We support Bulk SMS. The API remains the same as sending a single SMS, as given here: How to send an SMS.
Send Bulk SMS With Static Content (refer here)
This API will send SMSes with the same content to the array of numbers specified in the To parameter. To send SMS through our API, you will need to make a HTTP POST request
Send Bulk SMS With Dynamic Content (refer here)
This API will send SMSes to different numbers with different message content for each number.
To send SMS through our API, you will need to make a HTTP POST request
To send bulk SMS, specify an array of "To" numbers instead of a single number. The API contract remains the same.
Sample PHP bulk SMS API code sample is present at Sample Bulk Code
Once the APIs are run, You will get a response
On success, the HTTP response status code will be 200
The Sid is the unique identifier of the SMS and it will be useful to log this for future debugging