The fastest way to block a caller depends on your phone type

On an iPhone, open the Phone app, find the number in your recent calls or voicemail, swipe left on it, and tap Block this Caller. The blocked number can still leave voicemails, but you won't see missed calls from them and their calls won't ring through. On Android, open the Phone app, press and hold the number, and select Block number — the exact wording varies by phone maker, but the option appears in the same menu. Both systems let you unblock numbers later if you change your mind.

If you don't have the number saved as a contact, you can still block it. On iPhone, go to Settings > Phone > Blocked Contacts and tap Add New to type in the number manually. On Android, open the Phone app, tap the three-dot menu, select Settings, then Blocked numbers, and add the number there. You don't need the caller's name or any other information — just the phone number itself.

Key Takeaways

  • iPhone users can block a caller by swiping left on their number in the Phone app and tapping Block this Caller.
  • Android users press and hold a number in the Phone app and select Block number from the menu.
  • Blocked callers can still leave voicemails, but their calls won't ring through and won't show in your missed calls list.
  • You can block a number you don't have saved as a contact by typing it manually into your phone's blocked list.
  • Most phones let you unblock numbers anytime through the same settings menu where you blocked them.

Blocking a number from a text message

If someone texts you instead of calling, you can block them from the Messages app without ever having their number in your contacts. On iPhone, open the conversation, tap the contact name or number at the top, scroll down, and select Block this Caller. On Android, open the conversation, tap the three-dot menu at the top right, and choose Block.

Blocking someone from a text message works the same way as blocking a call — they can still send you messages and make calls, but you won't receive them. The difference is that blocking from Messages is sometimes faster if you're already looking at their text, since you don't have to switch apps.

Using your phone's built-in spam filter

Both iPhone and Android have automatic spam detection that catches many unwanted calls before they reach you. On iPhone, go to Settings > Phone > Silence Unknown Callers to block calls from numbers not in your contacts. This sends unknown numbers straight to voicemail. On Android, open the Phone app, tap the three-dot menu, go to Settings > Spam and abuse, and turn on Filter spam calls. Google's spam filter learns over time and improves as more people report numbers.

The built-in filters catch a lot of robocalls and spam, but they're not perfect. Numbers that spoof local area codes or use real business numbers can sometimes slip through. If spam keeps getting past the filter, you may need to block individual numbers manually or consider a third-party app.

Third-party blocking apps for heavy spam

If you get dozens of spam calls a day, your phone's built-in tools may not be enough. Apps like TrueCaller, RoboKiller, and Nomorobo maintain larger databases of known spam numbers and can block calls before your phone even rings. Some of these apps are free with limited features, while others charge a monthly fee for advanced filtering.

Third-party apps work differently depending on which one you choose. TrueCaller shows you the caller's name and location before you answer, and blocks numbers from its spam database automatically. RoboKiller uses artificial intelligence to identify spam patterns and can answer robocalls with a fake voicemail to discourage future calls. Nomorobo focuses on blocking robocalls specifically and works on both cell phones and landlines.

Before installing a blocking app, check what permissions it asks for. Some apps request access to your contacts, call history, or location. Read the app's privacy policy to understand how it uses that information. Your phone's built-in spam filter usually handles most cases without needing a third-party app.

Blocking calls on a landline

If you have a traditional landline through your phone company, blocking options depend on your provider. Most major carriers offer a service called Call Block or Anonymous Call Rejection that you can set up by calling customer service or logging into your online account. These services typically cost $3 to $5 per month but block calls from numbers you add to a list.

Some landline providers let you block calls for free through their website. Verizon customers can use Call Filter, AT&T offers Call Protect, and CenturyLink has Anonymous Call Rejection. Check your phone bill or call your provider's customer service line to find out what blocking tools are available on your account and whether they cost extra.

What happens when you block someone

When you block a number on a cell phone, the blocked caller experiences a different outcome depending on when they try to reach you. If they call, the call goes straight to voicemail without your phone ringing. If they text, the message may or may not be delivered depending on your phone type — iPhone usually delivers the text but doesn't notify you, while Android behavior varies by phone maker. The blocked caller won't receive a message saying they've been blocked; the call or text straightforward doesn't go through as expected.

Blocked callers can still leave voicemails, and those voicemails go into a separate folder on most phones. On iPhone, blocked voicemails appear in a Blocked Messages tab in the Phone app. On Android, they typically go into your regular voicemail but may be marked differently. You can listen to them anytime, but you won't be notified when they arrive.

Unblocking a number if you change your mind

If you block someone by mistake or want to hear from them again, unblocking takes just a few taps. On iPhone, go to Settings > Phone > Blocked Contacts, swipe left on the number, and tap Unblock. On Android, open the Phone app, tap the three-dot menu, go to Settings > Blocked numbers, find the number, and tap the minus sign or delete option next to it.

Once you unblock a number, that person's calls and texts will come through normally again. You'll see their calls in your recent calls list and receive notifications for their messages. There's no record left that you had blocked them — it's as if the block never happened.

Frequently Asked Questions

Can a blocked caller tell they've been blocked?

No. A blocked caller won't receive any notification that you've blocked them. Their calls go to voicemail and they may assume you're unavailable. They might notice a pattern if all their calls go unanswered, but the phone system doesn't tell them they're blocked.

Will a blocked caller's text messages still come through?

On iPhone, text messages from blocked numbers are usually delivered but you won't see them — they go to a separate folder. On Android, behavior varies by phone maker, but most phones either deliver the text silently or don't deliver it at all. Either way, you won't be notified.

Can I block calls from a specific area code?

Your phone's built-in tools don't have an area code filter, but some third-party apps like TrueCaller and RoboKiller let you block entire area codes or number patterns. Check your app's settings to see if this feature is available. Your phone company may also offer pattern-based blocking for an additional fee.

What's the difference between blocking and Do Not Disturb?

Do Not Disturb silences notifications from all calls and texts but doesn't block anyone — calls still ring through if you allow repeated calls from the same number. Blocking actually prevents calls and texts from reaching you at all. Use Do Not Disturb for temporary quiet time and blocking for numbers you don't want to hear from.

If I block someone, will they see my calls if they try to call me back?

No. Blocking is one-way — you block their incoming calls and texts, but it doesn't affect their ability to call you. If they call you, it goes to voicemail. However, if you call them, your call goes through normally because you haven't blocked yourself on their phone.