Wedding invitations were once delivered by hand. If you were a bride back in those days, your footman delivered your invitations to your guests' homes. Their servants received the invitations and removed them from their mailing envelope, an envelope much too pedestrian for your guests to handle themselves. The servants, then, presented the invitation to your guests in its pristine inside envelope. Because the invitations were already at their destination, the inside envelopes had only the names of your guests written on them. The address was no longer needed. They just had to be directed to the appropriate members of the household.
Wedding invitations are still sent in two envelopes. The outside envelope is the mailing envelope. No abbreviations are used. "Rural Route" and "Post Office Box" are always written out.
Your guests' names and addresses are written on its face. The copy may be centered or staggered. Staggered copy was much more popular years ago before there was such a thing as zip codes and before it was necessary to include the state on invitations sent in-state. Now, the addition of states and zip codes has, in most cases, made the last line too long to be staggered.
Your guests' names are repeated on the inside envelope. This time, however, only their titles and surnames are used. If children under the age of eighteen are invited, their first names would appear on the line beneath their parents' names.
If you have nice handwriting, you may address the envelopes yourself, if not, you may hire a calligrapher instead. Calligraphy is a centuries-old art that was practiced in monasteries by monks who copied bibles and other important documents by hand. Copying books and documents by hand eventually all but ceased as printing and engraving replaced the scribe. Indeed, many of the lettering styles available in engraving can be traced back to old calligraphic styles. Calligraphy is still practiced today and gives your wedding envelopes a charming Old World look. Wedding envelopes are addressed using the same etiquette that is used on wedding invitations. Because they are seen only by their recipients, less traditional etiquette is occasionally used, especially with women's names and titles. "Ms.," for example, may be used when addressing envelopes even though it is not properly used on invitations.
Wedding envelopes are addressed to match the invitations.