Hello Aspirant,

If you get admitted into the B.S. program at IIT Madras this year and this year happens to be your first JEE Advanced attempt, then yes, you will remain eligible to take JEE Advanced again next year if you satisfy the other eligibility norms laid down by the conducting authorities of the exam. The important thing is that the candidate gets two chances at JEE Advanced at the most, and these chances have to come within two successive years from the year when they first appeared for the test. Since you are trying for the first time, you have one chance remaining for the next year.

But once you are admitted into an IIT undergraduate course, you cannot sit for JEE Advanced again to get into the same course. But if you are interested in a different course or a double degree (such as B.Tech + M.Tech), you may want to look up the particular rules from the JEE Advanced official website or the IITs.