of 25 percent of the amount of gross income stated in the return, or
such amount—
is attributable to one or more assets with respect to which information is required to be reported under section 6038D (or would be so required if such section were applied without regard to the dollar threshold specified in subsection (a) thereof and without regard to any exceptions provided pursuant to subsection (h)(1) thereof), and
is in excess of $5,000,
the tax may be assessed, or a proceeding in court for collection of such tax may be begun without assessment, at any time within 6 years after the return was filed.
For purposes of subparagraph (A)—
In the case of a trade or business, the term “gross income” means the total of the amounts received or accrued from the sale of goods or services (if such amounts are required to be shown on the return) prior to diminution by the cost of such sales or services;
An understatement of gross income by reason of an overstatement of unrecovered cost or other basis is an omission from gross income; and
In determining the amount omitted from gross income (other than in the case of an overstatement of unrecovered cost or other basis), there shall not be taken into account any amount which is omitted from gross income stated in the return if such amount is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the nature and amount of such item.
If the taxpayer omits from gross income an amount properly includible therein under section 951(a), the tax may be assessed, or a proceeding in court for the collection of such tax may be done without assessing, at any time within 6 years after the return was filed.
In the case of a return of estate tax under chapter 11 or a return of gift tax under chapter 12, if the taxpayer omits from the gross estate or from the total amount of the gifts made during the period for which the return was filed items includible in such gross estate or such total gifts, as the case may be, as exceed in amount 25 percent of the gross estate stated in the return or the total amount of gifts stated in the return, the tax may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return was filed. In determining the items omitted from the gross estate or the total gifts, there shall not be taken into account any item which is omitted from the gross estate or from the total gifts stated in the return if such item is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the nature and amount of such item.
In the case of a return of a tax imposed under a provision of subtitle D, if the return omits an amount of such tax properly includible thereon which exceeds 25 percent of the amount of such tax reported thereon, the tax may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return is filed. In determining the amount of tax omitted on a return, there shall not be taken into account any amount of tax imposed by chapter 41, 42, 43, or 44 which is omitted from the return if the transaction giving rise to such tax is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the existence and nature of such item.
Except as otherwise provided in subsection (c)—
In the case of any tax imposed by subtitle A—
If the taxpayer omits from gross income an amount properly includible therein and—
such amount is in excess of 25 percent of the amount of gross income stated in the return, or
such amount—
is attributable to one or more assets with respect to which information is required to be reported under section 6038D (or would be so required if such section were applied without regard to the dollar threshold specified in subsection (a) thereof and without regard to any exceptions provided pursuant to subsection (h)(1) thereof), and
is in excess of $5,000,
the tax may be assessed, or a proceeding in court for collection of such tax may be begun without assessment, at any time within 6 years after the return was filed.
For purposes of subparagraph (A)—
In the case of a trade or business, the term “gross income” means the total of the amounts received or accrued from the sale of goods or services (if such amounts are required to be shown on the return) prior to diminution by the cost of such sales or services;
An understatement of gross income by reason of an overstatement of unrecovered cost or other basis is an omission from gross income; and
In determining the amount omitted from gross income (other than in the case of an overstatement of unrecovered cost or other basis), there shall not be taken into account any amount which is omitted from gross income stated in the return if such amount is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the nature and amount of such item.
If the taxpayer omits from gross income an amount properly includible therein under section 951(a), the tax may be assessed, or a proceeding in court for the collection of such tax may be done without assessing, at any time within 6 years after the return was filed.
In the case of a return of estate tax under chapter 11 or a return of gift tax under chapter 12, if the taxpayer omits from the gross estate or from the total amount of the gifts made during the period for which the return was filed items includible in such gross estate or such total gifts, as the case may be, as exceed in amount 25 percent of the gross estate stated in the return or the total amount of gifts stated in the return, the tax may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return was filed. In determining the items omitted from the gross estate or the total gifts, there shall not be taken into account any item which is omitted from the gross estate or from the total gifts stated in the return if such item is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the nature and amount of such item.
In the case of a return of a tax imposed under a provision of subtitle D, if the return omits an amount of such tax properly includible thereon which exceeds 25 percent of the amount of such tax reported thereon, the tax may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return is filed. In determining the amount of tax omitted on a return, there shall not be taken into account any amount of tax imposed by chapter 41, 42, 43, or 44 which is omitted from the return if the transaction giving rise to such tax is disclosed in the return, or in a statement attached to the return, in a manner adequate to apprise the Secretary of the existence and nature of such item.
If a corporation which is a personal holding company for any taxable year fails to file with its return under chapter 1 for such year a schedule setting forth—
the items of gross income and adjusted ordinary gross income, described in section 543, received by the corporation during such year, and
the names and addresses of the individuals who owned, within the meaning of section 544 (relating to rules for determining stock ownership), at any time during the last half of such year more than 50 percent in value of the outstanding capital stock of the corporation,
the personal holding company tax for such year may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return for such year was filed.
If a corporation which is a personal holding company for any taxable year fails to file with its return under chapter 1 for such year a schedule setting forth—
the items of gross income and adjusted ordinary gross income, described in section 543, received by the corporation during such year, and
the names and addresses of the individuals who owned, within the meaning of section 544 (relating to rules for determining stock ownership), at any time during the last half of such year more than 50 percent in value of the outstanding capital stock of the corporation,
the personal holding company tax for such year may be assessed, or a proceeding in court for the collection of such tax may be begun without assessment, at any time within 6 years after the return for such year was filed.
If a taxpayer determines in good faith that it is a trust or partnership and files a return as such under subtitle A, and if such taxpayer is thereafter held to be a corporation for the taxable year for which the return is filed, such return shall be deemed the return of the corporation for purposes of this section.
If a taxpayer determines in good faith that it is an exempt organization and files a return as such under section 6033, and if such taxpayer is thereafter held to be a taxable organization for the taxable year for which the return is filed, such return shall be deemed the return of the organization for purposes of this section.
If a corporation determines in good faith that it is a DISC (as defined in section 992(a)) and files a return as such under section 6011(c)(2) and if such corporation is thereafter held to be a corporation which is not a DISC for the taxable year for which the return is filed, such return shall be deemed the return of a corporation which is not a DISC for purposes of this section.
If a taxpayer determines in good faith that it is a trust or partnership and files a return as such under subtitle A, and if such taxpayer is thereafter held to be a corporation for the taxable year for which the return is filed, such return shall be deemed the return of the corporation for purposes of this section.
If a taxpayer determines in good faith that it is an exempt organization and files a return as such under section 6033, and if such taxpayer is thereafter held to be a taxable organization for the taxable year for which the return is filed, such return shall be deemed the return of the organization for purposes of this section.
If a corporation determines in good faith that it is a DISC (as defined in section 992(a)) and files a return as such under section 6011(c)(2) and if such corporation is thereafter held to be a corporation which is not a DISC for the taxable year for which the return is filed, such return shall be deemed the return of a corporation which is not a DISC for purposes of this section.
In the case of a deficiency attributable to the application to the taxpayer of a net operating loss carryback or a capital loss carryback (including deficiencies which may be assessed pursuant to the provisions of section 6213(b)(3)), such deficiency may be assessed at any time before the expiration of the period within which a deficiency for the taxable year of the net operating loss or net capital loss which results in such carryback may be assessed.
In the case of a deficiency attributable to the application to the taxpayer of a net operating loss carryback or a capital loss carryback (including deficiencies which may be assessed pursuant to the provisions of section 6213(b)(3)), such deficiency may be assessed at any time before the expiration of the period within which a deficiency for the taxable year of the net operating loss or net capital loss which results in such carryback may be assessed.
In the case of a deficiency attributable to the application to the taxpayer of a carryback under section 904(c) (relating to carryback and carryover of excess foreign taxes) or under section 907(f) (relating to carryback and carryover of disallowed foreign oil and gas taxes), such deficiency may be assessed at any time before the expiration of one year after the expiration of the period within which a deficiency may be assessed for the taxable year of the excess taxes described in section 904(c) or 907(f) which result in such carryback.
In the case of a deficiency attributable to the application to the taxpayer of a carryback under section 904(c) (relating to carryback and carryover of excess foreign taxes) or under section 907(f) (relating to carryback and carryover of disallowed foreign oil and gas taxes), such deficiency may be assessed at any time before the expiration of one year after the expiration of the period within which a deficiency may be assessed for the taxable year of the excess taxes described in section 904(c) or 907(f) which result in such carryback.
In the case of a deficiency attributable to the application to the taxpayer of a credit carryback (including deficiencies which may be assessed pursuant to the provisions of section 6213(b)(3)), such deficiency may be assessed at any time before the expiration of the period within which a deficiency for the taxable year of the unused credit which results in such carryback may be assessed, or with respect to any portion of a credit carryback from a taxable year attributable to a net operating loss carryback, capital loss carryback, or other credit carryback from a subsequent taxable year, at any time before the expiration of the period within which a deficiency for such subsequent taxable year may be assessed.
For purposes of this subsection, the term “credit carryback” has the meaning given such term by section 6511(d)(4)(C).
In the case of a deficiency attributable to the application to the taxpayer of a credit carryback (including deficiencies which may be assessed pursuant to the provisions of section 6213(b)(3)), such deficiency may be assessed at any time before the expiration of the period within which a deficiency for the taxable year of the unused credit which results in such carryback may be assessed, or with respect to any portion of a credit carryback from a taxable year attributable to a net operating loss carryback, capital loss carryback, or other credit carryback from a subsequent taxable year, at any time before the expiration of the period within which a deficiency for such subsequent taxable year may be assessed.
For purposes of this subsection, the term “credit carryback” has the meaning given such term by section 6511(d)(4)(C).
In a case where an amount has been applied, credited, or refunded under section 6411 (relating to tentative carryback and refund adjustments) by reason of a net operating loss carryback, a capital loss carryback, or a credit carryback (as defined in section 6511(d)(4)(C)) to a prior taxable year, the period described in subsection (a) of this section for assessing a deficiency for such prior taxable year shall be extended to include the period described in subsection (h) or (j), whichever is applicable; except that the amount which may be assessed solely by reason of this subsection shall not exceed the amount so applied, credited, or refunded under section 6411, reduced by any amount which may be assessed solely by reason of subsection (h) or (j), as the case may be.
In a case where an amount has been applied, credited, or refunded under section 6411 (relating to tentative carryback and refund adjustments) by reason of a net operating loss carryback, a capital loss carryback, or a credit carryback (as defined in section 6511(d)(4)(C)) to a prior taxable year, the period described in subsection (a) of this section for assessing a deficiency for such prior taxable year shall be extended to include the period described in subsection (h) or (j), whichever is applicable; except that the amount which may be assessed solely by reason of this subsection shall not exceed the amount so applied, credited, or refunded under section 6411, reduced by any amount which may be assessed solely by reason of subsection (h) or (j), as the case may be.
1 So in original. Probably should be followed by “section”.
In the case of a deficiency attributable to an error with respect to the determination under section 7701(a)(52) for any taxable year, such deficiency may be assessed at any time within 6 years after the return for such year was filed.
For period of limitations for assessment and collection in the case of a joint income return filed after separate returns have been filed, see section 6013(b)(3) and (4).