Basic Statistical Return Code or BSR Code is given by the RBI to all registered banks in India. BSR Code is a 7 digit number. And it is used in challan while depositing TDS or TCS to the Income Tax Department.  

BSR codes help the Income Tax Department to receive and gather information and records of taxes that are paid through the different banks by Payer/ Deductor. 

It is mandatory while filing e-TDS Return. You can find the same in Challan generated after a deposit of TDS/TCS on TIN NSDL.