How long must I know my fiance before we can apply for a K-1 visa? The way the regulation reads is this. You must have physically met with your fiance within two year period. I think it would be a good idea to have had a relationship for six months or more online before you meet in person. Remember there will be an interview so this will look much better to the person giving the interview than if you would only know each other for a month. You may get more information here
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