When you register for JEE Advanced, then you will have to register using your JEE Main Application number. After registering for JEE Advanced, you will be allotted a unique application number (You can say this to be JEE Advanced Application number).

After the admit cards will be out, you will be required to use your JEE Advanced Roll No. for any references. If you forget your JEE Advanced Roll Number, then you will be able to get it using your JEE Main App. No. and your contact details.

So, you may assume that a separate application number is allotted for JEE Advanced but generally it is used at rare places (All the required processes are usually done by using your JEE Main Application No.).

For any counselling/ cutoffs related query, you may use the B.Tech companion through the link provided below:

https://www.careers360.com/btech-companion

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