701—300.2(422) Statute of limitations.
	300.2(1) Periods of audit.
	a. 	The department has three years after a return has been filed or three years after the return became due, including any extensions of time for filing, whichever time is the later, to determine whether any additional tax other than that shown on the return is due and owing. This three-year statute of limitations does not apply in the instances specified in paragraphs “b,” “c,” “d,” “e,” “f” and “g.”
	b. 	If a taxpayer fails to include in the taxpayer’s return items of gross income as defined in the Internal Revenue Code as amended, as will under that Code extend the statute of limitations for federal tax purposes to six years, the correct amount of tax due may be determined by the department within six years from the time the return is filed, or within six years after the return became due, including any extensions of time for filing, whichever time is the later.
	c. 	If a taxpayer files a false or fraudulent return with intent to evade tax, the correct amount of tax due may be determined by the department at any time after the return has been filed.
	d. 	If a taxpayer fails to file a return, the periods of limitations so specified in Iowa Code section 422.25 do not begin to run until the return is filed with the department.
	e. 	While the burden of proof of additional tax owing under the six-year period or the unlimited period is upon the department, a prima facie case of omission of income, or of making a false or fraudulent return, shall be made upon a showing of a federal audit of the same income, a determination by federal authorities that the taxpayer omitted items of gross income or made a false or fraudulent return, and the payment by the taxpayer of the amount claimed by the federal government to be the correct tax or the admission by the taxpayer to the federal government of liability for that amount.
	f. 	In addition to the periods of limitation set forth in paragraph “a,” “b,” “c,” “d,” or “e,” the department has six months after notification by the taxpayer of the final disposition of any matter between the taxpayer and the Internal Revenue Service with respect to any particular tax year to make an examination and determination. Final disposition of any matter between the taxpayer and the Internal Revenue Service triggers the extension of the statute of limitations for the department to make an examination and determination, and the extension runs until six months after the department receives notification and a copy of the federal document showing the final disposition or final federal adjustments from the taxpayer. Van Dyke v.	Iowa Department of Revenue and Finance, 547 N.W.2d 1. This examination and determination is limited to those matters between the taxpayer and the Internal Revenue Service which affect Iowa taxable income. Kelly-Springfield Tire Co.	v.	Iowa State Board of Tax Review, 414 N.W.2d 113 (Iowa 1987). The notification shall be in writing in any form sufficient to inform the department of final disposition, and attached to the notification shall be a photo reproduction or carbon copy of the federal document which shows the final disposition and any schedules necessary to explain the federal adjustments. The notification and copy of the federal document shall be mailed, under separate cover, to the Examination Section, Compliance Division, P.O. Box 10456, Des Moines, Iowa 50306. Any notification and copy of the federal document which is included in, made a part of, or mailed with a current year Iowa individual income tax return will not be considered as proper notification for the purposes of beginning the running of the six-month period.
	g. 	In lieu of the period of limitation for any prior year for which an overpayment of tax or an elimination or reduction of an underpayment of tax due for that prior year results from the carryback to such prior year of a net operating loss or net capital loss, the period shall be the period of limitation for the taxable year of the net operating loss or net capital loss which results in such carryback.
	300.2(2) Waiver of statute of limitations. When the taxpayer and the department enter into an agreement to extend the period of limitation, interest continues to accrue on any deficiency or overpayment during the period of the waiver. The taxpayer may claim a refund during the period of the waiver.
	300.2(3) Amended returns filed within 60 days of the expiration of the statute of limitations for assessment. If a taxpayer files an amended return on or after April 1, 1995, within 60 days prior to the expiration of the statute of limitations for assessment, the department has 60 days from the date the amended return is received to issue an assessment for applicable tax, interest, or penalty.
This rule is intended to implement Iowa Code section 422.25.
[Editorial change: IAC Supplement 11/2/22]