What is an exam centre and how is it decided?

The exam centre is the institution where you actually sit the paper, and it is often not your own. The board assigns it, and neither the student nor the institution gets to choose.

The reason it is not your own institution is impartiality. Holding the exam away from familiar teachers and familiar surroundings reduces the scope for influence. It is also why the officers on duty at a centre are usually from elsewhere.

Assignment weighs geography against capacity — how many candidates, in which area, and how many an institution can seat. Students from one institution usually land at the same centre, though a large cohort can be split.

One practical piece of advice: visit the centre the day before. Knowing which gate, which building and how long the journey takes removes a lot of avoidable stress on the first morning. Requests to change centre are generally not entertained, so plan around the one you were given rather than hoping to move it.