Essential study materials for UPSC IAS preparation include comprehensive study guides, NCERT textbooks, and current affairs resources. Core texts covering subjects like polity, geography, and economics are foundational. Aspirants benefit from reference books tailored to specific topics and mock test series to evaluate progress. Online platforms offering video lectures and interactive quizzes enhance understanding. Regularly updated materials for current events, along with magazines and journals, keep candidates informed on relevant issues. A well-rounded collection of resources is crucial for effective preparation and exam success.