Parents applying for 11+ entry in September 2026 have, in the main, already made their registrations. The cycle for 2026 entry closed, at most London schools, some time in the autumn of 2025 — and a full term earlier than many families had planned for when they started thinking about the process in Year 4.
This is not, to be clear, a single coordinated move. No body has the authority to coordinate it. But compared to 2024 entry, the pattern across the ten schools we track most closely is unambiguous. Deadlines have shifted forward; the assessment window has tightened; the ISEB Common Pre-Test replaces, at more schools, what used to be individual pre-tests run by each school's own maths and English departments.
What the ISEB window now looks like
For 2026 entry, the ISEB Common Pre-Test session opened in September 2025 and closes on Friday 12 June 2026, with the last testing day on Friday 29 May 2026. [ISEB, Common Pre-Tests]
Several London schools set their own internal deadlines well before that national window closes. The Harrodian requires the ISEB to be complete by Monday 1 December 2025 for 11+ entry; JAGS by 8 December 2025. A number of others — some of which publish the deadline, others of which do not — cluster around 30 November or the first week of December. [Harrodian Admissions; Good Schools Guide / London 11+ coverage]
The practical consequence: a family first engaging with the process in October of a child's Year 6 will, in many cases, find they have already missed the registrar's cut-off at their first-choice school. That is not a change in the school's policy; it is a change in the operational density of the autumn term.
"Our registrar called in July. The cut-off for the ISEB was the Friday before half-term, and she wanted to know if we were serious before she put us in the book." — composite, drawn from Mumsnet 11+ threads, central and north London boards
Why it has happened
Three reasons, none of them sinister.
First, the ISEB format itself has matured. Schools that once ran their own pre-tests have, increasingly, adopted the Common Pre-Test as their single gate, which moves their assessment calendar onto ISEB's timetable rather than their own academic diary. That is a material change: a school setting its own 11+ paper can schedule it for February; a school using the ISEB must work to ISEB's autumn/winter window.
Second, the number of applications has not fallen. Despite the post-VAT pupil drop recorded in the ISC 2025 Census — down 2.4 per cent nationally — London 11+ applications at the most-applied-to schools remained broadly flat, and at two schools we can confirm, slightly increased. Registrars, under pressure, have pulled deadlines forward to create processing time. [ISC Census 2025]
Third, the industry around 11+ preparation has become extremely effective at flagging deadlines to the families it already works with. Tutoring agencies now brief their Year 4 families on 2026 registrations, creating a forward pressure that registrars then respond to by moving cut-offs earlier still. It is a quiet arms race.
What to do if you are newly in the cycle
For 2027 entry (current Year 5), the useful sequence is now:
- Spring of Year 5: longlist of 6 to 10 schools. Check each website's admissions calendar — not each school's central brochure, which is often a term out of date.
- Summer of Year 5: attend open days. Register interest formally where the school allows it; in several cases registration now opens on or before 1 September of Year 6.
- Michaelmas of Year 6: complete ISEB Common Pre-Test during the school's preferred window. Most London schools now want this done by end of November.
- Spring of Year 6: school-specific written papers and interviews at those schools that still run them (for 11+, a shrinking subset; for 13+, still the norm).
The argument for starting this sequence a year earlier than parents used to is no longer hypothetical.
Sources: ISEB Common Pre-Test published timetable; Harrodian Admissions (2026 entry); JAGS admissions page; Good Schools Guide London coverage; ISC Census 2025. Mumsnet fragments are composite and drawn from public Secondary-board threads, autumn 2025.