Telegram needs permission from your device's operating system to read your contacts.
For Android:
Go to your phone's Settings.
Navigate to Apps (or Apps & notifications, App management, depending on your phone's model).
Find and tap on "Telegram".
Tap Permissions.
Ensure "Contacts" is set to "Allow" or is telegram number database enabled.
For iOS (iPhone/iPad):
Go to your iPhone's main Settings app (the gray gear icon).
Scroll down the list of apps and tap on "Telegram".
Toggle the switch next to "Contacts" to ON.
Check Your Telegram Contacts:
Once contact sync is enabled and permissions are granted, Telegram will automatically scan your phone's address book.
Any contact you have saved who is also on Telegram will typically appear in your Telegram contact list within a few moments.
Method 2: Adding a Contact by Phone Number (Manual)
If you have someone's phone number but they haven't appeared through sync, or you prefer to add them manually:
Initiate "New Contact" or "Add Contact":
On Android: Tap the blue circular icon with a pencil/message bubble in the bottom-right corner of the main chats screen. Then, tap the "Add Contact" icon (a person with a plus sign) in the bottom-left.
On iOS: Tap the "New Message" icon (a square with a pencil) in the top-right corner of the chats screen. Then, tap "New Contact".
On Desktop: Click the three horizontal lines (☰) in the top-left to open the menu, then select "Contacts", and then click the "Add Contact" button.