Oregon Revised Statutes Revenue and Taxation § 320.320

If the amount paid by the transient lodging tax collector to the Department of Revenue under ORS 320.315 exceeds the amount of tax payable, the department shall refund the amount of the excess with interest thereon at the rate established under ORS 305.220 for each month or fraction of a month from the date of payment of the excess until the date of the refund. A refund may not be made to a transient lodging tax collector that fails to claim the refund within two years after the due date for filing the return to which the claim for refund relates.