Plivo Bulk SMS destination limits?

Question

I'm testing Plivo for sending bulk SMS. I'm using the .NET REST API to send the messages.

Plivo's documentation for bulk SMS indicates that you can just concatenate numbers with a delimiter. This works fine. Does anyone know how many numbers can be included or can you tell me how many you have successfully sent in one API request?

var plivo = new RestAPI("xxxxxxxxxxxxxxxxxxx", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");

var sendData = new Dictionary<string, string>
                   {
                       { "src", "0000000000" }, 
                       { "dst", "00000000000<00000000000<00000000000<00000000000<00000000000<HOW MANY MORE???" }, 
                       { "text", "test sms from plivo" }
                   };

IRestResponse<MessageResponse> resp = plivo.send_message(sendData);

I couldn't find this information.

Answer 1

According to Plivo support:

"There is no limit to the number of destination numbers you can add in the "dst"parameter of the outbound message API. However, the outgoing rate limit is 5 messages per second per account."

Regardless of this response, I'm sure there is still some theoretical limit. Based off the other information I've gathered, it's better to split the API calls up anyway using multiple Plivo number (sender id's). If you have a suitable number of long codes, you shouldn't have to worry about this limit.

Related information:

Long code SMS restrictions

How do I send 6000+ messages using a long code?

In other words, use multiple long codes and split up your destination numbers accordingly to send out in parallel.

Edit* Received another response that seems more accurate

"You can add upto 250 numbers per API request. That should be the ideal limit on the destination parameter."

Answer 2

For anyone wondering what the actual bulk-messaging limit is nowadays (2021), it is 1,000 numbers per API call.

Thankfully this is now clearly stated on Plivo's API Docs page in the Bulk Messaging section:

The Message API supports up to 1,000 unique destination numbers.