Yes. Most of your data can be removed while the account stays exactly as it is, and the controls are more thorough than people expect.
Deleting messages and chats
- Tap a message, or press and hold to select several. To remove whole conversations, hold to select them in the chat list.
- Tap the delete icon.
- Tick the option to delete for both parties.
In a one-to-one chat this works for any message, including ones the other person sent, with no time limit, and it leaves no marker behind.
What else you can clear
- Synced contacts. Remove the contacts Telegram holds, under Privacy and Security.
- Cached media. Settings, Data and Storage, Storage Usage. Local copies go; the originals stay in the cloud.
- Active sessions. Terminate devices you no longer use.
- Payment and shipping details, if you have used Telegram's payment flow.
These live under Settings, Privacy and Security. On iOS there is one more step: Data Settings inside that screen.
Export first if you might want it
Settings, Advanced, Export Telegram Data produces a browsable archive of everything held. Running an export before a large clean-up costs nothing and is impossible to do afterwards.
Deleting removes data from Telegram. It cannot remove a copy the other person already saved or a screenshot they already took.
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