In 2017, the Telegram platform gave users the ability to change their account phone numbers. In this article, we talk about why this is necessary, how to do it, and what difficulties you may encounter.

1. Why is it important to keep your account on a current number?

If you do not have a SIM card with the phone number specified in your Telegram account settings, you risk losing access to this account.

First, the mobile operator can sell your phone number to a new subscriber. If this new subscriber tries to log in to Telegram using this phone number, one of two things will happen:

1. If your account is not protected by a cloud password, the new owner of the number will be able to log in to your account and see all of its contents (except for secret chats).
2. If your account is protected by a cloud password, the new owner of the number will not be able to log in to it, but will be able to reset it by clicking the “Forgot password?” button. The account will not be deleted immediately, but only after 7 days. At the moment the reset procedure begins, you will receive a corresponding notification from the Telegram service account: try not to miss it. In order to cancel the account reset, you will need to change its phone number.

Secondly, in some cases, Telegram may terminate all sessions of the account. In this case, you will not be able to log back into the account if you do not have access to the SIM card with its number: see our article “How to log in to your Telegram account if you don’t have access to your SIM card?”

Thirdly, Telegram can switch your account to email authorization at any time. The next time you try to log in to your account, the platform will not send the code to other sessions, but instead will prompt you to enter an email address and confirm it not only with the code sent to this address, but also with the code sent to the SIM card. It is impossible to refuse to enter an email, and you will not be able to confirm the entered address.

Please note: if you do not have access to the SIM card with the account number, then even official Telegram support will not be able to help you regain access to it. We talked about this in more detail in Section 7 of the article “What to do if Your Telegram Account is Stolen?”

2. How to change the number?

1. Log in to your account in the official mobile application. You won’t be able to change the account’s phone number from a PC, web applications, or unofficial clients.
2. Go to the “Settings” section.
3. On Android, simply click on the inscription with the current phone number. On iOS, click the “Change” button in the upper right corner of the screen, and then the inscription “Change number”.
4. Confirm your intention to change the phone number and enter the new number.
5. Receive a confirmation code for the new number (in the form of an SMS message or a phone call) and enter it in the application.
   

Please note:

1. You cannot change the phone number of an account that you are not logged into. Neither knowing the cloud password, nor access to your email to reset it, nor official Telegram support, nor anything else will help: you can only change the phone number from an active session.
2. To change the phone number, you do not need access to the old SIM card. The confirmation code is sent only to the new one.
   

A card about changing a phone number is available on the official website of the Telegram platform at the link https://bugs.telegram.org/c/58.

3. What can prevent you from changing your number?

1. Usually, you can only change your phone number from a session that was created at least 24 hours ago. If you have just logged into your account, you will most likely not be able to change your number.
2. If you specify a new phone number that already has another Telegram account, the app will notify you of this and will not allow you to set it. If the new number really belongs to you, you will first have to delete the account to which it currently corresponds. To do this, interrupt the process of changing the number and try to log in using the new phone number:
   • If you can get inside the account, delete it using my.telegram.org web page (it must be opened in a browser, not directly in the Telegram app). Or tell the previous owner that the number now belongs to you and offer to save their account by transferring it to another phone number.
   • If the app asks you to enter a cloud password, click the «Forgot password?» button and follow the app’s prompts.
3. If the application reports that the confirmation code has been sent to a new phone number, but the code does not arrive, use our advice from section #3 of the article “What to Do When Telegram Auth Code Doesn’t Arrive?”

4. What happens after changing the number?

Everything that was in your account before will remain safe and sound: chats, contacts, settings, everything. Nothing will change except the phone number.

But for other users, something may change. Those users who saved your account in their list of Telegram contacts will see your new phone number only if your privacy settings allow them to.

Let’s imagine that:

1. Your phone number is +79011111111. In the section “Settings › Privacy and Security › Phone number › Who can find me by number?” you allowed the user Peter to find your account by phone number.
2. Peter saved your number +79011111111 in the address book of his phone with the name “John” and enabled the “Sync contacts” option in the section “Settings › Privacy and Security”. Your account will appear in Peter’s contact list in his Telegram account. And when Peter opens your profile, he will see the name “John” and the number +79011111111.
3. After that, you change your phone number to +79022222222.
   

What will Peter see after that?

It depends on your privacy settings:

1. If before changing the number, your privacy settings (“Settings › Privacy and Security › Phone number › Who sees my phone number?”) allowed Peter to see your phone number, then after changing the number, he will see the new phone number +79022222222 in your profile.
2. If before changing the number, your privacy settings restricted Peter from seeing your number, then after changing the number, your profile will be displayed to Peter without a phone number.

In any case, the synchronization of your contact between Peter’s device and Peter’s Telegram account will stop: if Peter changes your name in the phone’s address book from “John” to “John neighbor”, then in his Telegram account the contact’s name will still remain “John”. This is explained by the fact that synchronization occurs precisely by phone number:

1. In the first case, the number +79011111111 will still be recorded for the contact “John neighbor” in Peter’s device, and the new number +79022222222 will be recorded in his Telegram contact “John”. Neither Peter’s device nor Peter’s Telegram application will have any reason to consider these two entries as the same contact.
2. In the second case, Peter now does not know the phone number of the Telegram contact “John” at all, because you have forbidden Peter to see it. Therefore, Peter’s device and Peter’s Telegram application will not be able to understand that his Telegram contact “John” is somehow connected with the contact “John neighbor” in the address book of his device.