So what's the scientific forumla for calculating how many non-responders will turn up??

[smogwod]

Is it number of non-responders multiplied by birthday child's age divided by number of invites, minus glasses of wine consumed pre-party?!

I always account for one non responder replying because sometimes (as we had recently) there can be a genuine misunderstanding.

But other than that, I don't allow for them at all. If they don't respond, I don't count them. I think you'd have to be a pretty cheeky person to not reply and then turn up anyway.

For DD2's party earlier this year we had 1 non-responder who then turned up on the day (v. fortunately as it was her best friend from nursery and dd would have been devastated if she weren't there).

But I'm hoping that the rule isn't that 100% will turn up as that'll be an extra 6 for DD1's party on Saturday!

IME half of non responders will turn up, and 2 or 3 who said they will be coming, will drop out on the day due to illness / parent forgot already committed to something else etc etc.

This year I sent out invitations 3 weeks in advance with an RSVP by date of a week before party. I also left out vital information about the location so that people had to RSVP in time.

I had a phone call whilst driving to the party replying to say they were coming but didn't know where to go

Your guess is as good as anyones

Wow, that is just beyond cheeky! Good idea re. the location, might try that next time...

I'd forgotten about the likely last minute no-shows though so hopefully it'll all even out. I've got 16 accepted and 6 non-responders so if I cater for 20 I should have more than enough, fingers crossed.

I'd say 20 should be reasonably safe, OP.