A guide to SMS Sender IDs
When sending an SMS, you have a couple of different options as to what the customer sees on their device in the ‘From’ field.
This blog will give you all the information you need to know about configuring the ID that your messages come from.
The sender ID basics
Sender IDs can be numeric, alphabetic or a mix of both – alphanumeric.
There is a maximum limit of 11 characters – the same length as a UK mobile number.
Spaces and non GSM characters (like dashes and commas) cannot be used in the Sender ID.
Can I receive a reply to alphanumeric IDs?
Sadly not!
If you send from an alphanumeric ID, most smartphones will now show a message that says ‘Can’t reply to this shortcode’, or if you are able to send a reply, the message won’t deliver.
The only way to receive a reply to an SMS is for the message to originate from an actual mobile number or a Virtual Mobile Number, which you can purchase from us within your account.
If a message is sent from a Virtual Mobile Number (VMN), your customer can send a reply like they would to a normal text message. Any incoming SMS will then be received in your account and show in your inbox. You can even forward it on to your email address, or via an API to your own systems!
If you do ever receive a message from an alphanumeric ID and you’re able to reply, that will be because it’s actually an RCS message (Rich Communication Services). This is like SMS 2.0, and something we can speak to you about!
Registering your sender ID
To send SMS messages to UK mobile numbers you do not need to register your sender ID. Simply choose whether to send from a VMN, or enter your own alphanumeric ID into the Sender field when crafting your campaign.
For other countries, like the US, Canada and Australia, there are more restrictions, and registration needs to happen before you can send to these destinations from the UK.
If you’re planning on sending to destinations outside of the UK, just speak to us and we can advise if you need to register, and how to do so.
Restricted senders IDs
Every country has a list of Sender IDs that are not permitted by the network. If you try to send from any of these ID’s, your messages will be flagged by the networks. This is to help stop spoofing and phishing.
We’ve put some measures in place on our systems to ensure that these IDs can’t be used unless proof can be provided that the ID is legitimate.
If you are planning on sending messages from what might be a restricted sender ID, just speak to our team and we’ll be able to advise you on what happens next!
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