If we've said it once, we've said it a thousand times: RSVPs still matter! Very much so. While no one is obligated to accept an invitation or to explain the reasons for not accepting, you do have an obligation to let your host whether or not you will attend. Unfortunately for hosts, no one will come running to your door and demand that you finally reply to that invitation that has been sitting on your coffee table for three weeks. We live in a more casual society today, but a host planning an event still needs to know how many people to expect. And more than that, just as someone is being kind when inviting you to an event, you should be just as kind to reply to their invitation.
So, the next time an invitation lands in your mailbox or inbox, be sure to do the following:
If you received your invitation by email, then an emailed response is acceptable. If the invitation is to a wedding and includes an enclosed card, then send your response by mail. You can judge the required response by the formality of the invitation itself.
Generally it is best to reply as soon as possible. For written invitations responses are made within several days of receiving the invitation. For in-person or phoned invitations, you may provide your response when asked or await until you have checked your schedule. Simply let the person know that you will call as soon as possible.
There is no need to go into great detail if you must decline the invitation. Write a simple and polite note of regret. If you feel like you must offer an explanation, be sure it is brief.
If you would like to accept an invitation to an informal or casual event but have a tentative conflict, contact the host or hostess to explain the problem. If the event is formal, however, your delay might inconvenience the host, so it's best to decline the invitation.
If the invitation does not specifically request that you RSVP, then a response is not necessary. However, it is always polite to notify the host when you cannot attend. A phone call will usually suffice, though you might send a personal note or an email.