Open the Phone app
Tap Recents, Contacts, or Favorites
Find the number you want to block
Tap the info icon next to the number
Scroll down and tap Block this Caller
Tap Block Contact to confirm
To block from Messages, open the conversation
Tap the contact name or number at the top
Tap Info
Tap Block this Caller
Tap Block Contact to confirm
To block from FaceTime, open the FaceTime app
Find the caller
Tap the info icon next to the number
Tap Block this Caller
Tap Block Contact to confirm
To manage blocked numbers, go to Settings
Tap Phone, Messages, or FaceTime
Tap Blocked Contacts
Add or remove numbers as needed