The fastest way depends on your phone type

On most phones, you can block a number right from the call log without opening any settings. When a call comes in or you see it in your recent calls, look for a menu icon (three dots or lines) next to the number, then select "Block" or "Block this caller." The exact wording and location vary by phone model and operating system, but the principle is the same: find the number, tap the menu, choose block.

If you want to block a number before it calls you, or if you need to block multiple numbers at once, you'll use your phone's built-in blocking settings instead. These are usually found in the Phone app itself, not in your general Settings menu — though some phones also let you manage blocks from Settings.

Once you block a number, that caller won't reach you by phone call. Text messages from blocked numbers may still arrive (depending on your phone), and they won't know they've been blocked — the call will simply fail on their end. You can unblock a number the same way you blocked it.

Key Takeaways

  • The quickest block happens in your call log: find the number, tap the menu icon, and select block.
  • Your phone's built-in blocking feature is free and doesn't require an app or subscription.
  • Blocked callers won't know they're blocked, and their calls won't reach you or leave voicemail.
  • Text messages from blocked numbers may still arrive, depending on whether your phone separates call blocking from message blocking.
  • You can unblock a number at any time through the same menu where you blocked it.

Blocking a number on Android phones

Open the Phone app and go to your call log (usually labeled "Recents" or "Call History"). Find the number you want to block, press and hold it, and a menu will appear. Select "Block number" or "Block this caller." Some Android phones also show a block icon directly on the call log entry — tap that instead.

If you want to block a number you haven't called yet, open the Phone app, tap the menu icon (three dots), and look for "Settings" or "Blocked numbers." Tap "Add a number" and type in the number you want to block. You can also block an entire contact by opening your Contacts app, selecting the contact, tapping the menu icon, and choosing "Block."

To see your full list of blocked numbers, go to Phone app settings and look for "Blocked numbers" or "Blocked contacts." From there you can unblock anyone by tapping the X or delete icon next to their name.

Blocking a number on iPhones

Open the Phone app and go to Recents. Find the number you want to block, swipe left on it (or tap the info icon on the right), and select "Block this Caller." On newer iPhones, you may see a block icon appear when you swipe — tap that directly.

You can also block a number from your Contacts app. Open Contacts, find the person, tap "Edit," scroll to the bottom, and select "Block this Caller." If you want to block a number that isn't in your contacts, open the Phone app, tap the keypad icon, type the number, and tap the info icon (circle with an i) at the top right, then scroll down and select "Block this Caller."

To see or manage your blocked list, go to Settings, tap Phone, and select "Blocked Contacts." From there you can tap "Edit" and remove anyone from the blocked list by tapping the red minus icon.

What happens when you block a number

When you block a caller, their calls go straight to voicemail — but they won't actually reach your voicemail inbox. Instead, they'll hear a message saying the call couldn't go through, or the call will simply fail. They won't receive a notification that they've been blocked. From your perspective, you won't see missed calls from that number, and your phone won't ring or vibrate when they call.

Text messages are handled differently depending on your phone. On iPhones, blocked contacts can still send you text messages, but they'll go to a separate thread that you won't be notified about. On Android, it depends on your phone model and messaging app — some block texts automatically, others don't. If you want to block texts from someone, check your messaging app's settings for a separate blocking option.

Using Do Not Disturb or Focus modes instead

If you don't want to permanently block someone but need a break from their calls, your phone's Do Not Disturb (iPhone) or Focus (newer iPhones) and Do Not Disturb (Android) modes let you silence calls from everyone except people you choose. Open Settings, find Do Not Disturb or Focus, and turn it on. You can set it to allow calls only from your Favorites, Contacts, or specific people.

This is useful if you want to block calls during work hours, at night, or while you're in a meeting, without permanently blocking the person. You can also set these modes to turn on automatically at certain times. The blocked caller will hear a busy signal or be sent to voicemail, just like with permanent blocking, but you can turn the mode off whenever you want.

When blocking isn't enough

If you're receiving calls from numbers that keep changing, or if blocking individual numbers isn't stopping the calls, your phone's built-in tools have limits. Some phones let you block calls from unknown numbers entirely — on iPhones, go to Settings > Phone > Silence Unknown Callers; on Android, open the Phone app settings and look for "Block unknown" or "Filter unknown calls."

If you're dealing with spam or robocalls, your phone carrier may offer free spam-filtering tools. Contact your carrier directly to ask whether they have a call-filtering service you can turn on. Some carriers include this by default; others require you to opt in. Third-party apps like TrueCaller, RoboKiller, or Nomorobo can also filter calls, though these require installation and some charge a fee.

Unblocking a number if you change your mind

You can unblock someone at any time. On iPhones, go to Settings > Phone > Blocked Contacts, tap "Edit," and tap the red minus icon next to the name you want to unblock. On Android, open the Phone app, go to Settings > Blocked numbers, find the number, and tap the X or trash icon next to it.

Once unblocked, that person can call you normally again, and you'll see their calls in your recent list. They won't be notified that you've unblocked them — it's a silent change on your end.

Frequently Asked Questions

Will a blocked caller know they're blocked?

No. They'll hear a busy signal, a message that the call couldn't go through, or be sent to voicemail, but they won't receive a notification saying you've blocked them. Some people may figure it out after repeated failed calls, but the phone itself doesn't tell them.

Can I block text messages separately from calls?

On iPhones, blocking a contact blocks calls but not texts — texts from blocked people still arrive but go to a separate thread. On Android, it depends on your phone and messaging app. Check your messaging app's settings (usually under "Settings" or "Advanced") for a separate blocking or filtering option.

What if I block someone by accident?

You can unblock them immediately. On iPhones, go to Settings > Phone > Blocked Contacts and tap "Edit," then the red minus icon. On Android, open Phone app settings, find Blocked numbers, and tap the X next to their name. Once unblocked, they can reach you normally again.

Can I block calls from unknown numbers?

Yes. On iPhones, go to Settings > Phone > Silence Unknown Callers. On Android, open the Phone app, go to Settings, and look for "Block unknown" or "Filter unknown calls." This silences calls from numbers not in your contacts, though they can still leave voicemail.

Do I need an app to block calls?

No. Your phone's built-in blocking feature is free and works without installing anything. Apps like TrueCaller or RoboKiller add extra filtering for spam, but they're optional and some charge a fee. Start with your phone's native blocking before considering an app.