A-level grade boundaries are the minimum raw mark (uniform mark equivalent) a student needs on a paper or component to be awarded each grade, A* down to E. Exam boards set them after results are marked each year, using a process called comparable outcomes, so a 68% might earn an A one year and a B the next depending on how hard that year's paper was.
How A-level grades are actually calculated
Students don't sit an exam and get told "you need 80% for an A" in advance. Instead:
- Students sit the exam papers for a subject (usually 2–3 components per subject).
- Examiners mark every script and produce a raw mark total out of the maximum available.
- After marking is complete, senior examiners and Ofqual review the paper's difficulty, compare it with previous years, and set grade boundaries — the raw mark needed for each grade.
- Each student's raw mark is checked against those boundaries to determine their final grade (A*, A, B, C, D, E, or U for unclassified).
This is different from many other qualifications where the pass mark is fixed in advance. A-level boundaries are set retrospectively, specifically so that a paper which turns out to be unusually hard (or easy) doesn't unfairly punish (or reward) an entire cohort.
Why grade boundaries move every year
The principle behind this system is called comparable outcomes. Ofqual and the exam boards aim to keep the overall proportion of students achieving each grade broadly stable from year to year, adjusted for genuine changes in cohort ability (for example, a stronger GCSE cohort feeding through two years later should produce slightly stronger A-level results).
In practice this means:
- If a paper is harder than usual, fewer raw marks are needed for each grade — the boundary drops.
- If a paper is easier than usual, more raw marks are needed — the boundary rises.
- National grade proportions (the percentage of students nationally getting each grade) stay relatively steady, even though the exact mark needed for an A can shift by several marks year on year.
This is why students and parents often see headlines like "grade boundaries lower this year" — it reflects paper difficulty, not a change in what an A-level "means".
How raw marks convert to a UMS-style grade today
Since 2017 (England), A-levels have moved to linear assessment, meaning most subjects are marked entirely at the end of the two-year course rather than in modules, and the old UMS (Uniform Mark Scale) conversion has largely been phased out for reformed linear A-levels. Instead:
- Each exam board sets grade boundaries directly in raw marks for each paper/component after marking.
- Component raw marks are added together (weighted by their proportion of the qualification) to give a total.
- That total is compared against the overall subject grade boundaries to determine the final grade.
Some legacy or unreformed qualifications (and other level 3 qualifications sat alongside A-levels) may still reference UMS-style scaling, but for standard reformed A-level subjects, boundaries are published as raw marks per component and per overall subject grade.
Where to find grade boundaries
Each exam board publishes grade boundary documents after every results day (usually mid-August):
| Exam board | What's published |
|---|---|
| AQA | Grade boundaries by subject/paper, downloadable PDF tables |
| Pearson Edexcel | Grade boundary tables per subject and series |
| OCR | Grade boundaries plus statistics reports |
| WJEC/Eduqas | Boundaries for Welsh and English-entry candidates |
Boundaries are specific to the exam board and series (e.g. summer 2026), not standardised across boards — so the same raw mark on an AQA Chemistry paper and an OCR Chemistry paper will not necessarily convert to the same grade.
Grade boundaries and re-marks
Because boundaries sit only a handful of raw marks apart at the top end (often 2–4 marks between A* and A on a given component), close calls are common. If a student's total is one or two marks below a boundary, a review of marking (formerly "remark") can occasionally shift the outcome — but only if a genuine marking error is found, not because the student or school disagrees with where the boundary was set. Boundaries themselves are not something an individual school can challenge; they are set nationally for the whole cohort sitting that paper.
What this means for revision and results day
- Don't fixate on a single "safe" percentage. Because boundaries move, a target of "I need 75% for an A" one year might be closer to 70% or 80% depending on how the papers landed.
- Marginal marks matter. A handful of raw marks either way can be the difference between grades, so exam technique (following mark scheme conventions, showing working, using command words correctly) has outsized value near boundaries.
- UCAS offers are usually set as final grades, not raw marks. Universities condition offers on A*-E grades (e.g. AAB), not on specific percentages, so students don't need to track boundaries themselves during revision — the exam boards do that conversion after the exam.
Frequently asked questions
How are A-level grade boundaries decided?
Exam boards and Ofqual set grade boundaries after marking is complete, using a process called comparable outcomes that aims to keep national grade proportions broadly stable year on year while accounting for paper difficulty and genuine shifts in cohort ability. Senior examiners review scripts around each proposed boundary before it is finalised.
Why are A-level grade boundaries different every year?
Boundaries shift because exam papers vary slightly in difficulty from year to year, even when written to the same specification. Setting boundaries after marking — rather than fixing a pass mark in advance — lets exam boards correct for a harder or easier paper so results stay comparable across years.
Do all exam boards use the same grade boundaries?
No. AQA, Pearson Edexcel, OCR and WJEC/Eduqas each set their own grade boundaries for their own papers, so the same raw mark on two different boards' versions of a subject will not necessarily produce the same grade. Boundaries also differ by exam series (e.g. summer 2025 vs summer 2026) for the same board and subject.
Can a school challenge where a grade boundary is set?
No. Grade boundaries apply nationally to every student who sat that specific paper and series, so an individual school or student cannot request the boundary itself be moved. What can be requested is a review of marking for an individual script, which corrects marking errors rather than adjusting the boundary.
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