Signal Usernames Are Here!
Keep your phone number private with Signal usernames
As end-to-end encrypted messaging apps go, Signal stands apart as the gold standard of security and privacy. Up until now, you have had to give someone your phone number to chat with them on Signal. Well that’s no more the case!
When, Why?
Signal has launched usernames in beta, and they will be rolling them out to all users in the coming weeks. The username will act as a replacement so that you won’t have to give your phone number to others to be able to communicate with them.
With this, Signal is closing one of the few loopholes that could allow hacker’s access to a victim’s messages — where hackers hijack the phone number at the phone carrier level used to register with Signal.
It's important to note that usernames are not permanent handles or profile names; they are solely used for initiating contact on Signal without divulging personal phone numbers. Additionally, you will still require a phone number to sign up to Signal, this is done for spam prevention purposes.
Your username is not stored in plaintext1, meaning that Signal cannot see the usernames of given accounts.
So, What’s New?
New default: Your phone number will no longer be visible to everyone in Signal
If you use Signal, your phone number will no longer be visible to everyone you chat with by default. People who have your number saved in their phone’s contacts will still see your phone number since they already know it.
This helps keep your phone number private in case you need to talk to a non-contact, or someone you don’t trust with your phone number.
Connect without sharing your phone number
If you don’t want to hand out your phone number to chat with someone on Signal, you can now create a unique username that you can use instead (you will still need a phone number to sign up for Signal). A username is a way to initiate contact on Signal without sharing your phone number.
Instead of giving out your phone number, you can now share a username. You can also generate a QR code or link that directs people to your username, letting them quickly connect with you on Signal!
Control who can find you on Signal by phone number
If you don’t want people to be able to find you by searching for your phone number on Signal, you can now enable a new, optional privacy setting. This means that unless people have your exact unique username, they won’t be able to start a conversation, or even know that you have a Signal account – even if they have your phone number.
Your profile name stays as you choose it. Your username isn't shown on your profile, and others can't see or find it unless you tell them. Basically, people need to know your specific username to chat with you on Signal, and there's no directory to search for usernames.
If you’d still like everyone to see your phone number, you can change the default by going to Settings > Privacy > Phone Number > Who can see my number.
Sign me Up!
To make a username, go to Settings > Profile. Your Signal username, unlike your profile name, needs to be unique and must end with two or more numbers. You can change your username whenever you want, and if you don't want one anymore, you can delete it.
Usernames in Signal are made to be flexible. You might create one for a conference or a group trip and then change it later. Simply go to your Profile Details page and click on your username to make any changes. When you change your username, your Signal contacts won't be notified because they can't see your username in 1-1 or group chats.
— That’s it! I hope you found this small post informative, stay safe!
Usernames in Signal are protected using a custom Ristretto 25519 hashing algorithm and zero-knowledge proofs. Signal can’t easily see or produce the username if given the phone number of a Signal account. Note that if provided with the plaintext of a username known to be in use, Signal can connect that username to the Signal account that the username is currently associated with. However, once a username has been changed or deleted, it can no longer be associated with a Signal account.Â