Welcome to Washington State Courts. I the undersigned do solemnly swear or affirm, that the information on this form is true: that I am eighteen years of age or older.Make sure you use your full legal name, including your middle name if applicable. Please read the instructions carefully. 1. Get a free affidavit of marriage sample with 360 Legal Forms. Get customized and printable legal forms for businesses and individuals. Free printable affidavit forms available at . Marriage license forms and affidavits are available in our office lobby. If you have questions, call for assistance. Both parties must sign the application in front of a Notary Public. 2.