Long-standing tradition states that invitations should be addressed to couples using their titles, the first name of the male partner, and their last name (Mr. and Mrs. John Smith).
How to Address Wedding Invitations: Traditional Etiquette
If you are inviting a couple, either name can appear first. Tradition states that the male name comes first; however, either way, it is suitable by modern standards.
How to Address a Wedding Invitation to a Married Couple