I feel like much of my job is matching a package to each bride’s level of budget and etiquette.  Those are two different variables, however.  I have many brides who are comfortable spending $10/card and many (most!) who want to spend $1/card; likewise many want to be as formal as the Queen of England, and many want to be as casual as Lady Gaga.  In the end my job here is to allow anyone to look however they like, which includes teaching them how to cut corners.

So in an effort to save money, many brides try to skip having an RSVP card.  That can be okay.  At my own wedding, I didn’t have an RSVP card…

The real question here is “where is your break-even point?”  That’s the only math.  You’re not really going to call everyone to find out if they’re coming, so it all boils down to:

• Are you having an event where you are paying per person? (i.e. a dinner?)
• Are you having an event with limited space?
• How much are you paying per person?
• Will you or your mother not be able to relax unless you/she knows precisely who will be there?
• Is your family political/dysfunctional enough that people veering off the seating chart will be a big deal?

Then simply do the math.  If you’re paying $25/person, then being two people more accurate will probably pay off the expense of RSVP cards.  Maybe it’ll take 3, or 4, people, but if you’re having any kind of per-person cost spending money on an RSVP card will save you a lot of money very quickly.