I came to know about these "Don't call registeration pages" for various banks.

http://www.inuonline.com/dnc/donotcall.asp

http://www.online.citibank.co.in/portal/cbol/CLS02L06.htm

http://www.deutschebank.co.in/1078.html

https://play.standardchartered.com/smail/in/IN15/index.html

https://www.hdfcbank.com/applications/misc/dnc/dnc.htm

http://mail.abnamrobank.co.in/do_not_call_service_contact_from_home_1.asp