What this guide covers
- What a resit actually is
- The examination session structure
- What carries forward and what does not
- How to register for a resit
- Choosing which subjects to resit
- Timing and results
- Frequently asked questions
What a resit actually is
An IB resit, or retake, is a chance to sit one or more Diploma Programme components again in a later examination session in order to lift the final result. It is a formal process run by the International Baccalaureate rather than an informal arrangement with a school, and it follows fixed rules about timing, registration and how scores are combined. Understanding those mechanics matters, because the difference between a well planned resit and a rushed one is often the difference between a meaningful uplift and a wasted session.
The most important point to grasp early is that a candidate does not have to sit the entire diploma again. Most resit candidates repeat only the one or two subjects that fell short, keeping every other component from the original session. This selective approach is the standard route and the reason resits are far more manageable than they first appear.
The session structure
The IB runs two examination sessions a year. The May session is the larger one, taken by most schools in the northern hemisphere, while the November session serves southern hemisphere schools and acts as the natural resit window for May candidates. A student who sat in May can therefore aim for the following November, roughly six months later, or wait until the next May a year on. November candidates use the reverse pattern. The choice between the near and the far session depends on how much ground there is to make up and how much preparation time the subject realistically needs.
A candidate has up to three sessions in total, including the original, to complete the diploma, and those sessions must fall within a limited window of the first sitting. This gives most students two genuine resit opportunities, which is ample for a focused improvement in one or two subjects.
What carries forward and what does not
When a candidate resits selected subjects, the results in every component they do not repeat are carried forward automatically. If a student resits only Chemistry and Mathematics, the grades in their other four subjects, together with the Extended Essay and Theory of Knowledge, remain exactly as they were, and only the two repeated subjects are re examined. The overall points total is then recalculated using the better of the old and new grade for each repeated subject, so a resit can never lower the final score.
Internal assessment marks usually carry forward without resubmission, which means a candidate can concentrate revision on the externally examined papers. Some subjects, particularly languages, have specific rules about oral and written coursework, so the exact mechanics should be confirmed with the registering school or exam centre before committing.
Deciding whether a resit is worth it
The mechanics are only half the picture. For the full cost and benefit decision, including how universities treat repeated results, read our deeper IB diploma retakes guide, then browse the wider IB curriculum hub for context.
How to register for a resit
There are two registration routes. The first is through the candidate's original school, which can often re register its own alumni as external candidates for a future session and already holds their coursework and predicted grade records. The second is through an IB authorised examination centre acting for private candidates, which offers flexibility for those who have moved away or whose school does not support resits. Either way, the IB sets firm registration deadlines several months ahead of each session, so this step belongs in the weeks straight after results day rather than close to the exams.
Fees are charged per subject rather than as a single diploma fee, with a separate registration fee per session for private candidates. The exact schedule changes each year and varies by centre and country, so ask the registering school or centre for the current figures rather than relying on old numbers.
Choosing which subjects to resit
The clearest targets are subjects that fell well below their predicted grade, especially Higher Level subjects tied to a specific university offer. A subject two grades below prediction usually has real headroom, whereas a subject one grade below a close boundary is a more marginal case. The component breakdown issued with the original results is the best diagnostic, since it shows where marks were lost and whether the gap was in a paper that responds well to focused revision.
Most candidates leave the Extended Essay and Theory of Knowledge untouched, because improving them requires substantial rewriting for a small change in the core points. Concentrating on one or two subject papers is almost always the more efficient path.
Timing and results
May results are released in early July, giving a candidate about four months to prepare for a November resit or around fifteen months for the following May. Resit results are issued on the same schedule as first sittings, and the recalculated diploma is confirmed once the repeated components are graded. Candidates holding a deferred university place should confirm with the institution that the resit timetable fits its deadline before registering, since some courses can wait for November results and others cannot.
Frequently asked questions
How soon can you resit IB exams?
The next available session is usually the following November for a May candidate, roughly six months later, or the next May a year on. The right choice depends on how much preparation the subject needs and any university deadline you are working towards.
Do you have to resit the whole IB diploma?
No. Most candidates resit only the one or two subjects that fell short and carry forward every other component, including the Extended Essay and Theory of Knowledge, from the original session.
Can a resit lower your IB score?
No. The IB uses the better of the original and repeated grade for each subject you resit, so the recalculated total can only stay the same or improve.
How much does an IB resit cost?
Resits are charged per subject, with a separate registration fee for private candidates. The schedule changes each year and varies by centre and country, so ask your school or exam centre for the current figures.