I have no idea on this one. I feel like the postal service there should deliver it if you put Mr (they'll be able to figure it out) so that's probably what I would do. But that's just becuase my Spanish is so bad, I wouldn't even want to pretend to speak it on an invitation envelope
For FI's family in Germany, we addressed everyone as Herr or Frau as appropriate in their native language. Just make sure if you do this that you spell it/use it properly.
Sr. or Mr. are fine. I tred to use the correct title for my international guests (Sr./Sra./Herr), unless they were expats, then they got the American English title.
Re: Next Invite Address Question
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