Q&A: Invitation Wording: How to Address Inner Envelopes?
Q: Recently I received two wedding invitations. The inside envelope was addressed differently on each one. One to Mr. and Mrs. and one to John and Jane Smith. Now that I'm sending out wedding invitations, I'd like to know which is correct. Or are both acceptable?
A: The correct way to address inside envelopes is to just use titles: Mr. and Mrs., Ms., or Miss, whichever is appropriate. First names only go on the outer envelope (Mr. and Mrs. John Smith, or Mr. John Smith and Mrs. Jane Smith). Having first names on the inner envelope doesn't confuse the issue at all, so it wouldn't be an egregious faux pas. But titles only is the traditional way to do it.