Dial `*123#` from your BSNL mobile
Dial `*124#` to check data balance on some BSNL plans
Use the BSNL Selfcare app
Log in to the BSNL website and check your account details
Send an SMS to BSNL customer care if your circle supports it
Call BSNL customer care at `1503` from your BSNL number
Check your data usage in your phone’s mobile data settings
Use the My BSNL app if available in your region