### Scam and Impersonation Prevention Bad actors often attempt to hijack usernames belonging to popular channels, public figures, or businesses to run phishing schemes. Restricting the immediate transfer of usernames makes it much harder for scammers to coordinate rapid handovers or impersonate trusted entities. ### The Username Cooldown Period When you remove or change a username on an account, it does not immediately return to the public pool. Telegram applies a temporary lock to the released username. During this cooldown period, which can last for several days or weeks, no other account can claim the username. Telegram does not publicly disclose the exact duration of this cooldown to prevent exploiters from timing the release. Because of this delay, attempting to manually swap a username between two personal accounts often results in losing the username, as it remains locked or gets claimed by a bot once the cooldown expires. ## How Capitalization (Caps) Works on Telegram

Capitalization in Telegram usernames is designed for visual customization rather than identification. ### Case Insensitivity Telegram usernames do not distinguish between uppercase and lowercase letters for routing purposes. For example, the usernames `@TelegramUser`, `@telegramuser`, and `@TELEGRAMUSER` all point to the exact same account. If someone searches for your username or sends a message using any variation of capitalization, the system will route it to you. ### Preserving Visual Casing Although the system treats all casing variations as identical, Telegram allows you to choose how your username displays to other users. You can edit the capitalization of your username (for example, changing `@johndoe` to `@JohnDoe`) directly in your profile settings. Because you already own the username, updating the capitalization does not release the name or trigger the security cooldown. This feature is particularly useful for improving the readability of usernames that contain multiple words. ## Important Limits and Constraints on Telegram Usernames

When managing a Telegram username, you must adhere to several technical limitations and rules: * **Character Length:** Usernames must be at least five characters long and cannot exceed 32 characters. * **Allowed Characters:** You can only use letters (a-z), numbers (0-9), and underscores. Usernames cannot begin with a number or an underscore, and they cannot contain spaces or special symbols. * **Rate Limits:** If you change your username too many times in a short period, Telegram may temporarily block you from making further changes. This rate limit is a security measure to prevent automated abuse. * **Collectible Usernames:** Telegram supports buying, selling, and auctioning usernames through the decentralized platform Fragment. Usernames secured via Fragment are owned as digital assets and operate under different transfer rules than standard, free Telegram usernames. ## How to Safely Update Your Username If you want to change your username or adjust its capitalization, use the official Telegram app on your mobile device or desktop:

1. Open the Telegram app and access the **Settings** menu. 2. Select your profile or tap **Edit Profile**. 3. Tap on the **Username** field. 4. Enter your desired username or adjust the capitalization of your current username. 5. Save the changes. If you are attempting to transfer a username to a new account, be aware of the cooldown period. Do not release a valuable username expecting to claim it immediately on another device, as you may lose access to it during the lock period.