The fastest way depends on your phone type
On most phones, blocking a caller takes one step: find the number in your call history or contacts, tap or press a menu option, and select "block" or "block this caller." The blocked person can still leave voicemail, but their calls won't ring through and won't appear in your call log. Text messages from blocked numbers usually don't arrive either, though this varies by phone and carrier.
iPhones and Android phones handle blocking slightly differently, but both let you block from the Phone app, Messages app, or Contacts app. The end result is the same — the caller reaches your voicemail instead of your phone ringing.
If you don't know the number or it's not in your contacts yet, you can still block it. Most phones let you block a number directly from an incoming call screen or from your recent calls list, even if you've never saved that contact before.
Key Takeaways
- On iPhone, open the Phone app, find the number in Recents, swipe left, and tap Block This Caller; on Android, long-press the number and select Block.
- Blocked callers reach your voicemail instead of ringing your phone, and their calls don't show in your call history.
- You can block a number from an incoming call screen without saving it to your contacts first.
- Carriers like Verizon, AT&T, and T-Mobile offer additional blocking tools through their own apps, which can catch spam calls before they reach your phone.
Blocking on iPhone
Open the Phone app and go to the Recents tab at the bottom. Find the number you want to block, swipe left on it, and tap the red circle with a line through it. A menu appears — tap "Block This Caller." The number is now blocked.
You can also block from the Contacts app: find the person, tap the info button (a circle with an "i"), scroll down, and tap "Block This Caller." Or block during an incoming call by tapping the red phone icon to decline, then tapping "Block This Caller" from the options that appear.
To see your blocked list or unblock someone, open Settings, go to Phone, and tap Blocked Contacts. You'll see everyone you've blocked and can tap "Edit" to remove anyone from the list.
Blocking on Android
Open the Phone app and go to the Recents or Call History tab. Long-press the number you want to block until a menu appears, then tap "Block number" or "Block." The exact wording depends on your phone manufacturer and Android version.
You can also block from Contacts: find the person, tap the three dots or menu icon, and select "Block number." During an incoming call, tap the red phone icon to decline, and some Android phones will show a "Block" option immediately after.
To manage your blocked list, open the Phone app, tap the three dots or menu icon at the top, and look for "Blocked numbers" or "Settings." You can see everyone you've blocked and unblock them from this menu.
Carrier-level blocking tools
Your phone company offers its own blocking service, separate from your phone's built-in feature. Verizon Call Filter, AT&T Call Protect, and T-Mobile Scam Shield can block calls before they reach your phone at all — they catch spam and robocalls at the network level, not just on your device.
These tools are often free with a basic tier that blocks known spam numbers. Paid versions add features like blocking by category (robocalls, telemarketers, suspected fraud) and letting you see blocked calls in a separate log. You download the carrier's app or enable the service through your account online.
Carrier blocking is useful if you get many spam calls, because it stops them before they ring your phone. Phone-level blocking is better for blocking specific people you know — like an ex or a persistent caller — because you control exactly who's on the list.
What happens when you block someone
When you block a caller, their calls go straight to your voicemail. They won't hear a busy signal or a message saying they're blocked — they'll just reach your voicemail greeting as if your phone was off or you didn't answer. They may not realize they're blocked.
Text messages from blocked numbers usually don't deliver to your phone, though some Android phones let you choose whether to block texts separately from calls. The sender won't get a delivery confirmation, so they may think the message went through.
Blocked calls and texts don't appear in your call history or message threads. If you unblock someone later, you won't see the calls or texts they sent while blocked — those are gone from your phone's record.
Unblocking a caller
To unblock someone on iPhone, open Settings, go to Phone, tap Blocked Contacts, and swipe left on the name you want to unblock. Tap "Unblock."
On Android, open the Phone app, tap the menu icon, go to Blocked numbers, and tap the X or minus sign next to the number you want to unblock. The exact steps vary by manufacturer, but the blocked list is always in the Phone app settings.
Once you unblock someone, they can call and text you normally again. Their calls will ring your phone and appear in your call history.
When blocking doesn't work
If someone keeps calling from different numbers, blocking each one individually becomes tedious. This is common with robocalls and spam — they cycle through numbers to get around blocks. In this case, carrier-level blocking or a third-party app like RoboKiller or Nomorobo may work better, because they identify spam patterns rather than just blocking specific numbers.
If someone is harassing you repeatedly, even from new numbers, document the calls and consider reporting them to your carrier or local police. Blocking is a tool for managing unwanted calls, but it's not a solution for harassment or threats.
Frequently Asked Questions
Can someone tell if I blocked them?
Not directly from your phone. They'll reach your voicemail instead of getting a busy signal, so they might suspect they're blocked, but they won't get a notification saying so. Some people test by calling from a different number to see if that one goes through.
Do blocked callers still reach my voicemail?
Yes. Blocked callers hear your voicemail greeting and can leave a message, but you won't be notified that they called. The voicemail sits in your voicemail box, and you can listen to it if you check, but it won't alert you the way a normal call would.
What's the difference between blocking and Do Not Disturb?
Do Not Disturb silences all calls and notifications on your phone, but the caller still reaches your voicemail and the call appears in your history. Blocking prevents a specific person from reaching you at all — their call goes to voicemail, but you won't see it in your call log. Do Not Disturb is for temporary silence; blocking is permanent until you unblock.
Can I block a number I don't recognize?
Yes. You don't need to save someone to your contacts to block them. Just find the number in your recent calls, long-press it, and select block. This is useful for spam calls or numbers you don't want to hear from again.
If I block someone on my phone, are they blocked on iMessage or WhatsApp too?
No. Phone-level blocking only affects calls and text messages through your carrier. If you want to block someone on iMessage, WhatsApp, Facebook Messenger, or another app, you have to block them separately in that app's settings.