The fastest way to block a number depends on your phone type
On an iPhone, open the Phone app, find the number in your recent calls or messages, tap the info icon (the small circle with an "i"), scroll down, and tap "Block this Caller." On Android, open the Phone app, long-press the number in your call history, and select "Block number." Both phones also let you block directly from a text message: swipe left on iPhone or long-press on Android, then choose block.
If you do not have the number saved as a contact, you can still block it. The steps are the same — the phone does not care whether you have a name attached. Once blocked, that number cannot call or text you, and you will not see notifications when they try.
Some carriers also offer blocking through their own apps or websites. Verizon has Call Filter, AT&T has Call Protect, and T-Mobile has Scam Shield. These tools often catch spam before it reaches your phone, but the built-in phone blocking works for any number you choose, regardless of carrier.
Key Takeaways
- iPhone users can block a number in three taps from the Phone app or Messages app by tapping the info icon and selecting "Block this Caller."
- Android users long-press a number in the Phone app and select "Block number" from the menu that appears.
- Blocked callers cannot reach you by phone or text, and you receive no notification when they try.
- Your carrier may offer additional spam-filtering apps like Verizon Call Filter or AT&T Call Protect that catch unwanted calls before they ring.
- Blocking a number is permanent until you manually unblock it in your phone's settings.
Where your blocked list lives and how to manage it
On iPhone, go to Settings, tap Phone, then Blocked Contacts. You will see every number you have blocked. To unblock someone, swipe left on their name and tap "Unblock." On Android, open the Phone app, tap the three-line menu, go to Settings, then Blocked Numbers. The process is the same — tap a number and select "Unblock."
Your blocked list is stored on your phone itself, not on your carrier's servers. This means if you switch phones, your blocked numbers do not automatically transfer. If you back up your phone to iCloud (iPhone) or Google Drive (Android), some blocking data may transfer, but it is not may provide. If you have a long list of numbers you want to keep blocking, write them down or take a screenshot before switching devices.
What happens when someone you blocked tries to reach you
When a blocked caller tries to phone you, the call goes straight to voicemail without your phone ringing. They hear a message saying the call cannot be completed. Text messages from blocked numbers are silently deleted — you do not see them, and the sender gets no delivery confirmation. From their perspective, it looks like your phone is off or you are not responding.
Blocked callers cannot tell whether you blocked them or straightforward did not answer. They have no way to know the difference. Some people try calling from a different number to get around a block, so if you keep getting calls from new numbers, blocking each one as it comes is your only option through the phone itself.
When blocking is not enough and you need carrier support
If you are getting dozens of calls a day from different numbers, or if the calls are threatening or harassing, blocking individual numbers becomes impractical. This is when your carrier's spam-filtering service becomes useful. Verizon Call Filter, AT&T Call Protect, and T-Mobile Scam Shield use databases of known spam and robocall numbers to block them before they reach your phone. Some versions are free; others cost a few dollars per month.
These services are not perfect — some spam still gets through, and occasionally legitimate calls get flagged as spam. But they reduce the volume significantly for most people. You can turn filtering on or off in the app settings, and you can report numbers as spam to help the service improve.
If you are being harassed or threatened, contact your local police and your carrier's customer service. Carriers can sometimes block entire ranges of numbers or investigate patterns of calls. Police can file a report that may lead to legal action if the harassment is severe enough.
Why blocking on your phone does not stop texts from email addresses or apps
Phone blocking only works for calls and texts sent through your phone number. If someone sends you a message through Facebook, WhatsApp, Instagram, or email, blocking their phone number does nothing. You have to block them separately in each app.
To block someone in Facebook Messenger, open the conversation, tap the person's name at the top, scroll down, and tap "Block." In WhatsApp, long-press the contact and tap "Block Contact." In Instagram, go to their profile, tap the three dots, and select "Block User." Gmail lets you block an email address by opening the message, clicking the three dots, and selecting "Block [sender]."
If someone is harassing you across multiple platforms, blocking them everywhere takes time, but it is the most complete approach. Some apps also have a "report" option in addition to blocking — using both tells the platform that the behavior is unwanted and helps them take action against repeat offenders.
The difference between blocking, silencing, and do-not-disturb
Blocking stops someone from reaching you at all. Silencing (or muting) a contact means their calls and texts still come through, but your phone does not ring or vibrate — you only see them if you check your phone. Do Not Disturb mode silences all calls and texts except from people you have marked as favorites.
If you want to ignore someone temporarily but not permanently, silencing is gentler than blocking. You can silence a contact on iPhone by opening their contact card, tapping "Hide Alerts," and on Android by long-pressing their name in your contacts and selecting "Mute notifications." You can unmute them just as easily if you change your mind.
Do Not Disturb is useful when you need quiet time but do not want to block anyone. On iPhone, swipe down from the top right to open Control Center and tap the moon icon. On Android, swipe down twice and tap "Do Not Disturb." You can set it to allow calls from favorites or repeat callers (people who call twice in three minutes), which catches emergencies while blocking spam.
Frequently Asked Questions
Can someone tell if I blocked them?
No. When you block someone, their calls go to voicemail and their texts disappear silently. They cannot tell whether you blocked them, ignored the call, or have your phone off. Some people try calling from a different number to test whether they are blocked, but the phone itself gives them no confirmation.
What if I blocked someone by mistake?
You can unblock them when ready. On iPhone, go to Settings > Phone > Blocked Contacts, swipe left on their name, and tap "Unblock." On Android, open the Phone app, tap the menu, go to Settings > Blocked Numbers, tap the number, and select "Unblock." They will be able to reach you again right away.
Do I need to pay for blocking?
Built-in phone blocking is free on both iPhone and Android. Carrier spam-filtering apps like Verizon Call Filter and AT&T Call Protect offer free versions with basic features, though some charge a few dollars per month for advanced filtering. You do not have to pay anything to block a single number.
If I block someone, can they still leave voicemail?
No. When you block a number, calls go straight to voicemail, but the blocked caller hears a message saying the call cannot be completed. They cannot leave a voicemail. If you want someone to be able to leave a message but not ring your phone, use the mute or silence feature instead of blocking.
Will blocking work if they call from a different number?
Yes, but only for that specific number. If someone calls from their home phone, you can block it. If they call from their work phone, you have to block that number separately. Blocking one number does not block the person — it blocks the phone line. For repeated harassment from multiple numbers, contact your carrier or local police.