What voiding actually does
At the end of your exam, before you ever see a score, you can void. Your score is never scored or reported to any school, and it never appears on your record. The attempt itself still shows on your testing history as a void. So voiding trades a real data point for the guarantee that no school sees this particular day.
When voiding is worth considering
Consider it if something genuinely went wrong that clearly hurt your performance: you got sick mid exam, had a panic episode you could not recover from, or faced a real emergency. Consider it if you are confident, for a concrete reason and not a vague feeling, that this day landed far below your practice range.
When not to void
Do not void because you “felt bad.” Almost everyone feels bad walking out of the MCAT. The exam is built to leave you uncertain, and your read on your own performance right after finishing is one of the least reliable signals you have. The strongest sections often feel the worst, because the hard questions are the ones you remember.
Here is the honest version of the usual claim. It is common for test takers to feel they did worse than they did, and to underestimate their score in the minutes after finishing. I am not going to hand you a precise number of points for that gap, because the reliable finding is the direction, not a tidy figure. The direction is enough: do not make a permanent decision on the least reliable data you will ever have about this exam.
A data based way to decide
If your practice average, from official full lengths taken under realistic conditions, sits within about three points of your target, and nothing unusual happened on test day, do not void. The typical gap between honest practice scores and the real thing is small. Trust the preparation over the adrenaline.
If you are already eyeing a retake
If you are leaning toward retaking anyway, voiding can feel like relief, but it also erases information. A real score tells you exactly where you stand and which sections to attack. That is planning fuel for a smarter retake. A void gives you peace of mind and a blank space where useful data would have been. Weigh which one you actually need more.