If you are searching for IGCSE Biology grade boundaries for 2026, you are in the right place. All data in this guide is sourced directly from the official Cambridge International IGCSE grade threshold tables page , including the June 2025 Biology threshold table (PDF) and the November 2025 Biology threshold table (PDF). Bookmark this page, share it with your biology teacher, and come back after results day in August 2026 to see how close the prediction lands.

What are grade thresholds in IGCSE Biology?

Cambridge International (CIE) calls them grade threshold tables, but students and teachers commonly call them grade boundaries. They are the minimum total mark a student must score — after all papers are combined and weighted — to be awarded each grade from G up to A*. For IGCSE Biology (syllabus code 0610), the most widely sat combination of papers for extended candidates is Paper 2 (Multiple Choice Extended, 40 marks, 45 minutes), Paper 4 (Theory Extended, 80 marks, 75 minutes), and Paper 6 (Alternative to Practical, 40 marks, 60 minutes). Cambridge labels this combination Option CY in its official threshold tables. The three papers combine for a maximum weighted total of 200 marks, and all grade boundaries in this guide refer to that 200-mark scale unless otherwise stated.

One point students must understand from the start: Cambridge does not award A* at the level of individual components. A* only exists at the overall weighted total. There is no such thing as getting A* on Paper 4 in isolation. As Cambridge's own awarding guidance explains, boundaries are set by reference to the actual performance of candidates in each sitting — not to a fixed percentage. This is why boundaries shift between sessions and why comparing your score to a previous year's threshold is only meaningful once you understand the cohort context behind that number. For students preparing for June 2026 with live expert tuition, the IGCSE Biology course at chem-bio.info includes past paper practice, mark scheme technique, and Paper 4 structured answer clinics aligned to the current 0610 syllabus.

IGCSE Biology grade thresholds: June 2023 to November 2025

The overall picture across six sessions

The official grade threshold tables tell a story of remarkable stability. For Option CY across the past three years, the A* boundary has moved within a range of just 13 marks on a 200-mark scale — from a low of 161 in November 2023 to a high of 174 in June 2025. Cambridge's awarding process is deliberately calibrated for this kind of stability, and students should be equally sceptical of anyone predicting a sudden collapse or a sudden spike in the boundaries for 2026.

Paper-by-paper breakdown: minimum marks per grade

Paper 2 — Multiple Choice Extended (40 marks)

Paper 2 is the shortest paper and the only one where every mark is binary — right or wrong. There are no partial marks, no method marks, and no extended writing. Across all six sessions from June 2023 to November 2025, the A boundary on Paper 2 has sat between 30 and 33 out of 40 — a range of just 3 marks, making it the most predictable single component in the entire combination. All past Paper 2 papers and mark schemes are available at Physics & Maths Tutor's IGCSE Biology Paper 2 library.

To perform at grade A on Paper 2, students need to score between 75% and 82.5% — that is 30 to 33 correct answers out of 40. To secure a C, students need roughly 21 to 25 out of 40 (52.5%–62.5%). This is achievable with solid revision of core content alone, making Paper 2 one of the more forgiving components for students consolidating their knowledge at the last minute.

Paper 4 — Theory Extended (80 marks)

Paper 4 is the most heavily weighted component in the entire combination. At 80 marks it contributes twice as much to the final total as either Paper 2 or Paper 6. Structured questions, data analysis, and extended response items test not just knowledge recall but the ability to apply biological understanding in context — explaining mechanisms, interpreting graphs, evaluating experimental design, and constructing arguments using precise scientific language. Across the six sessions, the A boundary on Paper 4 has shown the clearest upward trend of any component. All past Paper 4 papers and mark schemes are available at Physics & Maths Tutor's IGCSE Biology Paper 4 library.

The A boundary has risen by 8 marks in two years — from 47 in June 2023 to 55 in June 2025. Students should plan to target at least 50 out of 80 (62.5%) to be competitive at grade A, and should be aiming for 54 to 58 out of 80 if an A* overall is the goal. Scoring at C-level on Paper 4 while targeting A* overall is not viable. Paper 4 must be strong, and it must be the primary focus of revision time for any student aiming above grade B.

Paper 6 — Alternative to Practical (40 marks)

Paper 6 replaces the practical examination for students who do not sit Paper 5. It tests experimental design, data interpretation, graph work, and the evaluation of biological investigations. Many students underestimate this paper, treating it as less important than Paper 4 — a costly mistake given it carries the same weighting as Paper 2. The grade thresholds on Paper 6 across the past three years have been extraordinarily stable — arguably the most predictable of all three papers. All past Paper 6 papers and mark schemes are available at Physics & Maths Tutor's IGCSE Biology Paper 6 library.

The A boundary on Paper 6 has not left the range of 30 to 34 out of 40 in any of the six sessions. The C boundary has barely moved outside 21 to 23. Students who practise past Paper 6 questions consistently should find this paper highly manageable. The skills it tests — planning experiments, drawing graphs, identifying variables, evaluating methods — are learnable, repeatable, and heavily rewarded by structured revision.

June vs November: which session gives the better chance of an A*?

This is one of the most common questions from students and parents, and the data gives a nuanced answer. Looking at the A* boundary for Option CY across the three years, June sessions have trended higher — June 2025 reached 174 out of 200, the highest recorded in this dataset. November sessions have consistently offered a slightly lower A* threshold, ranging from 161 to 172, compared to 164 to 174 in June.

Why does this happen? The June cohort is larger and, on average, includes more students who have completed the full two-year IGCSE programme in a single sitting. November retakers and a smaller overall cohort mean Cambridge calibrates the November thresholds differently. Neither session is objectively easier — the papers themselves vary in difficulty — but historically, November has required fewer total marks to achieve A*. That said, this should not drive a student to choose November over June purely for boundary reasons. The preparation window, the school teaching cycle, and university application timelines are all more important factors in that decision.

What the grade thresholds mean for your Biology revision strategy

Targeting A*

To reach A*, students need approximately 164 to 174 out of 200 depending on the session. A working target for June 2026 that accounts for the upward trend is 172 to 175 out of 200. Across three papers, that means approximately 33–36 out of 40 on Paper 2 (82%–90%), 52–58 out of 80 on Paper 4 (65%–72%), and 32–35 out of 40 on Paper 6 (80%–87%). Paper 4 is the biggest leverage point. An extra five marks on Paper 4 is worth more to your overall total than five extra marks on Paper 2 or Paper 6, because Paper 4 carries double the raw marks.

Targeting A

Students aiming for grade A need approximately 138 to 149 out of 200. A working target is 30–32 out of 40 on Paper 2 (75%–80%), 45–50 out of 80 on Paper 4 (56%–62%), and 30–32 out of 40 on Paper 6 (75%–80%).

Targeting C

Students consolidating for a C need approximately 89 to 101 out of 200. That is achievable with 21–23 out of 40 on Paper 2 (52%–57%), 28–33 out of 80 on Paper 4 (35%–41%), and 21–23 out of 40 on Paper 6 (52%–57%).

Grade threshold prediction for IGCSE Biology June 2026

Based on three years of data across six sessions, here is a data-grounded prediction for June 2026 thresholds on Option CY. The methodology takes the mean of the two most recent June sessions — June 2024 and June 2025 — as the primary anchor, then applies a conservative adjustment to account for the mild upward trend observed on Paper 4.

The most important prediction here is for Paper 4. If the upward trend in the Paper 4 A boundary continues — it has risen from 47 in June 2023 to 55 in June 2025 — students should be prepared to score 55 to 58 out of 80 to sit comfortably at grade A level on that paper. These predictions are estimates based on historical data. Always refer to the official Cambridge International grade threshold tables after results are published in August 2026.

The most important paper you can still influence: Paper 2

For students sitting their final paper — Paper 2 — in the June 2026 series, this is the most actionable section of this entire guide. Paper 2 is 40 multiple choice questions. You cannot lose marks for wrong answers. Every question you get right is a direct addition to your overall total. There is no extended writing, no graph to draw, no practical to manage — just knowledge and application in its purest form.

The data says an A on Paper 2 requires between 30 and 33 correct answers out of 40. That is getting at least 75% of questions right, and across six consecutive sessions the threshold has never dropped below 30 or risen above 33. This is a narrow, predictable target — and that predictability is a gift. A student who has completed Papers 4 and 6 has already revised the entire syllabus. Paper 2 revision is not about learning new content. It is about tightening accuracy on content already known. The most common Paper 2 errors come from misreading questions, confusing similar biological processes such as mitosis versus meiosis or active transport versus diffusion, and dropping marks on calculation-based MCQs involving photosynthesis rates or population data.

Frequently asked questions

Is the A* boundary getting harder to reach each year?

For the June series, there is a mild upward trend — particularly on Paper 4. The A* overall boundary rose from 164 in June 2023 to 174 in June 2025. However, this reflects a combination of paper difficulty calibration and cohort performance, not a runaway escalation. Students who target 173 to 175 out of 200 as their revision benchmark are working from a sound, data-driven position.

Do grade thresholds differ between Paper 5 and Paper 6?

Yes. Option BY uses Paper 5, which is the actual practical examination, while Option CY uses Paper 6, the alternative to practical. The overall thresholds differ between these options. This guide focuses on Option CY with Paper 6, as it is the route available to most international school students, including those in Kuwait and across the GCC region. Students in schools where Paper 5 is sat should refer to the Option BY boundaries in the official threshold tables.

Can a strong Paper 2 compensate for a weak Paper 4?

Partially, but not fully. Paper 4 carries 80 raw marks versus Paper 2's 40. A student who scores poorly on Paper 4 and achieves a near-perfect Paper 2 score still has a severely restricted overall total. Paper 4 is the dominant component. Paper 2 can move a grade by one boundary — from B to A, or from C to B — but it cannot bridge a two or three-grade gap caused by a very low Paper 4 performance.

When will the June 2026 grade thresholds be published?

Cambridge typically publishes grade threshold tables on the same day as results — usually mid-August. The exact date for August 2026 will be confirmed by Cambridge International closer to the time.

Where can I find the official grade threshold tables?

All official Cambridge IGCSE Biology (0610) grade threshold tables — for June and November sessions going back several years — are published directly at the Cambridge IGCSE grade threshold tables page.

Summary: what every IGCSE Biology student needs to know

• The A* boundary for IGCSE Biology (0610) Option CY has ranged between 161 and 174 out of 200 across the past three years and six sessions.
• Paper 4 is the highest-leverage component — it carries double the marks of Papers 2 and 6 and should receive proportionally more revision time from any student targeting A or A*.
• Paper 2 thresholds are the most stable of the three papers, with the A boundary never leaving the range of 30 to 33 out of 40 across six consecutive sessions.
• Paper 6 thresholds are equally predictable, with the A boundary sitting between 30 and 34 in every session — the most learnable component in the combination.
• June sessions have trended toward slightly higher A* thresholds than November sessions, though the gap is not always large.
• For June 2026, a reasonable A* target is 172 to 175 out of 200 — approximately 33 out of 40 on Paper 2, 55 out of 80 on Paper 4, and 33 out of 40 on Paper 6.
• The official 2026 boundaries will be published by Cambridge International in August 2026. Until then, the data from six sessions gives students the clearest possible picture of where to aim.

Analysis based on official Cambridge International IGCSE Biology (0610) grade threshold tables for June 2023, November 2023, June 2024, November 2024, June 2025, and November 2025. All data sourced directly from cambridgeinternational.org. For live IGCSE Biology and Chemistry tuition, revision classes, and study resources, visit chem-bio.info.