To block a Twitter user on the web:
Go to the profile page of the person you wish to block.
Click or tap the gear icon on their profile page. This brings up a drop-down actions menu.
Select Block or Report from the options listed.
Click Block to confirm.
To block a Twitter user on iOS:
Blocking from a Tweet:
Tap a Tweet from the user you’d like to block.
Tap the More icon (•••).
Tap Block or Report and then Block to confirm.
Blocking from a profile:
Visit the profile page of the user you wish to block.
Tap the gear icon
Tap Block or Report and then Block to confirm.
To block a Twitter user on Twitter for Android:
Blocking from a Tweet:
Tap the overflow icon
Tap Block or Report and then Block to confirm.
Blocking from a profile:
Visit the profile page of the user you wish to block.
Tap the gear icon
Tap Block or Report and then Block to confirm.