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

On most phones, blocking happens in the Phone or Messages app — the same place you make calls or read texts. When you block a number, calls and texts from that number stop reaching you; they either go to voicemail (on your phone) or disappear entirely (depending on your carrier and device). The blocked caller does not get a notification that they were blocked, but they may notice their calls go straight to voicemail.

The exact steps differ between iPhone and Android, and some carriers offer additional blocking through their own apps or online accounts. This guide covers the built-in methods that work without paying extra or downloading third-party software.

Key Takeaways

  • On iPhone, open the Phone app, find the number in your recent calls or contacts, swipe left (or tap the info icon), and select Block This Caller.
  • On Android, open the Phone app, press and hold the number in your call history, and tap Block Number.
  • You can also block a number directly from a text message by opening the conversation and selecting Block Contact or Block Sender.
  • Blocked numbers can still leave voicemail on some carriers, so check your carrier's settings if you want to block voicemail too.
  • You can unblock a number at any time by finding it in your blocked list and selecting Unblock.

Blocking a number on iPhone

Open the Phone app and go to the Recents tab at the bottom. Find the number you want to block — it will show as a phone number or a contact name. Tap the small circle with an "i" on the right side of that entry. Scroll down and tap Block This Caller, then confirm by tapping Block Contact.

If the number is saved in your contacts, you can also open the Contacts app, find the person, tap Edit in the top right, scroll to the bottom, and tap Block This Caller. If you want to block a number that texted you, open the Messages app, find the conversation, swipe left on it, tap the trash icon, and a menu will appear — tap Block, then confirm.

Once blocked, calls from that number will go straight to voicemail and you will not see a notification. Text messages will not appear in your message threads. The blocked number stays blocked until you manually unblock it.

Blocking a number on Android

Open the Phone app (sometimes called Dialer) and go to the Recents or Call History tab. Press and hold the number you want to block until a menu appears. Tap Block Number or Block Contact, then confirm. The exact wording depends on your phone manufacturer — Samsung phones may say Block, while Google Pixel phones say Block Number.

You can also block from your Contacts app: open it, find the person, tap the three dots in the top right, and select Block Number. If you want to block a number from a text, open the Messages app, find the conversation, press and hold it, and look for a Block option in the menu that appears.

On Android, blocked numbers typically cannot call you or send you texts, though some carriers allow blocked callers to leave voicemail. Check your carrier's website or call their customer service if you want to block voicemail from specific numbers.

Blocking numbers from text messages

You do not have to find a number in your call history to block it — you can block directly from a text conversation. Open your Messages app, find the conversation with the number you want to block, and look for a menu option. On iPhone, swipe left on the conversation and tap Block. On Android, press and hold the conversation and tap Block Number.

This method is useful when you receive texts from a number you have never called, or when you want to block someone without opening the Phone app. The blocking works the same way: future texts from that number will not reach you.

Finding and managing your blocked list

On iPhone, open Settings, scroll down to Phone, tap Blocked Contacts, and you will see every number you have blocked. To unblock someone, swipe left on their name and tap Unblock. You can also go to Messages in Settings and check Blocked Contacts there separately — blocking in one app does not always block in the other, depending on your iOS version.

On Android, open the Phone app, tap the three dots in the top right, go to Settings, and look for Blocked Numbers or Blocked Contacts. The exact path varies by manufacturer. Tap any number in the list and select Unblock to remove them from your blocked list.

Keep in mind that your blocked list is stored on your phone, not in the cloud. If you get a new phone, your blocked numbers will not transfer automatically unless you back up and restore your phone data.

What happens when you block a number

When you block a number, that caller cannot reach you through calls or text messages. On most carriers, their call goes to your voicemail, but they do not hear a message saying they are blocked — it sounds like a normal voicemail. Some carriers send a text to the blocked caller saying the message could not be delivered, which may tip them off that they are blocked.

The blocked caller cannot see that they are blocked just by calling you. They will only know if they try multiple times and always reach voicemail, or if they send a text and never get a response. Blocking is not a public announcement — it is a private filter on your phone.

If a blocked number calls from a different phone number, that new number will reach you normally. Blocking works on the specific number, not the person, so someone determined to contact you can use a different phone.

When blocking is not enough

If you are receiving calls from many different numbers, or if a blocked number keeps calling from new numbers, blocking individual numbers becomes tedious. Your carrier may offer a spam-blocking service through their website or a separate app — check your carrier's customer service page to see what they offer. Some carriers charge a small monthly fee for advanced blocking, while others include it free with certain plans.

You can also report spam or harassment to your carrier and to the Federal Trade Commission at reportfraud.ftc.gov. If the calls are threatening or harassing, contact local police. Blocking handles the when ready problem of stopping calls from reaching you, but reporting helps authorities track patterns of abuse.

Frequently Asked Questions

Can a blocked number tell they are blocked?

Not directly. Their call goes to voicemail like a normal unanswered call. They might suspect they are blocked if they call multiple times and always reach voicemail, or if texts never get a delivery confirmation, but your phone does not send them a message saying they are blocked.

What if I block someone by accident?

You can unblock them when ready. On iPhone, go to Settings > Phone > Blocked Contacts, swipe left on the name, and tap Unblock. On Android, open the Phone app, go to Settings > Blocked Numbers, and tap Unblock next to the number. Once unblocked, they can call and text you normally again.

Do blocked numbers still leave voicemail?

Usually yes. Most carriers send blocked calls to voicemail, so the caller can still leave a message. If you want to prevent voicemail from blocked numbers, check your carrier's website or call their customer service — some offer a setting to block voicemail separately, though not all do.

Will my blocked list transfer to a new phone?

Only if you back up and restore your phone data. When you set up a new iPhone or Android phone and restore from a backup, your blocked numbers come with it. If you set up a new phone without restoring a backup, you will need to block those numbers again.

Can I block a number I do not have saved as a contact?

Yes. You can block any phone number that appears in your call history or message threads, whether or not it is saved in your contacts. Find the number in your recent calls or messages and follow the blocking steps for your phone type.