This is an interesting point. What you’ve described is essentially the approach KCS is taking — a slow, phased transition. Girls will join from Year 3 in 2029, moving up each year and always being the oldest girls in the school. The school won’t be fully co-ed until around 2037, and girls will remain heavily outnumbered for quite some time.
Westminster’s rollout is very different. From 2026, girls will enter at Reception, Years 3, 7, and Sixth Form, with more cohorts added annually. It’s undoubtedly more complex to implement, but I actually think it creates a better environment for the girls themselves — my daughter, for instance, would feel more part of the school community from day one.
As I understand it, it works something like this:
2026. Girls in reception, Years 3, 7, 12 & 13
2027Girls in Years R, 1, 3, 4, 7, 8, 12 & 13
2028. Girls in Years R–5, 7–9, 12 & 13
2029 Girls in all years except Year 11
2030 Fully co-ed across the school
They’ve clearly thought hard about the co-ed provision, but the critical thing they still need to get right is the main entry point for girls. It is 11+, and the number of places offered should reflect that. I’d much rather my daughter join at 11, when friendships and school culture are forming, than be one of a small handful girls arriving at 13. Definitely something to think about. Well — that’s if she can secure an offer, of course!