Oregon Revised Statutes Revenue and Taxation § 323.185

(1) Amounts owing for stamps purchased on the deferred-payment basis for a calendar month shall be due and payable on or before the 20th day of the next calendar month. Payments shall be made by a remittance payable to the Department of Revenue.

(2) The department for good cause may extend the time for paying any amount owing for stamps purchased on the deferred-payment basis. The extension may not exceed five days. The extension may not be granted unless a request for the extension is filed with the department within or prior to the period for which the extension may be granted.