Dial `*123#` from your BSNL mobile
Check the BSNL Selfcare app
Log in to the BSNL website and view your account details
Send an SMS with `BAL` to `123`
Call BSNL customer care at `1503`
Check the validity details in the recharge confirmation SMS
Use USSD codes shown by BSNL for your circle if `*123#` does not work