ORS 319.375: Limitation on credit for or refund of overpayment and on assessment of additional tax.

(1) Except as otherwise provided in ORS 319.010 to 319.420, any credit for erroneous overpayment of tax made by a dealer taken on a subsequent return or any claim for refund of tax erroneously overpaid filed by a dealer must be so taken or filed within three years after the date on which the overpayment was made to the state.

      (2) Except in the case of a fraudulent report or neglect to make a report, every notice of additional tax proposed to be assessed under ORS 319.010 to 319.420 shall be served on dealers within three years from the date upon which such additional taxes become due.