How Many Questions Can You Get Wrong on the Driver Theory Test? (2026)
2026-08-31
Five, out of forty
The RSA Driver Theory Test for category B is 40 questions, and the pass mark is 35 correct. That is 87.5%, and it leaves exactly five wrong answers. The sixth fails you.
Five is a thinner margin than most candidates assume when they hear “about 87%”. It is one wrong answer per eight questions, sustained across the whole paper, with no allowance for a bad patch in the middle.
At €45 per attempt, Ireland is also among the more expensive theory tests in Europe, which makes a scraped pass an unattractive strategy.
Why the five vanish quickly
Mistakes concentrate rather than scatter. Someone shaky on road markings will not lose a single mark there — they will lose three or four, because the RSA bank returns to markings repeatedly across 40 questions.
That concentration is what converts a comfortable-feeling 85% into a fail. The overall knowledge gap is narrow but it is clustered, and a 40-question paper is long enough to find the cluster.
Which means fixing one weak category is usually worth more marks than another general pass over material you already mostly know.
The categories that cost most
Road markings and traffic signs together account for the largest share. The Irish sign system uses distinct shapes and colours for regulatory, warning and information signs, and questions test the system rather than only the familiar examples.
Right of way at junctions and roundabouts comes next, particularly where a turning vehicle meets oncoming traffic — simple to state, easy to invert under exam pressure.
Third is the legal and documentation block: insurance, NCT, tax and licence requirements. Dry, memorisable, reliably present, and routinely skipped.
Fourth, the vulnerable road user material — cyclists, pedestrians and motorcyclists, along with safe following distances in poor conditions. It feels like common sense until a question asks for a specific distance.
Practising to a buffer
Aim for one or two wrong in practice rather than five. Exam nerves and unfamiliar phrasing reliably add a couple of errors, and that has to come out of a margin built beforehand.
Record which category each miss came from instead of only the score. Three mocks at 36/40 say almost nothing; three mocks where every miss was a road-marking question say exactly what to study.
Use full 40-question mocks rather than short quizzes. Short sets diagnose weak areas well but misrepresent both the arithmetic and the concentration required.
Clear three consecutive full mocks at 37 or better and the test stops depending on which questions turn up. At €45 a go, that is worth the extra evening.
FAQ
How many questions can you get wrong on the Driver Theory Test?
Five. The category B test is 40 questions and you need 35 correct to pass.
What is the pass mark for the Irish theory test?
35 out of 40, which is 87.5% — one of the higher pass marks in Europe.
How much does the Driver Theory Test cost?
€45 for category B (car), and the same again for each subsequent attempt.
How soon can I resit if I fail?
There is no fixed rule, though the RSA recommends waiting around three business days before booking again.
Sources: RSA — Driver Theory Test