Basically, you don't have much authority to determine who can follow you on Twitter, unless your account status is private. While there's no official way to remove followers from your account, you can remove some users' access to your Twitter feed by first blocking the account, then unblocking it. This way, the follower can be removed from the list without being notified of the change.
Step
Method 1 of 2: Using a Mobile Device
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Step 1. Tap or select the Twitter app
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Step 2. Touch the “Me” tab
This tab is indicated by a human-shaped icon that appears in the lower-right corner of the screen.
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Step 3. Touch the “Followers” option
It's above the “Tweets”, “Media”, and “Likes” options, at the top of the screen.
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Step 4. Select the followers you want to block
Once selected, you will be taken to the follower's account page.
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Step 5. Touch the gear icon shown on the page
It's to the right of the user's profile photo.
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Step 6. Tap on “Block (account username)” option
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Step 7. Touch the “Block” option when prompted
After that, the follower is officially banned from your account.
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Step 8. Touch the red “Blocked” icon
It's in the upper-right corner of the screen.
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Step 9. Tap on the “Unblock” option shown in the pop-up menu
The ban for that user has been undone, but he or she is no longer following your account.
Method 2 of 2: Using Desktop Sites
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Step 1. Visit your Twitter page
If you're not logged into your account, you'll need to enter your Twitter registered email address (or mobile number/Twitter username) and password.
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Step 2. Click the “Followers” option
It's on the left side of your Twitter feed, just below your profile photo and background image on your profile page.
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Step 3. Click the gear icon labeled “More user options” on the user's profile page
It's to the left of the “Follow” (or “Following”) button in the user information box.
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Step 4. Click "Block (username)" on the displayed drop-down menu
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Step 5. Click "Block" again when prompted
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Step 6. Now, click on the “Blocked” button
This button is in the top right corner of the user's profile. Once clicked, the user is no longer blocked. However, it has been removed from your follower list.
Tips
- You can go to a specific user's profile page to block them in a number of ways, including by clicking or tapping the associated username when it appears in the Twitter feed, or by searching for their name in the Twitter search bar.
- Blocked users cannot contact you in any way on Twitter.