Oregon Revised Statutes Property Rights and Transactions § 90.140

(1) A landlord may require or accept the following types of payments:

(2) A tenant who requests a writing that evidences the tenant's payment is entitled to receive that writing from the landlord as a condition for making the payment.  The writing may be a receipt, statement of the tenant's account or other acknowledgment of the tenant's payment.  The writing must include the amount paid, the date of payment and information identifying the landlord or the rental property.  If the tenant makes the payment by mail, deposit or a method other than in person and requests the writing, the landlord shall within a reasonable time provide the tenant with the writing in a manner consistent with ORS 90.150.