UPSC Mains medium options:

Candidates may write all GS papers, Essay, and Optional papers in:

• English
• Hindi
• Any of the 22 Eighth Schedule languages: Assamese, Bengali, Bodo, Dogri, Gujarati, Kannada, Kashmiri, Konkani, Maithili, Malayalam, Manipuri (Meitei), Marathi, Nepali, Odia, Punjabi, Sanskrit, Santali, Sindhi, Tamil, Telugu, Urdu, or Santhali

Key rules:

• The medium is declared in the Detailed Application Form (DAF)
• You must write all papers in the same language — you cannot write GS1 in English and GS2 in Hindi
• Exception: Paper A (Indian Language) must be written in the language you selected for Paper A (not your main medium). Paper B (English) must always be in English.
• If your Optional has a literature paper (e.g., Hindi Literature, Tamil Literature), that paper is written in that language regardless of your main medium

Interview medium: You may choose English, Hindi, or the same Eighth Schedule language as your Mains medium for the interview. Most candidates use English or Hindi in the interview.

Source: UPSC Civil Services Examination Rules (published annually in Gazette of India); UPSC CSE 2025 Notification, upsc.gov.in