India: SMS Features & Restrictions

India is a very complex market and there are a number of different regulations and restrictions you must comply with in order to send SMS here.

Sender ID:

Alpha Sender ID

Pre-registration is mandatory before you can use a specific alpha Sender ID to send traffic to India. The alpha sender ID needs to be 6 letters long, and you will need to provide SMS examples (minimum 25k SMS per month).
Please submit your registration request at or                                                           

This SenderID will be used as often as possible but a major percentage of traffic will still be overwritten to ensure delivery: Due to recent regulation changes the alpha SenderID will be prefixed with 2 letters depending on which carrier was used to deliver the SMS to the final operator, or more commonly a random number; e.g. MD-XXXXXX (where XXXXXX is the registered SenderID)
You can find a full list of prefixes here: India Pre-registered SenderID Prefixes.

Any unregistered sender ID is overwritten with a local shortcode as required by Indian regulations, whether the destination number is registered on the NDNC list or not.

Note: SID is not supported for International customers but all restrictions still apply for non-transnational traffic.


Transactional content:

If you have transactional messages which are either user-generated or expected, you can register an Alpha SenderID to bypass the traffic filters and NDNC registry.


Unicode is supported

Other features/restrictions of note: 

NDNC registration:

Messages sent to numbers registered in the Indian NDNC (National Do Not Call registry) list will be blocked. You can check the destination number on the Telecom Regulatory Authority of India registry using the following search tool: (omit India International prefix 91)

If you need to deliver messages to these numbers then you will need to pre-register your SenderID here: or

Time Constraints:

We can only guarantee message delivery between 9am to 9pm India local time. Messages submitted after 9pm we will attempt to send, but due to local regulations, these messages will be queued until the morning and you will be charged for them as usual.

If you need to deliver messages outside of these hours then you will need to pre-register your SenderID or

Maximum Throughput:

Local regulations specify the limitations to the number of messages that can be sent to the same number:

  • More than 6 messages to the same destination number within an hour with the same sender or text may be blocked
  • Users may not be able to receive more than a total of 200 SMS per day across all incoming streams.

Political Reasons

Messages towards Jammu and Kashmir networks (example, 405/55 - Airtel J&K) will be blocked by the government due to political sensitivity.


Global SMS Features Overview (Outbound only)

Global SMS Numbers Features Overview


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