answer:This is, at least what emilypost.com says about the business of addressing correspondence, including couples, including the order of names, where it states the following: NOTE: Traditionally, a man’s name preceded a woman’s on an envelope address, and his first and surname were not separated (Jane and John Kelly). Nowadays, the order of the names—whether his name or hers comes first—does not matter and either way is acceptable. The exception is when one member of the couple ‘outranks’ the other—the one with the higher rank is always listed first.