But you should definitely send RSVP cards to anyone over the age of 40, and give them the option on the RSVP card to reply online if they choose to.

Etiquette is changing because times are changing.
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Common Sense

From Miss Manners herself: "Response cards were never correct. They are a desperate, and not particularly successful, way to make up for the extreme rudeness of people who think it too much trouble to inform their hosts whether or not they will attend an occasion to which they have been kindly bidden. Wedding invitations are properly answered on your very own paper, with your very own hand. Following the form of the invitation, they say either that "Mr. and Mrs. Phiffle accept with pleasure" or "regret exceedingly that they are unable to accept" the kind invitation of their hosts."

That being said, people just are too rude to respond anyway, so to compromise I included a response card that had the same graphic from our invite with a short one line text that said, "The favor of a reply is requested by May 1." The card opened to an empty field where guests could write their response. On the back, I included my address, email, and phone number. I don’t care how people respond if they don’t know the correct way, as long as I know if they are coming. I included the self-addressed envelope but did not bother to waste stamps that will probably not get sent anyway.

Good Luck!
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May I suggest that you use telephone than the internet to handle your RSVPs? You aren’t expected to take and make all those calls yourself. In the old days (1900s) our bridesmaids and groomsmen handled this.

The "real time" communication of telephone will let your helpers prevent awkwardness when prospective guests don’t quite understand who is invited and who is not. Your helpers will be prepared to say things like "There is some misunderstanding. The invitation is for Homer and Marge. Bart, Lisa, and Maggie are not on the guest list. Do you need a few days to arrange for a sitter? May I give you call on Thursday?" and "I’m sure the couple would love to meet your new boyfriend, but the wedding is only for people they know and care about. Please do come, as we need more single ladies to dance with all the single men." And so on.

Further, during this phone conversation many people will ask "Where are they registered? What sort of gift would they like?" You do want an opportunity to share this infomation, don’t you?
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Besides, the mailed RSVP is the proper way to go. Follow up with phone calls anyone who doesnt send it back. Might be a pain, but theres no way around it. Besides, youll get a *more* accurate count that way.
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The polite thing is to let your friends reply using the method most convenient for them, and put a phone number, website or email address on the invitation under the R.s.v.p. line. Those of us who are still traditional will write you a polite hand-written note along the lines of "Miss Aspasia Phipps/accepts with pleasure the kind invitation of/&tc." Those of us who are a little more modern will phone, and the legitimate innovators will text, email, or visit your website.

Please don’t commit the solecism of trying to force your guests into a mold that suits your convenience.
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I understand your frustration. I’ve been there myself. It’s still good etiquette to send the pre-stamped, pre-addressed RSVP cards or postcards for the convenience of your guests for medium to large formal and semiformal weddings. If you see how difficult it is to get responses with a convenient pre-stamped , pre-addressed card, don’t expect that they will write you a note of acceptance with their own stationary themselves. Most people lead much busier lives today than the high society people of yesterday where letter writing and penmanship was an art.

You can also include the website RSVP info. to give them an alternative. Add your phone number as well if you like, but then you’ll have to field phone calls when you might be busy with your planning. You want to make this convienient for you as well.

If you’re having a casual wedding, a website RSVP info. and/or phone number should suffice. There’s more flexibility with small casual weddings.

For all of these options, if you don’t receive RSVPS by the deadline, split up your "nonresponses" with your fiance, bridesmaids, etc. and call to verify attendance. It will be easier for you that way. Your "nonresponse" list will be a much shorter call list than a FULL invite list. You and your wedding party don’t want to be calling, leaving messages, and recalling EVERYBODY you’re inviting with wedding planning and other things to do.
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