Twilio registration for A2P 10DLC is now available for all customers. Please be aware as you register that there are still limitations as Twilio rolls out A2P 10DLC. These limitations are being removed over time, and this article is being updated accordingly as the situation changes.
Most importantly, please note that completing US A2P registration during the current stage does not instantly transition your message traffic to T-Mobile's A2P 10DLC connection. Once you complete registration, your traffic toward AT&T will immediately begin going over the registered route toward AT&T. Your traffic toward T-Mobile (including Sprint) will be moved to the T-Mobile registered route as soon as Twilio is able to do so.
There are also some limitations that uniquely affect ISV-type customers. Those are listed separately below. Read on for details.
- Registration limitations
- Carrier limitations
- Throughput limitations
- MMS limitations
- Limitations with sharing A2P Brand registration across multiple Twilio Account SIDs
- Limitations specific to ISV-type customers
- Other considerations
Registration limitations in A2P 10DLC
Subaccounts: It is not currently possible to create a Primary Business Profile on a subaccount. However, if you are a Direct customer and you complete registration of your Primary Business Profile and A2P Brand on your Twilio parent account, you can share it to your subaccounts. You can reach out to Support if you don't want this parent-to-subaccount profile sharing to take place. See Limitations with sharing A2P Brand registration across multiple Twilio Account SIDs below.
Carrier limitations in A2P 10DLC
Migration of T-Mobile traffic is currently paused, so for new registrations only AT&T traffic is currently being migrated. Once T-Mobile enablement resumes, customers who have successfully registered their traffic for A2P will have it migrated automatically.
If you are one of the few customers who have had their A2P traffic migrated on T-Mobile, please do not remove numbers from your approved Campaigns/Messaging Service as this can cause issues with your numbers/campaigns.
Throughput limitations in A2P 10DLC
As of July 12, the Trust Score you receive will dictate the throughput of your long code numbers toward AT&T. The final implementation of message sending throughput for all carriers, as outlined in Message throughput and Trust Scores, is still underway.
Messages toward Verizon and T-Mobile users continue to be handled as usual, with a sending rate of 1 MPS per Twilio +1 phone number. However, once your traffic is registered and moved to AT&T's A2P 10DLC route, your throughput toward AT&T mobile users will be dictated by your Trust Score.
MMS limitations in A2P 10DLC
Twilio MMS traffic is not currently sent over A2P 10DLC. Customers registered for A2P 10DLC will continue to have their MMS traffic to T-Mobile and AT&T sent using our standard long code routes. We are working with carriers to fully support MMS over A2P 10DLC at a later stage.
Limitations with sharing A2P Brand registration across multiple Twilio Account SIDs
Sharing from a primary Twilio Account SID to another primary account's subaccounts
If your business has multiple use cases spread out across multiple primary Twilio Account SIDs ("projects"), you can now request Twilio share your A2P Brand registration to another primary Twilio account. However, if the second primary Twilio account has subaccounts, you will not be able to share the (already-shared) Brand from that parent Account SID to those subaccounts.
This is an uncommon scenario, but if this applies to you, Twilio is working toward a solution, however there is no ETA. As of now, you can solve this by registering your A2P Brand again on any additional Primary Accounts that have subaccounts, and then share the Brand to those subaccounts.
Limitations specific to ISV-type customers
No phone number registration status for externally-registered Campaigns.
Twilio does not currently have the ability to retrieve number registration status for externally-registered Campaigns. If you are am ISV who registers Campaigns directly with TCR and associate those with Twilio numbers, we cannot currently confirm which of your Twilio numbers have been fully migrated to your A2P registration.
Short code numbers or Toll-Free numbers in your Messaging Service will not be affected by A2P 10DLC registration.
For customers who use Messaging Service number selection (passing a Messaging Service SID in your API requests instead of specific From numbers), any short code or Toll-Free numbers in your Messaging Service will continue to be prioritized over long code numbers unless a Sticky Sender mapping already exists. This is because of the higher MPS throughput from short codes and Toll-Free numbers – long code numbers continue to receive 1 MPS (see above).