Open the Phone app
Tap the menu or More options
Go to Settings
Tap Blocked numbers or Blocked contacts
View the list of blocked numbers
On iPhone, go to Settings
Tap Phone
Tap Blocked Contacts
View the blocked list
On Android, open the Phone app
Tap Settings
Tap Blocked numbers
View the blocked list
On some devices, check Messages settings
On some devices, check Contacts settings
On some carriers, use the carrier app or website
On some third-party call blocker apps, open the app and check the block list