Blocking is built into the Phone and Messages apps: blocked numbers can't call or text you, and they get no notification of being blocked.
- 1From a call: Phone app → Recents → tap the number → Block/Report spam.
- 2Any number manually: Phone → menu (⋮) → Settings → Blocked numbers → Add a number.
- 3From a text: Messages → open the conversation → menu → Block & report spam.
- 4Unknown callers: Phone → Settings → Blocked numbers → toggle 'Unknown' to block hidden/private numbers.
- 5Unblock anytime in the same Blocked numbers list.
Tip: Enable Caller ID & spam protection in Phone → Settings for automatic flagging of likely spam calls before you answer.