Sender IDs

When you create a Verified SMS agent, you include the agent's sender IDs: long codes (E.164 format), short codes, national codes, or alphanumeric codes that can send SMS messages. Associating your agent with sender IDs lets Verified SMS and the Messages app know that they can expect messages from these IDs to be from your agent.

When the Messages app receives a message from an agent's sender ID, the app attempts to verify the message by hashing the message content and confirming the hash with Verified SMS. If the Messages app receives a message that isn't from an agent's sender ID, the app treats the message like it would any other SMS message and doesn't verify the message or display any branding in the conversation.

Unique and not shared

Make sure that sender IDs you associate with your agent are unique to your agent and are not shared with other brands or SMS aggregators in the countries that your sender IDs operate in.

When a user receives messages from a sender ID, all messages appear in the same conversation. If the user receives verified messages from your agent then receives a message from the same sender ID but from another SMS aggregator, that message appears as unverified in the conversation. Because the message from the other SMS aggregator wasn't stored as a hash from your agent, Verified SMS can't verify the message, marks the message unverified in the conversation, and removes some of your agent's branding on the user's device.


When you associate a sender ID with your agent, you include a list of countries that your sender ID operates in. For example, if the sender ID +12345 sends messages to users in the USA and Canada, you register it with the ISO 3166 Alpha-2 country codes US and CA.

If you send a message in a country that your sender ID isn't associated with (continuing the example, if you send a message from +12345 with the country code AU), the Messages app doesn't recognize +12345 as a sender ID from a Verified SMS agent and doesn't attempt to verify the message.

One conversation per sender ID

It's a best practice to send all of an agent's messages from a single sender ID. When an agent has multiple sender IDs, the Messages app verifies SMS messages from all of the IDs but keeps messages from each ID in their own conversations. For example, if Growing Tree Bank has the sender IDs 50470 and 88464, the Messages app verifies messages from both IDs but has one conversation with messages from 50470 and another conversation with messages from 88464.

Conversation with sender ID 50470 Conversation with sender ID 88464

Update sender IDs

To add, update, or remove sender IDs for an agent, contact us. Include the agent's information, the edits you want to make, and the affected sender IDs. If you want to add IDs, include the IDs' associated countries. After you submit the form, it can take up to three business days to update a agent's sender IDs.