From 27th September 2011 you can only send SMS to people who are not in the National Do Not Call Registry (NDNC). According to TRAI data still the larger group of population didn't opt-in for DND.
You cannot send promotional SMS before 9:00 AM and after 9:00 PM, all promotional communication should happen only between 09:00 & 21:00 every day. This is for all consumers irrespective of the National Do Not Call Registry (NDNC) list.
The telemarketer shall use alpha-numeric identifier for sending commercial communication in the format having nine alpha numeric characters, first alpha numeric character being code of Access provider and the second alpha numeric character being code of service area, as provided under the direction dated 10th December, 2008 issued by TRAI. The third alpha numeric character will be dash(-) and the fourth being any single digit (1-7) with each digit indicating a specific category of SMS as per schedule-I of the regulations and last five characters being five digit unique identification code provided by respective Access Provider to the telemarketer e.g XY-5ZZ, where X stands for code allotted to Access provider, Y stands for service area, 5 indicates that this SMS belongs to consumer goods and automobiles category and ZZ indicates five digit unique identification code allotted to telemarketer by the Access Provider
If a consumer on NCPR list, files a complaint for receiving any SMS, it will be traced back to the registered company. After 6th complaint and a fine total of rupees 7 lakhs (for 6 complaints) the company will be blacklisted and cannot do this business for next 2 years.
So from 27th September 2011, all messages will be scrubbed and will be only delivered to numbers which are not present in the NCPR list. This means that even if you submit to DND numbers, they will be filtered at our end and SMSes will not be delivered on them.
Customers (landline and mobile) who do not want to receive commercial communications can dial or SMS to 1909 (toll free) and register in either of the two categories:
Fully Blocked Category- stoppage of all commercial Calls/SMS
Partially Blocked Category- stoppage of all commercial Calls/SMS except SMS from one of the opted preferences
For registering option using SMS, for 'fully blocked category', write "START 0" and send it to 1909. For 'partially blocked category', send SMS 'START' with one or multiple options from the list of seven categories.
There are at present 7 preferences to choose from- Banking/Insurance/Financial Products/Credit Cards-1, Real Estate-2, Education-3, Health-4, Consumer goods and automobiles-5, Communication/Broadcasting/Entertainment/IT, Tourism-7.
On successful registration, customer will receive an SMS confirming exercised options and a Unique Registration Number within 24 hrs. The registration will be effective within 7 days of placing the request with the service provider. The customers can check the status of their registration by clicking on trai website