UPSC Syllabus 2027: Prelims & Mains Subject-wise

The UPSC syllabus for the Civil Services Examination covers three stages: the Preliminary exam, the Main exam and the Personality Test, also called the Interview. The syllabus is broad, but it is also stable, so a clear map saves months of confusion. According to the UPSC calendar, the notification for the 2027 exam is due on 13 January 2027, and the Prelims is planned for 23 May 2027. First, this guide explains the three stages. Then it lists every paper with its topics and marks.

UPSC Syllabus Overview: Three Stages

The exam runs once a year, and it selects officers for services such as the IAS, IPS and IFS. The three stages follow each other, so you must clear one to reach the next. Meanwhile, the final rank depends on the Main exam and the Interview only.

The stages are the Preliminary exam (objective), the Main exam (descriptive) and the Personality Test. Therefore, your preparation has to move from broad reading to deep answer writing.

UPSC Prelims Syllabus

The Prelims has two papers, both with objective questions. Each paper has a time limit of two hours, and wrong answers carry negative marking of one-third.

Paper	Questions	Marks	Nature
GS Paper I	100	200	Counts for the cut-off
CSAT (Paper II)	80	200	Qualifying (33%)

GS Paper I Topics

General Studies Paper I tests awareness across seven areas.

• Current events: national and international events of importance.
• History: Indian history and the Indian national movement.
• Geography: Indian and world geography, including physical, social and economic aspects.
• Polity and governance: the Constitution, political system, Panchayati Raj, public policy and rights issues.
• Economy: economic and social development, sustainable development, poverty, inclusion and demographics.
• Environment: biodiversity, climate change and general issues that need no specialised subject knowledge.
• General science: everyday science and recent developments.

CSAT Paper II Topics

The CSAT tests comprehension, interpersonal and communication skills, logical reasoning, analytical ability, decision-making and problem-solving. It also includes general mental ability, basic numeracy up to the Class 10 level, and data interpretation. Because it is qualifying, aim for steady accuracy rather than a high score.

UPSC Mains Syllabus

The Mains has nine papers, and each paper is descriptive. Since answers are written in full, practice matters as much as reading.

• Paper A (Indian language, 300 marks): it is qualifying, and you need at least 25%.
• Paper B (English, 300 marks): it is also qualifying, with the same 25% limit.
• Essay (250 marks): you write two essays, one from each of two sections.
• GS Paper I (250 marks): it covers Indian heritage and culture, modern history, post-independence India, world history, society and geography.
• GS Paper II (250 marks): it covers governance, the Constitution, polity, social justice and international relations.
• GS Paper III (250 marks): it covers technology, the economy, agriculture, biodiversity, environment, security and disaster management.
• GS Paper IV (250 marks): it covers ethics, integrity and aptitude, and it includes case studies.
• Optional Paper I (250 marks) and Paper II (250 marks): these test your chosen subject.

The rank list uses the essay, four GS papers and two optional papers, which total 1750 marks. In contrast, the two language papers only qualify.

Optional Subject Selection

You pick one optional subject from a list of about 48, which includes 25 subjects and 23 literature papers. A good choice depends on three points. First, check your interest and background. Next, check how much of the syllabus overlaps with the GS papers. Finally, check the availability of good notes and answer-writing guidance. Since the optional carries 500 marks, avoid changing it after you start.

UPSC Interview (Personality Test)

The Interview carries 275 marks. A board tests your mental alertness, clarity, balance of judgement and leadership. It does not test your knowledge in an exam style. Instead, the board explores your background, your DAF (Detailed Application Form) and current affairs.

Eligibility Snapshot

To apply, you need a graduation degree from a recognised university. The age limit is 21 to 32 years for the general category, with relaxations for other categories. The number of attempts is six for the general category and nine for OBC. Meanwhile, SC and ST candidates have unlimited attempts up to the age limit of 37. Always confirm these details in the official notification, because rules can change.

How to Use the UPSC Syllabus Effectively

Print the syllabus and break each line into topics. Then map every topic to a source, such as an NCERT book, a standard text or a newspaper. Next, mark each topic as “Prelims”, “Mains” or “both”. Because many topics repeat across stages, this saves time. After that, review the previous years’ papers to see which sub-topics appear most.

A Simple Weekly Plan

• Mon–Fri: read one static subject and one current-affairs topic each day.
• Saturday: write two Mains answers and review them against the syllabus.
• Sunday: revise the week and take a short test.

For general study habits, read how to stop procrastinating. For a roadmap after school, see the section on exam preparation.

Subject-Wise Sources for the UPSC Syllabus

A syllabus lists topics, but it never names books. Therefore, build a source map early, and keep it short.

• History: start with NCERT books, because they give a clear base, and then add one standard text for modern India.
• Geography: read NCERT books for physical and human geography, and use an atlas for maps.
• Polity: read one standard polity book, and follow the Constitution’s articles through examples.
• Economy: begin with NCERT basics, and then follow the Economic Survey and the Union Budget summary.
• Environment: read the basic ecology chapters, and add current reports on climate and biodiversity.
• Science and technology: follow a newspaper for new developments, since questions are usually news-based.
• Ethics: read the syllabus carefully, because case studies reward clear and balanced reasoning.

How Prelims and Mains Overlap

Many topics appear in both stages. For example, polity and economy are tested as facts in Prelims and as analysis in Mains. As a result, one reading can serve both stages if you take notes in an answer-friendly way. First, learn the facts. Next, add two or three points of analysis for each topic. Finally, practise writing a short answer from your notes.

Where Current Affairs Fits

Current affairs run through almost every paper. Prelims asks about recent events directly, while Mains expects you to use examples and data. Because of this, read one good newspaper daily, and make short notes under the syllabus headings instead of dates.

Common Mistakes with the UPSC Syllabus

• Aspirants collect too many books, so they never finish any.
• Many ignore CSAT, but a score below 33% ends the attempt.
• Some skip the Ethics paper, although it is high-scoring when you practise case studies.
• Because the syllabus is only a list of headings, students often read beyond the demand of the question.

Make the Syllabus Work for You

The UPSC syllabus rewards a steady plan more than long hours. Turn each heading into a topic list, link it to one reliable source, and test yourself every week. Then continue with the UPSC Notes category, or go back to the The Note homepage.