Follow some basic rules for addressing your invitations:
You only need 1 invitation per household.
If you wish to control who is invited, this is where you do it.
Addressing lets people know who's invited, so make sure there are no misunderstandings.
When you address a letter to:
The Smith Family or The Smith Household - Everyone in that house, including children are invited.
Mr. & Mrs. Smith or Mr. John Smith & Mrs. Jane Smith - Only those listed are invited.
Mr. John Smith - No guest is invited
Mr. John Smith and Guest - Tells them a guest is invited.
Couples who live together receive a single invitation. Address it the same way you’d address the invitation of a married couple with different last names.
Address an invitation to a married couple, both doctors like this: The Doctors Smith. It’s that simple. If they are married, but have different last names, list both names in alphabetical order (on separate lines): Dr. Benton, and on the next line, Dr. Smith
Married couple, one a doctor: the spouse with the professional title is listed first. Dr. Kate Lawler and Mr. Brian Lawler or Dr. and Mr. Lawler
A widow is traditionally addressed as “Mrs. John Smith”, but if you feel the guest may not want to be addressed that way, ask how she prefers to be addressed
A divorced woman who has kept her married name should be addressed as Ms. Jane Alden
Same sex couple who have exchanged vows: Ms. Jane Allen Ms. Tara Allen. List Jane first, as “J” comes before “T” alphabetically. If you do not want to use titles or put the two on separate lines, use Jane and Tara Allen