Oregon Revised Statutes Elections § 247.025

(1) A person's registration card must be received at an office or location described in ORS 247.012 not later than the time the office or location closes for business on the 21st day immediately preceding the election, but in no case later than midnight of the 21st day immediately preceding the election;

(2) A person's registration card must be postmarked not later than the 21st day immediately preceding the election and be addressed to an office of any county clerk, the Office of the Secretary of State, an office of the Department of Transportation or any designated voter registration agency as described in ORS 247.208; or

(3) A person's registration card must be delivered electronically as described in ORS 247.019 not later than 11:59 p.m. of the 21st day immediately preceding the election.