Outer Envelope: Formal

Your guests’ names written out fully with no nicknames or initials. Married couple will be addressed as “Mr. and Mrs.”—unless they have different professional titles—and all states and street abbreviations will be spelled out. House numbers below 20 will also spelled out:

Mr. and Mrs. Jerald Kirkpatrick Nineteen Village Drive Chickasha, Oklahoma 73018

But wait, what if Mr. Kirkpatrick is actually Dr. Kirkpatrick? Then the first line is now:

Doctor and Mrs. Jerald Kirkpatrick

And if Mrs. Kirkpatrick is the doctor?

Doctor Brenda Kirkpatrick and Mr. Jerald Kirkpatrick

What if they’re both doctors? (Who knew your guests were so fancy?)

The Doctors Kirkpatrick

What if they have different professional titles? Then it’s ladies first:

Captain Brenda Kirkpatrick, U.S. Army and The Honorable Jerald Kirkpatrick

And what if Brenda just kept her maiden name? Then again, ladies first:

Mrs. Brenda Jones and Mr. Jerald Kirkpatrick

What if Brenda and Jerald live together, but aren’t married?

Ms. Brenda Jones Mr. Jerald Kirkpatrick

What about Brenda and Jerald’s kids? Even if you want to invite them, their names do not appear on the outer envelope. Why? Because Emily Post and Martha Stewart said so.

Outer Envelope: Informal

Does omitting the wives’ first name seem a bit old fashioned? Informal addressing uses the woman’s first name and doesn’t bother with writing out house numbers under 20:

Brenda and Jerald Kirkpatrick 19 Village Drive Chickasha, Oklahoma 73018

Inner Envelopes: Formal

Barring all the confusing title issues covered above, it will read:

Mr. and Mrs. Kirkpatrick

Still want to invite their children? Then a boy under the age of 13 is called “Master,” a boy over the age of 13 is called “Mr.” and a girl under the age of 18 is called “Miss”:

Mr. and Mrs. Kirkpatrick Mr. Andrew Kirkpatrick, Miss Courtney Kirkpatrick, Master Edward Kirkpatrick

Inner Envelopes: Informal

Everyone is addressed by their first name or nickname:

Aunt Brenda and Uncle Jerry Andrew, Courtney, Edward

Inviting a single person, but giving them the option of a guest?

Brenda Jones and Guest