The single “M” on a wedding RSVP card often confuses guests who are unsure what to write. Some might think it stands for “Maybe” or has something to do with meal preferences, but its meaning is much simpler. The letter traditionally serves as the beginning of a courtesy title, such as Mr., Mrs., Ms., or Miss, followed by the guest’s name.

This custom comes from older wedding etiquette, when formal titles were commonly used on invitations and other written correspondence. The “M” was included as a prompt for guests to complete the line with their preferred title and name. Although this tradition was once widely understood, changing social habits have made it less familiar.

Modern wedding etiquette is much more flexible, and guests do not necessarily need to follow these traditional rules. They can use the title they prefer or simply write their names, depending on the invitation’s format. The purpose of an RSVP card is to collect clear responses to help the couple organize seating, meals, and other arrangements.

Despite changes in how people celebrate weddings, the traditional “M” continues to appear on many invitation cards. Understanding its origin turns an awkward guessing game into a simple piece of history, and guests do not need to worry about getting every detail perfect as long as they indicate attendance and return the card before the deadline.