One-third of the question's marks per wrong answer
For each wrong answer, one-third of the marks assigned to that question is deducted: 0.66 marks in GS Paper I (2-mark questions) and 0.83 marks in CSAT Paper II (2.5-mark questions).
Official marking scheme
UPSC Negative Marking — How the Prelims Marking Scheme Works
Both UPSC Prelims papers deduct one-third of a question's marks for every wrong answer: 0.66 marks in GS Paper I and 0.83 marks in CSAT Paper II. Unanswered questions cost nothing. The rule comes from the “Penalty for wrong answers” note in Appendix-I of UPSC Examination Notice No. 05/2026-CSE.
Marks per question and penalty per paper
Both papers are objective-type (MCQ). Each wrong answer deducts one-third of the marks assigned to that question.
| Paper | Questions | Total marks | Marks per question | Wrong answer | Unanswered |
|---|---|---|---|---|---|
| GS Paper I | 100 | 200 | 2 | −0.66 (one-third of 2) | 0 |
| CSAT Paper II | 80 | 200 | 2.5 | −0.83 (one-third of 2.5) | 0 |
The four penalty rules
Marking two answers counts as wrong
If you give more than one answer to a question, it is treated as a wrong answer and draws the same one-third penalty — even if one of the marked answers happens to be correct.
Blank questions cost nothing
There is no penalty for a question you leave unanswered. Skipping is always better than a blind guess with no elimination — a wrong 2-mark answer swings your score by 2.66 marks versus a blank.
The same rule applies to both Prelims papers
GS Paper I and CSAT Paper II both carry the one-third penalty. In CSAT you only need 66.67 of 200 marks to qualify, so reckless attempting is the main way candidates fail it.
Worked example
What 80 attempts really score
Say you attempt 80 GS questions and get 55 right and 25 wrong. You earn 55 × 2 = 110 marks, lose 25 × 0.66 = 16.5 marks, and net 93.5 — comfortably above most recent General-category cutoffs.
The same 80 attempts with 45 right and 35 wrong nets only 90 − 23.1 = 66.9. Accuracy, not attempt count, decides the paper.
When guessing pays
The elimination math
A blind guess across four options expects 0.25 × 2 − 0.75 × 0.66 = 0 — pure variance. Eliminate one option and the expected value turns positive (about +0.22 marks); eliminate two and it rises to about +0.67.
Rule of thumb: attempt every question where you can strike out at least one option; leave the rest blank.
Which marks count — and which don't
GS Paper I decides the Prelims cutoff and who advances to Mains. CSAT Paper II is qualifying only at 33% — 66.67 of 200 marks. Prelims marks do not count toward the final merit list; final merit is based on Mains and Interview.
That makes net score after penalties the only number that matters. Practise with timed mock tests that apply the same one-third deduction, so your practice scores predict your real ones.
Official sources
Every figure on this page is cited to this UPSC document:
- UPSC Examination Notice No. 05/2026-CSE, dated 04.02.2026 — Civil Services (Preliminary) Examination, 2026
Appendix-I: the two-paper scheme, the CSAT 33% qualifying rule, and the 'Penalty for wrong answers' note that defines the one-third deduction.
Related UPSC Prelims resources
UPSC Prelims exam pattern
The full two-paper structure: questions, marks, duration, and qualifying rules.
Open resource →UPSC Prelims mock test
Timed mocks scored with the same one-third penalty, so your practice score is honest.
Open resource →UPSC Prelims cutoff
Official year-wise cutoffs — see what a safe net score looks like after negative marking.
Open resource →Previous year questions
Practise real UPSC questions and learn when to attempt, eliminate, or skip.
Open resource →Frequently asked questions
- Is there negative marking in UPSC Prelims?
- Yes. Both Prelims papers have negative marking: one-third of the marks assigned to a question is deducted for each wrong answer — 0.66 marks per wrong answer in GS Paper I and 0.83 in CSAT Paper II. There is no deduction for unanswered questions.
- How many marks is each question in UPSC Prelims?
- GS Paper I has 100 questions for 200 marks, so each question carries 2 marks. CSAT Paper II has 80 questions for 200 marks, so each question carries 2.5 marks.
- What is the negative marking in CSAT?
- CSAT questions carry 2.5 marks each, so a wrong answer deducts one-third of that: 0.83 marks. CSAT is qualifying only — you need 66.67 marks (33% of 200) — but penalties from over-attempting are a common reason candidates miss it.
- What happens if I mark two answers for one question?
- It is treated as a wrong answer and draws the standard one-third penalty, even if one of the marked answers is correct.
- Is there negative marking for questions left blank?
- No. Unanswered questions score zero with no penalty. That is why guessing without eliminating any options is a losing strategy, while a 50-50 elimination guess is mathematically favourable.
- Do UPSC Prelims marks count in the final merit list?
- No. Prelims is a screening stage — GS Paper I decides who qualifies for Mains against the cutoff, and CSAT must be qualified at 33%. Final merit is based on Mains and Interview only.
- Is there negative marking in UPSC Mains?
- The Mains papers are descriptive (written answers), so the objective-type penalty does not apply there. The one-third negative marking applies to the two objective Prelims papers.
Practise with the real penalty applied
Timed mock tests scored with one-third negative marking, PYQ drills, and accuracy analytics.