parent guides

The ISEB Pre-Test, explained: what it is, how it works and who needs it

If your child is heading for an independent senior school - for Year 7 or the traditional Year 9 (13+) entry - they will almost certainly meet the ISEB Common Pre-Test along the way. It is online, adaptive, and nothing like a school exam. Here is what it actually involves.

Reviewed 20 October 2026 against kent.gov.uk

What the ISEB is

ISEB stands for the Independent Schools Examinations Board - the organisation that has set entrance exams for UK independent schools since 1904. It runs two very different assessments that parents routinely confuse:

When parents say "the ISEB", they almost always mean the Pre-Test - it is the gatekeeper. Common Entrance comes later and, at most schools, confirms rather than decides.

What the Pre-Test is for

More than 70 of the UK's most selective independent senior schools use the Pre-Test as their first (and sometimes only) academic filter. It is used for both main independent entry points: schools that admit at 11+ into Year 7, and the traditional boarding and day schools that admit at 13+ into Year 9 - Eton, Harrow, Tonbridge School and their peers all sit in the second group.

One sitting covers every school. Since autumn 2022, parents register their child directly on the ISEB website (free), list the schools they are applying to, and the same result is shared electronically with all of them. A child can only sit the Pre-Test once per academic year - if they somehow sit it twice, the first result stands. You still apply to each school separately; the Pre-Test does not replace the school's own application process, it feeds into it.

How the test works

The Pre-Test is taken on a computer, usually at the child's current school (prep schools administer it routinely) or at the senior school being applied to. It is commissioned from GL Assessment - the same stable of tests behind much of the 11+ world - and is adaptive: every child starts with a medium-difficulty question, and the test gets harder when they answer correctly and easier when they don't. Finding it harder as it goes on is a good sign, not a bad one.

Four separately-timed sections, around 2 hours 15 minutes in total:

The sections can be sat together or on separate days - the administering school decides. Three quirks catch children out: there is no back button (every answer is final), the test is multiple-choice throughout, and a visible timer and progress bar run on screen. Pen and paper are allowed for workings, and a short set of example questions plays before the real thing starts.

How it's scored

Results come out as a Standardised Age Score (SAS) per section - the same 69-to-141-style standardised scale used across UK admissions testing, where 100 is average and each point accounts for age within the year group. Because it's age-standardised, an autumn-born and a summer-born child are compared fairly, and sitting the test early in the window carries no disadvantage. Scores go straight to the schools; parents usually hear the outcome via the school's own offer process rather than a results letter.

When it happens

Schools ask candidates to sit the Pre-Test between 1 October and 1 February, most commonly in November of Year 6. Each school sets its own date within that window, which is why registration with ISEB should happen early in the autumn term of Year 6 - some schools close their lists before half term. For 13+ entry schools, the whole timeline runs early: register in Year 5 or the start of Year 6, Pre-Test in Year 6, conditional offer, then Common Entrance in Year 8 to confirm.

ISEB vs the Kent Test: which does your child need?

Simple rule: state grammar schools use the Kent Test; independent (fee-paying) senior schools use the ISEB route. The Kent Test is a fixed paper-based exam sat by everyone on one September day in Year 6, scored against a published pass mark. The Pre-Test is online, adaptive, spread across an autumn window, and scored school-by-school with no universal pass mark.

Plenty of Kent families do both - a grammar as the state option, an independent as the insurance or first choice. The four subjects overlap heavily (English, maths, verbal and non-verbal reasoning in both), so preparation carries over almost completely. The main extra the Pre-Test demands is comfort with the adaptive, on-screen, no-going-back format - which is exactly how our own ISEB pathway is built: adaptive missions and mocks in the same style, so the real test feels like a familiar Tuesday.

What about Year 9 (13+) entry?

If you're aiming at a school that starts at Year 9, the Pre-Test is usually still the key exam - but it happens in Year 6, a full two to three years before entry, which surprises many parents. The sequence is: Pre-Test in Year 6 or early Year 7, a conditional offer, then Common Entrance papers (or the school's own exams) in Year 8 to confirm the place. Some famous names have dropped Common Entrance and rely on the Pre-Test plus their own assessments and interviews, so always check the current route with each school.

For state grammar schools, there is no 13+ version of the Kent Test. Joining a Kent grammar after Year 7 means an in-year (casual) application direct to the school, and most Kent grammars assess in-year applicants with the CAT4 cognitive abilities test rather than the Kent Test - typically wanting an average standardised score around 114+, with some schools (Weald of Kent among them) asking for 118 in every section. Places at that stage depend entirely on vacancies, which are rare.

Questions parents ask

Sources: ISEB (iseb.co.uk - Common Pre-Test and Common Entrance guidance, checked 20 October 2026), GL Assessment, and published admissions policies of Kent grammar schools offering in-year (CAT4) entry including Weald of Kent Grammar School and Maidstone Grammar School.