How To Choose Civil Services IAS Mains Optional Subject : Detailed Guidelines, Full List, Comparative Analysis & Things to Avoid

Selecting the most scoring and vital UPSC IAS Mains Optional goes a long way in helping a student score well in Civil Services Mains Exam. The Civil Services Mains exam is designed to test the intellectual prowess of an aspirant. It is intended to assess the overall mental traits and depth of understanding of a particular candidate. This is why the most appropriate Civil Services IAS Mains Optional Subject needs to be selected before beginning preparation.

However, in the initial stages of preparation, it is challenging to make out which subject is interesting enough to sustain an aspirant’s attention for the next 1 or 2 years at a stretch. Many senior aspirants went through the same dilemma of choosing a ‘scoring’ or ‘manageable’ optional subject, for almost a month during the initial phase of their preparation.

Detailed Guidelines for Selecting Your Mains Optional Subject

  1. Divide your attention between the science and humanities subjects first up. Ask yourself which line of thought you are more ‘comfortable’ with. It does not matter which stream you graduated in, as long as you are convinced about your strengths and weaknesses in two separate fields. This is easy to decipher.
  2. Look at the list of optional subjects in UPSC CSE notification, and straightaway discard a few. There are 25 such subjects, excluding the regional languages, and you can easily make out which ones just don’t appeal to you.

    For some, such ‘straightaway rejects’ would be Botany, Engineering subjects, Management, Mathematics, Medical Science, Zoology, Statistics, Commerce and Economics. These should be the subjects in which you have ZERO interest.
  3. The list is already narrowed down, and you should not be left with more than 8 to 10 subjects after the first two steps. For the remaining subjects, check the following – Syllabus, Previous Years Question Papers, and availability of material for self-study.

    You don’t have to get into any kind of big data analysis. Still, a cursory glance at the keywords in the syllabus, and question papers will tell you whether you are feeling okay to go ahead with a particular subject.

    For example, most people don’t like reading maps at all, and they are pretty weak in identifying exact spots on a map – hence they should reject Geography even though it is not entirely out of their ambit of interest.
  4. You may still be unable to decide and be left with 2 or 3 options. In such a situation pick up the most basic book (ideally Class XI or XII NCERT) for each of the remaining subjects, and get through with it in 2–3 days each. You will yourself know the option that you will be going ahead with now.

Full List of Optional Subjects for Mains Exam

  • Agriculture
  • Animal Husbandry and Veterinary Science
  • Anthropology
  • Botany
  • Chemistry
  • Civil Engineering
  • Commerce and Accountancy
  • Economics
  • Electrical Engineering
  • Geography
  • Geology
  • History
  • Law
  • Management
  • Mathematics
  • Mechanical Engineering
  • Medical Science
  • Philosophy
  • Physics
  • Political Science and International Relations
  • Psychology
  • Public Administration
  • Sociology
  • Statistics
  • Zoology

Comparative Analysis of Science and Humanities Subjects

  • Science subjects – are often more scoring than humanities counterparts. But need way more time for completion of syllabus and revision. Besides, these subjects have no overlap with GS syllabus.
  • Humanities subjects – Difficult to score in, and vulnerable to ‘swings of scoring and marking by the UPSC. But needless time to complete, and knowledge of some subjects like PSIR, Sociology and Anthropology is beneficial in Essay, Ethics, Interview and GS.

Essential Points to Consider

  • Firstly, go through the complete list of all the mains Optional Subject. Invest your time in reading and understanding the syllabus.
    In case – if you do not want to opt for a particular subject you study during graduation or if that option is not a part of the official list, then go back to your school and college days. Think about your favourite subjects. Think about the optional subjects in which you can excel, in which subject you showed more interest and in the subject in which you scored the most.
  • Now contemplate on your current situation- how much you know about that particular subject and how much time you’ll need to prepare it. See which areas of news/articles you are more interested and talented in. Think about the topics – which you like- of General Studies. For instance- some people like history, some like polity, some sociology, so on and so forth. Think of shortlisting them as your Optional subject.
  • Now see the list of UPSC Optional again. Based on the above criteria, make a list of 4-5 subjects which captivates your interest.
  • Now go through the previous year’s question papers (at least of three years) of the shortlisted optional Subjects. Read all the questions papers thoroughly. Again gauge yourself as per the level of your interest or residual knowledge or skills you possess to answer each of those questions. It’s just to know the status of your current performance- and how comfortable you are with a subject. Don’t worry if you don’t know the answer to any question.
  • Analyze the syllabus and ponder over the fact that whether it will keep you interested throughout your preparation. This is important.
  • The availability of resources, materials and or guidance in the form of coaching or tuition matters a lot. For some of the subjects, it is difficult to get a standard book, for some coaching may not be available in your area. Non-technical questions can be prepared by doing self-study provided you regularly practice writing.
  • By now, candidates will have a clear picture of choosing the subject best suited to you. Your task is done.
  • Certain optional subjects are prevalent when it comes to Civil Services Mains.
  • Though the number of candidates/aspirants selecting each optional for IAS mains can vary year to year, the below table gives an average estimation for the coming years based on past year trends of optional subjects (As per latest syllabus).
  • Make sure to remember that all optional subjects are high scoring if you have knowledge in the subject and if you can answer the questions in an analytical frame of mind in line with the latest requirements of UPSC.

Things to Avoid While Choosing an Optional Subject

  • “My Friends and Family have suggested it.” – Never choose an optional because a friend or a family member suggested it.
  • “Most students opt for it.”-  Don’t opt for an optional just because-  it is what most of the candidates have chosen in the past as per the data. Believe it, or not – many serious candidates fall to this trick and waste attempts before they even realize it, and still many realize it after exhausting their efforts.
  • “It’s a high scoring IAS Mains optional”- Candidates have cleared this exam with almost every optional and not just with the so-called high scoring optional subject. In UPSC there is no high scoring- or a low scoring optional subject but only a paper, an innocent examinee and a ruthless examiner. High Scoring-Low scoring optional is a myth.
  • “The topper chose this subject last year”-  Never let your perception be the source of the guide. Don’t think previous toppers have chosen this subject so I will do the same, everyone has their interests, and probably they topped the examination because they did not base their choice of options on the selected subjects by still past toppers.


There is no such thing as the “best subject”. It’s a UPSC CSE myth. The thumb rule of choosing the optional subject for UPSC CSE, accepted by most successful and aspiring candidates, is that you must be interested in it. ALL the subjects have an equally good chance of fetching good marks. It depends on YOU how you handle that particular subject.

Areas covered in this article

  • How to select an Optional Mains Subject
  • 4 things to avoid while choosing an Optional Mains Subject
  • List of Optional Mains Subject

Related Links