§ 5882. Time limitation on notices of deficiency and assessment of penalty and interest
(a) The Commissioner may notify a taxpayer of a deficiency with respect to the payment of any tax liability, or assess a penalty or interest with respect thereto, in accordance with section 3202 of this title, at any time within three years after the date that tax liability was originally required to be paid under this chapter.
(b) Notwithstanding subsection (a) of this section:
(1) If the taxpayer fails to file a proper return with respect to any tax liability at the time prescribed for its filing, the notification or assessment may be made at any time before the end of three years after the taxpayer files such a return.
(2) If the deficiency is caused by reason of fraud or the willful intent of the taxpayer to defeat or evade this chapter, the notification or assessment may be made at any time.
(3) If the notice of deficiency or assessment is founded upon an assertion or determination by the United States that the taxable income, or income tax liability, of the taxpayer under the laws of the United States is greater than the amount of the taxable income or income tax liability reported on any return of the taxpayer filed under the laws of the United States, the notification or assessment under section 3203 of this title may be made within the time prescribed under subsection (a) of this section, or at any time before the expiration of six months after the date the Commissioner is notified, in writing, by the taxpayer or by the United States of the federal assertion or determination, whichever period is the later to expire.
(4) If the taxpayer and Commissioner agree, the notification or assessment may be made at any time before the date so agreed upon.
(5) If a person withholds tax under subchapter 4 of this chapter but under-reports the tax withheld by 20 percent or more, the notification or assessment may be made at any time before the expiration of six years from the date of the filing of such return.
(6) If the notice or deficiency is based upon a refund that was paid in error, the notification or assessment under section 3203 of this title may be made within the time prescribed under subsection (a) of this section or at any time before the expiration of one year after the date the refund was paid, whichever period is the later to expire. (Added 1966, No. 61 (Sp. Sess.), § 1, eff. Jan. 1, 1966; amended 1989, No. 119, § 13, eff. June 22, 1989; 2007, No. 190 (Adj. Sess.), § 21, eff. June 6, 2008.)