Can You Retake IB Subjects? Rules, Timing and Strategy
Yes — up to two subjects within a year. Here are the exact rules, the November vs May/June options, and how to structure focused retake preparation.
Velocity Tuition Academy · IB Diploma · Retakes
Updated May 2026·Written by Velocity Tuition Academy·Reviewed by IB Diploma teachers with retake-preparation experience
Yes — you can retake IB subjects. The rules: up to two subjects in the May/June or November sittings within one year of the original session. This is the IB's published policy and it applies whether the student is retaking to push a grade up or to recover a structural fail. This guide covers exactly how the retake process works, when each session option makes sense, and how to plan focused preparation that actually moves the grade.
Up to two subjects can be retaken in any subsequent session.
Within one year of the original Diploma session. After one year, the entire Diploma must be re-sat.
Either May/June or November session — November sittings are more limited in subject availability, but most major subjects are offered.
The higher grade is used for the Diploma calculation. Both grades remain on the IB record, but the higher one counts.
TOK and EE can also be re-submitted under the same rules — counted as one of the two retakeable components.
CAS cannot be retaken; it is pass/fail and either complete or not at the original submission.
When to Choose November vs May/June
The two session options:
November session — exams late October to mid-November. Results in early January. Registration typically opens in June and closes in early September the year of the November sitting. Useful for students who:
Want a shorter turnaround between original results and retake.
Are not in time pressure for a January university start.
Are at a school where teacher availability for retake support is stronger in autumn than spring.
May/June session — exams May to mid-June. Results in early July. Registration typically closes in late October or November the year before. Useful for students who:
Need a full academic year of preparation (12 months from August results to May exams).
Are targeting university entry in September the year of the retake.
Can dedicate full-time effort during sixth form-equivalent intensity.
Targeted Retake — How to Plan It
The successful retake follows a focused structure:
Diagnose where the marks were lost. Request the breakdown from the original session — which papers, which questions, which command-words. The IB and the school can usually provide this. Generic "I'll just work harder" rarely closes a 1-grade gap.
Cover only the relevant content. A retake is not the IB programme over again. It is targeted preparation on the specific gaps identified.
Past paper drill from week one. Past papers from the most recent three years, sat under timed conditions, marked with mark schemes. For most subjects this is the single highest-ROI activity.
Schedule the IA refresh if applicable. Some subjects let you re-submit the IA component (typically 20-25% of the grade); others lock it. Check with the IB coordinator.
Tutor 1-on-1 if the gap is specific. A focused 8-12 session programme in the gap subject usually beats a return to general classroom teaching for retake purposes.
Subjects That Are Most Often Retaken
Across the global IB cohort, the most commonly retaken subjects are:
Maths AA HL — the most demanding HL subject; gap from 5 to 6 or 6 to 7 is the typical retake.
Sciences HL (Chemistry, Physics, Biology) — medical and engineering applicants need 6 or 7 at HL; retakes from 5 or 6 are common.
Economics HL — pushing 6 to 7 for LSE/competitive Economics admissions.
English Language and Literature HL — for international students whose university English-proficiency requirement depends on the IB grade.
TOK and EE — improving A-B or B-A to gain 1 or 2 more bonus points; surprisingly effective lever.
Universities and Retakes
How retakes affect university applications:
UK universities generally accept retake grades. The retake grade is what counts for the offer. Some highly competitive courses (Oxbridge Medicine, particularly) may consider the original grade alongside the retake; most do not.
US universities generally read the retake favourably as evidence of growth, especially if the student shows consistent improvement. The application can be updated mid-cycle with the new grade.
Canadian and Australian universities accept retake grades as standard.
Some courses with structural requirements (HL subjects at specific grades) are explicit that the retake grade satisfies the requirement.
The honest realism: a retake is a stronger application than a single below-target sitting, but it is not invisible. Universities read it as evidence of two things — the original grade was below target, and the student worked to fix it. Most read this as a positive signal.
Planning an IB retake?
Our 1-on-1 IB tutors specialise in focused retake preparation — diagnostic-first, mapped against the November or May/June timeline, with past-paper drill from week one. Free trial assesses where the marks are being lost.
Yes. The IB allows students to retake up to two subjects in the November or May/June session within one year of the original sitting. The higher grade is used in the Diploma calculation. Both grades remain on the IB record but only the higher counts.
Up to two subjects in any single retake session. If a student needs to retake more than two subjects, they must re-sit the full Diploma in a subsequent session. The two-subject limit is per session, not per year.
Yes. The Extended Essay (EE) can be re-submitted under the same retake rules — counted as one of the two retakeable components. The higher grade is used. Students who scored B or C on the first attempt sometimes target a re-submission for the bonus-point benefit.
In the next November or May/June session within one year of the original Diploma session. November sittings have shorter turnaround (3-4 months from results); May/June sittings give a full academic year of preparation. Registration deadlines: typically September for November, late October/November the previous year for May/June.
Most universities accept retake grades and use them in admissions decisions. UK universities accept the higher grade; US universities generally read retakes favourably as evidence of growth. Some highly competitive courses (Oxbridge Medicine particularly) may consider the original grade alongside; most do not. The retake is read more positively than a single below-target sitting.
For a single-subject retake from a 5 to a 6 or a 6 to a 7: typically 12-20 weeks of focused work, with 4-6 hours a week of subject-specific preparation plus 1-2 hours weekly of timed past-paper practice. Starting earlier (immediately after results) gives more flexibility. Cramming a retake in the final 4-6 weeks rarely changes the grade.
