Dear Aspirant,

For fee waiver in NITs following are some of the conditions a student needed to comply with, the implementation might vary from NIT to NIT.

• STUDENTS BELONGING TO SC/STs COULD AVAIL 
  
• STUDENTS WHOSE FAMILY INCOME IS LESS THAN 1 LAKH PER ANNUM
• STUDENTS WHOSE FAMILY INCOME IS LESS THAN 5 LAKH AND ARE FROM RESERVED CATEGORY(2/3rd Waiver)

You must check the websites of respective NITs for more details.

NOTE: NITs also have a scholarship for students based on many criteria. You could also check them out.

Hope this helps.

Thank You.