You should send save-the-date cards to all of your intended guests when either of these circumstances fit your situation. Even friends and family members who you already know will attend should be sent a card.
Save the date cards can take the form of any message medium, and often do. They sometimes correspond in style to the wedding invitations, or they take the form of refrigerator magnets, brochures, postcards, booklets, or tri-fold letters. The medium is up to you, but the shortness of the message usually lends itself well to magnets or small cards.
Some companies offer digital save the date cards as well. What this means is you have the card to use on your computer and you could send them out to any email address that you have. Since almost every household has a computer and an email address, this would be a good way to save money on postage stamps.
Timing Is Everything – Wedding invitations are generally mailed out six to eight weeks prior to the event, but save the date cards should be sent out four to six months ahead of time. This way, guests will be able to shop around for transportation, schedule a convenient flight, reserve a hotel room, and make other necessary arrangements. Major events are exciting social gatherings that everyone will want to attend, both family and friends from near and far. Sending them out well enough in advance makes it far more likely that all of your guests will be able to attend.
There are many types of save-the-date. Although a save-the-date is traditionally a card, it can also take the form of magnets, bookmarks, or wedding stationery. Any type of save-the-date can be a meaningful keepsake of your wedding day. They also serve the purpose of giving your guests the first indication of what your wedding will be like and what to expect at the wedding reception.