Most messengers begin by asking for your phone number. It’s how they find your friends for you, and it’s also a detail that follows you around: the same number is in other people’s address books, on your business card and with your carrier. If you’d rather not hand it over, your options fall into two groups: apps that hide your number, and apps that never ask for one.
The short answer
Threema and Session are messengers you can use with no phone number at all, and Krypton Ø (Krypton zero) is an invite-only social network that asks for neither a number nor an email. Signal and Telegram both still need a number to sign up. What they’ve added are ways to keep it out of sight.
If you only want to stop the people you chat with from seeing your number, Signal’s or Telegram’s settings are enough. If you don’t want a service to hold your number at all, choose one that doesn’t ask.
Hiding a number isn’t the same as not having one
When an app hides your number, the service still has it. It’s on file, and it’s what the account depends on. When an app never asks, there’s nothing on file to show, leak or be asked for. The table shows where each app stands.
| Signal | Telegram | Threema | Session | Krypton Ø | |
|---|---|---|---|---|---|
| Phone number to sign up | Yes | Yes (your own, or an anonymous number bought on Fragment) | No (linking one is optional) | No | No |
| How people reach you | Your number, or a username you share | Your number, or a public username | A Threema ID | An Account ID | A Fam request, QR code or Fam link |
| What the account depends on | Your phone number | Your phone number | Your Threema ID and Threema Safe password | A recovery password | 18 words on paper and a six-digit PIN |
| What it is | Messenger | Messenger with large groups and public channels | Messenger | Messenger | Social network with posts and chats |
| Who can join | Anyone | Anyone | Anyone | Anyone | Only through a member who knows you |
Krypton Ø is our own app, so read that column knowing who wrote it.
Apps that hide your number
Signal
You can’t sign up for Signal without a phone number. What changed in February 2024 is how visible it is. Your number is now hidden by default from anyone who doesn’t already have it saved, and you can create a username to give out instead. A Signal username isn’t a login or a public handle, and it isn’t shown on your profile. It’s only a way to start a chat without handing over your number. You can also choose who’s allowed to find you by number.
Signal keeps very little alongside that number. It says the only information it can provide in response to a legal request is when an account was created and the date it last connected.
Telegram
A Telegram account has to be connected to a mobile number. By default the number is visible only to people you’ve saved as contacts, and a username lets anyone else reach you without it. Since December 2022 you can also sign up with an anonymous number bought on the Fragment platform instead of a SIM card, which is as close as Telegram gets to an account without a personal number.
Two things are worth knowing before you rely on that. Telegram’s ordinary chats aren’t end-to-end encrypted, only its secret chats are, as covered in Signal vs Telegram: which one is actually private?. And its privacy policy says it may disclose a user’s IP address and phone number when it receives a valid order from judicial authorities.
Apps that never ask
Threema
Threema says it “can be used without providing any personal information whatsoever.” The app gives you a Threema ID, and linking a phone number or email to it is optional. Everything is end-to-end encrypted, including group chats and calls, and group calls hold up to 16 people. It’s a one-time purchase with no subscription.
The backup is called Threema Safe. To restore an ID you need the ID itself and your Threema Safe password, and if you forget the password, the backup can’t be restored. It doesn’t include your chats or media.
Session
Session needs no phone number or email either. You get an Account ID, and messages travel through an onion-routing network so that, as Session puts it, “a server which receives a message never knows the IP address of the sender.” Group chats are end-to-end encrypted and hold up to 100 people. Voice and video calls are in beta and off by default.
Your way back into an account is its recovery password, a set of words you need to keep somewhere safe.
Krypton Ø
Krypton Ø isn’t only a messenger. It’s an invite-only, end-to-end encrypted social network for adults who want to share posts, photos and chats only with people they actually know. You join with keys made on your phone. It never asks for a phone number or an email, and it never uploads your contacts.
Because there’s no number to look you up by, you connect with someone by sending a Fam request, scanning each other’s QR code or sending a Fam link that works once within 24 hours. Fam is what Krypton Ø calls the people you’re connected with. If you lose your phone, 18 words you wrote on paper and a six-digit PIN bring the account back on a new one, after a 48-hour wait that your old phone can cancel.
What you take on when there’s no number
You find people yourself. A phone number is what lets an app match you against other people’s address books. Without it, you exchange an ID, a QR code or a link. That takes a minute longer, and it also means nobody finds you just because they have your number.
Recovery is your job. There’s no carrier and no text message to fall back on. Threema needs your ID and Threema Safe password, Session needs its recovery password, and Krypton Ø needs your 18 words and PIN. Write them down and keep them somewhere you’ll still have if the phone is gone.
No number doesn’t mean anonymous. A server can still see the IP address a request comes from. Session is built to hide that with onion routing. Krypton Ø says plainly that its server sees an IP address and a time at the moment a request arrives. If hiding where you connect from matters to you, check what each service says about it.
Where Krypton Ø fits, honestly
If what you need is a messenger without a phone number, Threema and Session are built for exactly that, and anyone can join them. Krypton Ø covers a narrower case: a closed place for posts, photos, chats and calls among people who already know each other. It’s new and small, it’s on Google Play for Android now with the iPhone app in App Store review, it’s for adults only (18 and over), and you can only join through someone who’s already a member. The reasons it’s closed are in Why Krypton Ø has no open sign-up.
What it costs
Posts, replies, chats and every safety feature in Krypton Ø are free. KryptonØ+ adds voice calls with your Fam, up to 10 photos or videos per post, 5-minute videos, larger files and bigger chats. It’s $49.99 a year or $199 once on the web, or $56.99 a year or $229 once in the app. See KryptonØ+.
FAQ
Can I use Signal without a phone number?
No. Signal needs a phone number to sign up. What you can do is keep it out of sight: it’s hidden by default from people who don’t already have it, and you can share a username instead.
Can I use Telegram without a phone number?
Not without any number. A Telegram account has to be connected to a mobile number, either your own or an anonymous number bought on the Fragment platform. A username lets people contact you without seeing it.
Which messengers need no phone number at all?
Threema and Session. Both are end-to-end encrypted messengers that give you an ID in place of a number. Krypton Ø also needs no phone number or email, but it’s an invite-only social network, not an open messenger.
What happens if I lose my phone and there’s no number on the account?
You restore the account with what you saved when you set it up: your Threema ID and Threema Safe password, Session’s recovery password, or Krypton Ø’s 18 words and six-digit PIN. Keep them safe. With Threema, a forgotten Threema Safe password means the backup can’t be restored, and Krypton Ø’s server can’t open your recovery backup without the 18 words.
Is a messenger without a phone number anonymous?
Not automatically. It means the service doesn’t hold your number, but a server can still see the IP address you connect from. Session routes messages through an onion network to hide it. Krypton Ø’s server sees an IP address and a time when a request arrives.