Do private schools always over offer?

The head master at Dulwich said he is going to make 100 offers for 70 places. That’s not that much at all, really worrying.

Waitlist. Sheesh. Hate typing on the phone.

Schools that rescind offers after a short time period will have pre-notified candidates of this system. OP, I wouldn't worry. The application stats you outline are not particularly onerous. You have to factor in that a % will be candidates that are way under the mark. Once they have been taken out if the equation you looks to have probably a 2:1 ratio of applicants to places. That's pretty safe. As others have mentioned, people apply to 3,4,5 or more schools. The actual numbers that decline offers depends on the school. A very high ranking school will not over offer as many places as they know most offers will bring an acceptance. So they will only over offer a few places. Schools that are known as being back up schools will know that they will have a lot of offers declined so they over offer a lot of places. The schools themselves know where they sit in the desirability spectrum. They dint always get it right as you get funny years where people accept and decline against the curve but it's something the schools each have a system for calculating. On those peculiar years, schools end up putting in an extra class or having spaces left depending on which way it went. Most of not all schools run a what list system to try to manage this whole tricky numbers business. But I wouldn't worry too much about your ratios as it sounds like you have applied to decent but not incredibly hard to get into schools and the application numbers are pretty safe.

The 2 that had ‘exploding offers’ last year were Channing and CLSG (City girls). Both schools have confirmed that they are following the same system this year as it ‘works for them’. I don’t think they are particularly concerned about the negative publicity. Awful system I think, mainly because their offers come out before the state allocations.

This is certainly the case with the SW London indes.

Where were there exploding offers previously?

Ime yes, and occasionally schools get caught out by the number of acceptances, having to put on extra classes. This may then impact on capacity to accept pupils at 13+. It will be interesting to see if those schools previously highlighted for "exploding offers" repeat that strategy this year, despite negative publicity.

Just accept immediately! There have been many instances of offers being withdrawn to those who didn’t accept within 12 hours or whatever!

Certain schools only offer to those that will do well at the school, they still offer more than their number of places but won’t go to those that didn’t make the cut off in terms of standard.
Other schools must massively over offer, as they are definitely back up schools for a lot of DC. So there is plenty of hope. Good luck.

Yes they over offer.
Even the most popular know most kids sitting their exam have sat 3+ others too which might be equally popular, so they over offer. It's a difficulty science to calculate how many will accept and avoid under or over filling. No school wants to go to waiting list because by the deadline time most people have accepted somewhere else and they often have to go far down the list to those they are less keen to have.

I've know some very good but not quite top tier schools have to over offer by 4x places because they never fill despite huge numbers sitting. They simply remain a back up for loads and every year see lots of enthusiastic students at their exams and in interview who then turn them down. Essentially they become non-selective as in rider to fill they need to make offers to all applicants apart from a tiny number they really really don't want.

Without knowing the schools it is difficult to say, but generally yes. My experience is of North London Indies, which might give a skewed picture. We were told that schools were very aware that candidates would sit for more than one school and therefore needed to over offer quite substantially to fill all their places.