Steps
- Settings → Phone Number → Change Number;
- Enter the new number and the code you receive;
- Choose whether to notify contacts (All Contacts is recommended).
What moves with you
- Chat history, Saved Messages, cloud files and groups;
- Your username, channels and bots;
- Other signed-in devices pick up the new number automatically.
Caution
The old number no longer belongs to the account afterwards. If you own groups, consider transferring some to other admins to avoid a single point of failure.