Oregon month-to-month leases are governed by Chapter 91 of Oregon Code: Tenancy: Property Rights and Transactions: Creation and Termination of Tenancies. There are no state laws in Oregon that govern how much a landlord may charge for a security deposit for a rental unit. The Oregon State Bar provides an informative page explaining the basics of security deposits for landlords and renters. However, the landlord and tenant should not be considered a substitute for legal advice. If landlords or tenants have questions about residential lease agreements, they should talk with a lawyer.
Under § 91.070, the notice period for lease termination is 30 days. It does not need to be 30 days notice from the beginning of the new month rental period. It can be at any point of the month, according to Oregon law.