A save-the-date and a wedding invitation each serve a different purpose for your guest list. Here's the biggest difference between the two: Save-the-dates are sent early in the wedding planning process to ask your guests to hold the date in their calendars for your wedding while the formal invitations are been finalized. A wedding invitation is a piece that contains all the necessary details to invite a guest to attend your wedding. In other words, think of a save-the-date as a heads up that they're invited, while the actual invitation formally invites them with all the details.
