Bsnl service provides unlimites sms STV's
But now we have unlimited message center numbers code
Where you get same facility as paid STV user,
This tricks is tested in many states like West Bengal, Bihar, Kolkata, and many more state of india.
How to Activate unlimited Free SMS in BSNL?
Sms center numbers code are:-
Special Note:-Your balance should be below than Rs-.50, and you should add 0091 before any number (Eg-00919789***)