Compulsory Subjects for UPSC Exam 2026 cover all the essential topics that every aspirant must study to succeed in both the Prelims and Main stages of the Civil Services Examination. These subjects include General Studies, CSAT, Ethics, Governance, and the compulsory optional papers in Mains. 

Understanding the structure and weightage of these subjects is crucial for creating an effective preparation strategy. By focusing on these compulsory areas, candidates can prioritise high-scoring topics, plan their study schedule efficiently, and strengthen their foundation to maximise their chances of clearing the UPSC CSE 2026.

Compulsory Subjects for UPSC Exam 2026

The Civil Services Examination (CSE), conducted by the Union Public Service Commission (UPSC), is one of the most challenging exams in India. To guide your preparation, you must know the complete list of Compulsory Subjects for UPSC Exam 2026 for both the Preliminary and Main stages. 

Understanding the structure and the nature of these subjects is the first step toward success. The UPSC CSE consists of three successive stages: the Preliminary Examination (Prelims), the Main Examination (Mains), and the Personality Test (Interview). Candidates must clear all preceding stages to be eligible for the next.

How Many Compulsory Subjects for UPSC Exam 2026?

The UPSC exam has a fixed structure of compulsory papers, though the total number of subjects tested within those papers is extensive.

• UPSC Prelims: There are two compulsory papers.
• UPSC Mains: There are nine papers in total, all of which are compulsory to appear for. Of these nine, seven papers are counted for the final merit ranking, and two are qualifying language papers.

In essence, all papers in both the Prelims and Mains stages are compulsory for all candidates.

Compulsory Subjects for UPSC Prelims and Mains List

Compulsory subjects for UPSC Prelims and Main determine a candidate’s eligibility for the next stage. Whether preparing for Prelims or the Main exam, knowing these compulsory papers is essential for effective planning and high-scoring answer writing:

Compulsory Subjects for UPSC Prelims List

UPSC Prelims exam is the first stage and acts as a screening test. It comprises two objective-type papers, both of which are compulsory to attempt.

Paper I: General Studies (GS-I) – (Counted for Cut-Off)

General Studies Paper I is the most crucial paper in the Prelims, as the marks obtained here are considered for the cut-off to qualify for the Mains exam. The compulsory subjects under this paper include:

• Current Events: National and International importance.
• History of India: Ancient, Medieval, and Modern Indian History, including the Indian National Movement.
• Indian and World Geography: Physical, Social, and Economic Geography.
• Indian Polity and Governance: Constitution, Political System, Panchayati Raj, Public Policy, and Rights Issues.
• Economic and Social Development: Sustainable Development, Poverty, Inclusion, Demographics, and Social Sector Initiatives.
• Environmental Ecology, Biodiversity & Climate Change: General issues that do not require subject specialisation.
• General Science: Basic scientific concepts and developments.

Paper II: CSAT (Civil Services Aptitude Test) – (Qualifying Only)

The CSAT paper is compulsory but is of a qualifying nature, meaning its marks are not counted for the Prelims cut-off. Candidates must score a minimum of 33% (66 marks out of 200) to qualify for this paper. The compulsory subjects for UPSC Prelims CSAT include:

• Comprehension
• Interpersonal Skills (including communication skills)
• Logical Reasoning and Analytical Ability
• Decision-Making and Problem-Solving
• General Mental Ability
• Basic Numeracy (Class X level: numbers, relations, orders of magnitude)
• Data Interpretation (charts, graphs, tables)
• English Language Comprehension Skills (The marks for this section are often considered separately or are qualifying in nature).

Compulsory Subjects for UPSC Mains List

The Main Examination is descriptive and consists of nine papers. All papers are compulsory, but they are categorised into two types: Qualifying and Papers Counted for Merit.

Qualifying Compulsory Language Papers

These two papers are mandatory, and a candidate must score a minimum of 25% to pass. The marks, however, are not counted in the final merit ranking.

Compulsory Papers Counted for Merit (Total 7 Papers)

These seven papers carry a total of 1750 marks and determine your final ranking. All these papers are compulsory for UPSC Mains 2026 aspirants.

While the Optional Subject (Papers VI and VII) is a matter of choice for the candidate, the papers themselves are a compulsory component of the Mains structure and contribute 500 marks to the final merit list. This means an aspirant cannot skip the optional papers and must choose and prepare for a subject to appear for these papers.

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UPSC Preparation Strategy for Compulsory Subjects

To succeed in the Compulsory Subjects for UPSC Prelims and Mains, your preparation should be integrated and multifaceted. The General Studies subjects for Prelims have a significant overlap with the Mains syllabus, which is why integrated study is often the most effective approach.

1. Start with GS Basics: Build a strong foundation in core subjects like Indian Polity (Constitution), History, Geography, and Economy, which are common to both Prelims and Mains.
2. Master Current Affairs: Current events of national and international importance are a compulsory subject in Prelims GS-I and form the dynamic part of almost all GS papers in Mains.
3. Qualifying Papers: Do not ignore the compulsory qualifying papers (English and Indian Language) in Mains. Practice comprehension and essay writing to ensure you score the minimum 25% required.
4. CSAT Practice: Treat the CSAT paper (Prelims Paper II) with seriousness. Although qualifying, many candidates find it challenging. Regular practice of logical reasoning, basic numeracy, and comprehension is necessary to score the compulsory 33%.

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