Hm, I thought I had this worked out, but FI and I just got an invite to my cousin's wedding that was addressed as:
Mr. FI
Ms. Irishcurls
Address
But they have never met my FI, so it got me thinking....to our unmarried guests that we're including guests that we don't know well/never met, does the man always go first? Regardless of relationship to the B&G?
Re: Unmarried couple, does name order matter?
This is wrong. Female ALWAYS goes first for unmarried couples.
Mrs. Blog | Ms. Bio


Similarly, if the couple is married and the woman keeps her maiden name, her name is listed first.
In general, I'd write the lady's name first.
Mr. John Smith
Ms. Jane Doe
because I personally thought it would be really weird to put the name of a woman I didn't know above the name of the cousin I was actually inviting. Of course, for my female friends, I put their name first.