If you hold complete ordination, you are permitted to serve in both Oregon and Washington — and California, Idaho, Arizona, too, as well as almost every other state. (Except Nevada, but that’s a different story.)
If your bridal couple has already obtained their marriage license, contact the issuing county clerk’s office and ask what their registration procedure is for Officiant’s.
Usually, you’ll simply have to fill in your name along with the church’s address and phone number on the marriage license. I’m a little hazy on this, but I think some counties will also have you include a copy of your ministerial credential or letter of good standing when returning the marriage license after the ceremony.
If anyone here has gone through the process in Oregon recently, please post.