2011 ORS § 90.155¹
Service or delivery of written notice

(1) Except as provided in ORS 90.300 (Security deposits), 90.425 (Disposition of personal property abandoned by tenant) and 90.675 (Disposition of manufactured dwelling or floating home left in facility), where this chapter requires written notice, service or delivery of that written notice shall be executed by one or more of the following methods:

(a) Personal delivery to the landlord or tenant;

(b) First class mail to the landlord or tenant; or

(c) If a written rental agreement so provides, both first class mail and attachment to a designated location. In order for a written rental agreement to provide for mail and attachment service of written notices from the landlord to the tenant, the agreement must also provide for such service of written notices from the tenant to the landlord. Mail and attachment service of written notices shall be executed as follows:

(A) For written notices from the landlord to the tenant, the first class mail notice copy shall be addressed to the tenant at the premises and the second notice copy shall be attached in a secure manner to the main entrance to that portion of the premises of which the tenant has possession; and

(B) For written notices from the tenant to the landlord, the first class mail notice copy shall be addressed to the landlord at an address as designated in the written rental agreement and the second notice copy shall be attached in a secure manner to the landlords designated location, which shall be described with particularity in the written rental agreement, reasonably located in relation to the tenant and available at all hours.

(2) If a notice is served by mail, the minimum period for compliance or termination of tenancy, as appropriate, shall be extended by three days, and the notice shall include the extension in the period provided.

(3) A landlord or tenant may utilize alternative methods of notifying the other so long as the alternative method is in addition to one of the service methods described in subsection (1) of this section.

(4) Notwithstanding ORS 90.510 (Statement of policy) (4), after 30 days written notice, a landlord may unilaterally amend a rental agreement for a manufactured dwelling or floating home that is subject to ORS 90.505 (Definition for ORS 90.505 to 90.840) to 90.840 (Park purchase funds, loans) to provide for service or delivery of written notices by mail and attachment service as provided by subsection (1)(c) of this section. [Formerly 90.910; 1997 c.577 §6; 2001 c.596 §29a]