In addition to the wide use of SMS messaging for personal conversations (person-to-person, or P2P messaging), messaging by businesses (application-to-person, or A2P messaging) is exploding as one of the most widely used channels for business communication with customers. Common use cases include marketing, mass alerts, verifications, and notifications.
- What is an Alphanumeric Sender ID?
- Benefits of messaging with Alphanumeric Sender ID
- Which Countries Support Alphanumeric Sender IDs?
- Limitations of Alphanumeric Sender IDs
- Opt-In/Opt-Out Requirements
- Formatting Requirements
- How to use an Alphanumeric Sender ID
What is an Alphanumeric Sender ID?
Alphanumeric Sender ID allows you to send Twilio Programmable SMS messages to supported countries from a personalized sender ID (like a business or organization name), instead of your E.164 formatted Twilio Phone number.
The example below shows how an Alphanumeric Sender ID (AUTHMSG) would look in place of the standard number.
Benefits of messaging with Alphanumeric Sender ID
Higher message deliverability: In many countries, regulatory bodies are increasingly filtering illegitimate A2P SMS use cases to curb unwanted messaging. For every Alphanumeric Sender ID request, Twilio completes a rigorous due-diligence and registration process with the telecommunication carrier in that country. Once this process is completed, Twilio handles fluctuating telecom logic, regulations, and carrier-specific rules to ensure your A2P messages reach their destination.
Improved brand recognition: Because recipients see your name with every SMS sent, using a recognizable Alphanumeric Sender ID reinforces your branding.
Increased open rates: As cases of spam and fraud increase, being able to easily identify the sender is a key factor in whether recipients decide whether to open a message. If the sender is an international or unfamiliar number, the chance of the message being opened is next to none. With Alphanumeric Sender IDs, recipients immediately recognize the sender and know the message is legitimate. As a result, they are up to 80% more likely to open the message.
Alternative to numeric longcode A2P messaging:
Alphanumeric Sender IDs can help work around the common challenges to A2P messaging as a high throughput and low carrier filtering option. Please note, Alphanumeric Sender ID is not available in the US or Canada.
- In most supported countries, customers can instantly provision an Alphanumeric Sender ID. These Alphanumeric Sender IDs are known as “dynamic.”
- Some countries require registration, which means the customer has to provide information and sometimes additional documents, resulting in additional time before the Alphanumeric Sender ID can be used. These Alphanumeric Sender IDs are known as “registered”
Which Countries Support Alphanumeric Sender IDs?
You can find out which countries support Alphanumeric Sender IDs on this page.
There is no additional charge for using an Alphanumeric Sender ID for most countries. However, for some countries that require registration there may be additional charges, such as one-time setup fees or recurring monthly fees. If so, that information is displayed in the Sender ID registration form of the relevant country.
Limitations of Alphanumeric Sender IDs
- Alphanumeric Sender IDs are only supported for paid Twilio accounts; not for free trial accounts.
- Alphanumeric Sender IDs are not supported in some countries and some supported countries require registration.
- Alphanumeric Sender IDs are only available for one-way outbound messages; recipients cannot reply directly to messages. (However, you can provide contact information in your message if you want recipients to respond).
- Some use cases are generally prohibited (e.g., gambling, dating sites, adult content, spam, phishing, and any content that violates the law or infringes on intellectual property).
- In some countries, additional use cases are prohibited, which are noted in the SMS Guidelines.
Users must specifically opt in to receive your messages and know how to opt out before you send your first message.
Note: End users cannot send replies like "STOP" to Alphanumeric Sender IDs. You must provide other instructions, such as writing a Support team, calling a Support phone line, or texting another phone number or code to allow users to opt out.
Please find the formatting requirements for Alphanumeric Sender IDs here.
Note: Some carriers may impose minimum length restrictions on Alphanumeric Sender IDs. This can result in your Alphanumeric Sender ID being modified or replaced by a generic sender ID, i.e. "unknown".
How to use an Alphanumeric Sender ID
First, use this page to make sure Alphanumeric Sender IDs are supported for a particular country and to check whether registration is required.
Whether you can use a dynamic Alphanumeric Sender ID or need to register the Alphanumeric Sender ID, you must first validate that the feature is enabled in your account. To do so:
- Access the Programmable Messaging page in Console.
- Click Settings.
From the General SMS Settings page, Verify that “Alphanumeric Sender ID” is set to Enabled.
To use a dynamic Alphanumeric Sender ID
If registration is not required, you can instantly use an Alphanumeric Sender ID.
Simply add the Alphanumeric Sender ID you want in the From parameter in line 4 of the cURL script, as shown in the example below:
curl -XPOST https://api.twilio.com/2010-04-01/Accounts/ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Messages.json \ -d "Body=Hello from my phone number" \ -d "To=+12685551234" \ -d "From=MyBusiness" \ -u 'ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:your_auth_token'
For details, see Sending Messages: Use an Alphanumeric Sender ID.
To register an Alphanumeric Sender ID
See this article for a guide on registering Alphanumeric Sender IDs: https://support.twilio.com/hc/en-us/articles/20153208099611-How-to-Register-an-Alphanumeric-Sender-ID
Using your registered Alphanumeric Sender ID
When our Sender ID team has informed you that the registration process is complete, you can use your registered Alphanumeric Sender ID by continuing to pass your Twilio number as the 'from' parameter in your API request and Twilio will dynamically replace the sender ID.