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

On most phones, you can block a caller right from your recent calls list without opening any settings. Find the number or contact name in your call history, tap and hold it (or right-click on some phones), and select "Block" or "Block this caller." The phone then sends future calls from that number straight to voicemail. You do not need to know the caller's name or do anything else — the block takes effect when ready.

If you want to block someone before they call, or if you need to block multiple numbers at once, you can go through your phone's settings instead. Both iPhone and Android have a dedicated blocking section where you can enter numbers manually. The exact path differs between phones, but the result is the same: calls and texts from that number stop reaching you.

Some calls come from numbers that change each time, or from services that mask their real number. For those, your phone's built-in tools have limits. Your carrier (Verizon, AT&T, T-Mobile, or whoever you pay for service) offers additional filtering, and third-party apps can catch patterns that your phone alone cannot.

Key Takeaways

  • The quickest block is from your recent calls list: find the number, tap and hold, and select "Block this caller."
  • iPhone blocks are found under Settings > Phone > Blocked Contacts; Android blocks are under Settings > Phone > Blocked Numbers (exact path varies by manufacturer).
  • Your phone's built-in blocking stops calls and texts from that specific number, but does not stop spoofed or masked numbers.
  • Your carrier offers free or low-cost call filtering that catches spam patterns your phone cannot, and works even if the number changes.
  • Blocked callers can still leave voicemail, and you can unblock a number at any time from the same settings menu.

Blocking a single number from your call history

This is the method most people use because it takes seconds and requires no navigation through settings. Open your Phone app and go to the "Recents" or "Call History" tab. Scroll to find the number you want to block.

On iPhone, tap the small circle with an "i" next to the number, scroll down, and tap "Block this Caller." On Android, press and hold the number until a menu appears, then tap "Block" or "Block number" (the exact wording depends on your phone's manufacturer — Samsung, Google Pixel, OnePlus, and others phrase it slightly differently, but the option is always there). After you confirm, that number is blocked.

The block takes effect right away. If the same number calls again, it goes to voicemail without your phone ringing or notifying you. You will not see a missed call notification either. Text messages from that number also stop reaching your inbox.

Blocking a number through your phone's settings

Use this method if you want to block a number you have not received a call from yet, or if you prefer to manage all your blocks in one place. On iPhone, open Settings, tap Phone, then tap Blocked Contacts. Tap "Add New" and enter the phone number or select a contact from your list. On Android, open Settings, tap Phone or Call Settings (the name varies), find Blocked Numbers or Do Not Disturb, and tap the plus icon to add a number manually.

Once you enter the number, it is blocked when ready. You can add as many numbers as you need. To unblock someone, go back to the same menu, find their number in the list, and tap "Unblock" or delete it from the list.

One important limit: your phone's built-in blocking only works for numbers you know and enter yourself. If a caller uses a spoofed number (a fake number that changes each time, or one that looks like it is from your bank or a local business), your phone cannot block it because the number is different every time.

Using your carrier's call filtering service

Your carrier — Verizon, AT&T, T-Mobile, or another provider — offers filtering tools that work differently than your phone's block list. Instead of blocking one specific number, carrier filtering learns patterns. It can recognize that a call is spam even if the number is spoofed or changes each time, because it looks at the calling pattern, the type of call, and whether other customers have reported it.

Verizon offers Call Filter (free version available, paid version with more features). AT&T offers Call Protect (free and paid versions). T-Mobile offers Scam Shield (free and paid versions). You can turn these on through your carrier's app or website, or sometimes through your phone's settings if your carrier has integrated it there. Most carriers turn on a basic level of filtering automatically, but you can increase the protection level if you want.

Carrier filtering catches most spam and robocalls before they reach you, and it works even when the caller uses a different number each time. The downside is that occasionally a legitimate call gets caught by mistake, so check your carrier's app periodically to see if any calls were filtered that you actually wanted to receive.

Third-party call blocking apps

If your carrier's filtering is not catching enough spam, or if you want more control over what gets blocked, third-party apps like RoboKiller, Nomorobo, or Truecaller add another layer. These apps use crowdsourced data — information from millions of users reporting spam — to identify and block calls before your phone rings.

Most of these apps are free with optional paid upgrades. They work on both iPhone and Android, though iPhone has some limits because Apple does not let third-party apps block calls the same way Android does. On iPhone, these apps can filter calls into a separate list, but they cannot always prevent your phone from ringing. On Android, they have more control and can block calls completely.

The trade-off with third-party apps is that you are sharing information about your calls with a private company. Read the app's privacy policy before you read it. If you do not want to share that data, your carrier's filtering is usually enough for most people.

What happens to blocked callers and their voicemails

When you block someone, they do not get a message saying they are blocked. Their call goes to your voicemail, and they can leave a message if your voicemail is set up. You will not see that voicemail in your regular inbox — it goes to a separate "Blocked Messages" folder that you can check if you want to.

Blocked callers can also send you text messages, but those go to a separate folder as well. You can read them if you choose to, but you will not be notified that they arrived. This is different from some people's expectations — blocking does not prevent someone from contacting you, it just prevents you from being interrupted by them.

If you change your mind and want to hear from someone again, unblocking takes the same few seconds as blocking did. Go back to your blocked list, find the contact, and tap "Unblock." They will be able to reach you normally again.

Blocking unknown numbers and "No Caller ID" calls

Some calls come in with no number displayed, or with "Unknown Caller" or "No Caller ID" shown. You cannot block these the same way you block a specific number, because there is no number to block. Instead, you can silence them through your phone's settings.

On iPhone, go to Settings > Phone > Silence Unknown Callers. Turn this on, and calls from numbers not in your contacts will go straight to voicemail without ringing. On Android, the option is usually under Settings > Call Settings > Spam Protection or Block Unknown Callers, though the exact name varies by phone. When this is on, your phone still receives the calls, but you are not interrupted.

The downside is that legitimate calls from doctors' offices, delivery services, or businesses you do business with will also go to voicemail. You will need to check your voicemail regularly to make sure you do not miss something important. If you turn this setting on, check your voicemail at least once a day.

Frequently Asked Questions

Can someone tell if I blocked them?

No. When you block someone, their call goes to your voicemail, and they hear a normal voicemail greeting. They do not get a message saying they are blocked. However, if they call repeatedly and always reach voicemail, they may suspect it, but your phone does not tell them directly.

What if I block someone by accident?

Open your blocked list (Settings > Phone > Blocked Contacts on iPhone, or Settings > Phone > Blocked Numbers on Android), find their name, and tap "Unblock." They can call you normally again when ready. You can unblock and reblock numbers as many times as you need.

Do I need to pay to block calls?

No. Your phone's built-in blocking is free. Your carrier's basic filtering is also free. Third-party apps are free to read, though some offer paid upgrades for extra features. You do not need to pay anything to stop calls from reaching you.

Will blocking stop text messages too?

Yes. When you block a number, both calls and text messages from that number are blocked. Text messages go to a separate folder instead of your main inbox, and you are not notified when they arrive. You can read them if you want to by checking your blocked messages folder.

Can I block a number that keeps changing?

Your phone's block list cannot catch a number that changes every time, because you would have to add hundreds of numbers manually. Your carrier's filtering service is designed for this — it recognizes spam patterns even when the number is different. Turn on your carrier's call filtering, or read a third-party app like RoboKiller or Truecaller that uses crowdsourced spam data.