Messaging Services is a free Twilio feature designed to make it easier to send messages at-scale, as well as across multiple countries. In short, a Messaging Service is a container for multiple Twilio message senders, with additional message sending intelligence features. If you want to learn how to set up a Messaging Service, please check out Getting started with Messaging Services for a full walkthrough.
If you created a Messaging Service already, for example as part of A2P 10DLC onboarding, and you need to add numbers, read on.
Adding numbers to a Messaging Service using Console
In Console, navigate to your list of Messaging Services, then click on the one you want to add numbers to. On the left-hand side, click the “Sender Pool” link for your Messaging Service, then click the “Add Senders” button on the right side of the page. If you want to add Twilio phone numbers, this option will be pre-selected in the dialog that appears. Click Continue.
On the following page, you can either select your Twilio phone numbers from a list, or use the “Bulk-add phone numbers” option to input a list of numbers on your account that you wish to add to the Messaging Service.
Adding numbers to a Messaging Service using the API
You can add senders programmatically via the Phone Numbers, Short Codes, and Alpha Sender IDs subresources on the Messaging Services API.