Tagging a user in a Bluesky post is a direct way to mention someone or start a conversation. Many users try typing the full handle from memory, which often fails due to typos or incorrect format. The platform provides a built-in autocomplete feature that ensures the tag is accurate and works every time. This article explains the correct method to tag any user, including those with custom domains, and covers common mistakes that break mentions.
Key Takeaways: How to Tag Users on Bluesky
- Type @ then the username in the compose box: Triggers the autocomplete dropdown with matching accounts.
- Select the correct user from the dropdown list: Inserts the full handle including the domain, preventing broken mentions.
- Do not manually type the full handle: Manual typing often misses the domain or includes typos that break the tag.
How Bluesky User Mentions Work
Bluesky uses the AT Protocol, which requires a complete decentralized identifier for each user. A standard handle looks like @username.bsky.social. Users with custom domains have handles such as @example.com. When you type a mention, the platform must resolve the full handle to the user’s DID, a permanent identifier. The autocomplete feature performs this resolution automatically. If you type the handle manually and make a single mistake, the mention becomes plain text and the user receives no notification.
Prerequisites for tagging include having a stable internet connection and a working Bluesky account. The feature works identically on the Bluesky web app, the official mobile app for iOS, and the official mobile app for Android. No special permissions or settings are required.
Steps to Tag a User in a Bluesky Post
Follow these steps to ensure your mention reaches the intended user.
- Open the compose box
Click the new post button in the web interface or tap the compose icon in the mobile app. The compose box is a text field where you write your post content. - Type the @ symbol followed by the username
Position your cursor where you want the mention to appear. Type @ and then start typing the username of the person you want to tag. Do not add a space before the @ symbol. - Select the correct user from the dropdown
A dropdown list appears below the text field, showing matching accounts. The list displays the display name and the full handle. Tap or click the correct entry. The handle is inserted automatically with the complete domain. - Complete and post
Finish writing your post. The mentioned user appears highlighted in the post. When you send the post, the user receives a notification and the mention becomes a clickable link to their profile.
Common Mistakes That Break User Tags
Manually typing the full handle
Manually typing @username.bsky.social or @customdomain.com often introduces errors. A missing dot, an extra character, or a wrong domain makes the mention fail. The autocomplete dropdown is the only reliable method. If you must type manually, copy the handle directly from the user’s profile page and paste it into your post.
Adding a space before the @ symbol
A space before the @ symbol breaks the mention. For example, writing Hello @username works, but Hello @ username or Hello@username does not trigger the autocomplete. Keep the @ symbol directly attached to the username without any preceding or following spaces.
Using the wrong domain for custom handles
Users with custom domain handles do not have .bsky.social in their handle. If you type @example.com.bsky.social, the mention fails. Always use the autocomplete feature to get the exact handle format. The dropdown shows the correct domain automatically.
Tagging a user who has blocked you
If a user has blocked your account, you can still type their @handle in a post. However, the mention will not create a clickable link and the blocked user will not receive a notification. The autocomplete dropdown will not show blocked users. There is no workaround for this limitation.
Bluesky Standard Handle vs Custom Domain Handle
| Item | Standard Handle | Custom Domain Handle |
|---|---|---|
| Format | @username.bsky.social | @example.com |
| Autocomplete behavior | Works the same | Works the same |
| Manual typing risk | High chance of typos in the domain | High chance of typos in the domain |
| Notification delivery | Delivered if handle is correct | Delivered if handle is correct |
| Profile link in post | Clickable if handle is correct | Clickable if handle is correct |
You can now tag any user in a Bluesky post using the autocomplete dropdown method. This approach eliminates typos and ensures the mention links to the correct profile. For users with custom domain handles, always rely on the dropdown rather than manual entry. As an advanced tip, you can tag up to 100 users in a single post, but notifications are still sent individually to each mentioned user.