How to block an unknown caller on your iPhone
You can block an unknown caller in two ways on iPhone: by blocking the number directly from a recent call, or by using the built-in filtering tools to silence calls from numbers not in your contacts. If you answered the call and want to block that number, go to your Phone app, find the number in your recent calls list, tap the information icon next to it, scroll down, and tap "Block this Caller." If you don't know the exact number or want to prevent calls from unknown numbers altogether, turn on "Silence Unknown Callers" in your Settings instead.
The method you choose depends on whether you have the specific number to block or whether you want a blanket filter. Blocking a single number takes about 30 seconds. Turning on the silence feature takes about 15 seconds but affects all calls from numbers not saved in your phone.
Key Takeaways
- You can block a specific unknown number through the Phone app by tapping the information icon next to a recent call and selecting "Block this Caller."
- The "Silence Unknown Callers" feature in Settings automatically sends calls from unknown numbers to voicemail without ringing your phone.
- Blocked callers can still leave voicemails, which go to a separate folder you can check or delete without listening.
- You can unblock a number at any time by going to Settings > Phone > Blocked Contacts and swiping left on the number.
- Unknown callers include anyone not saved in your contacts, so "Silence Unknown Callers" will affect legitimate calls from businesses, doctors' offices, and other services you don't have saved.
Block a specific number from your recent calls
If you have a recent call from the unknown number you want to block, this is the fastest method. Open the Phone app on your home screen and tap the "Recents" tab at the bottom. Look through your call history for the number you want to block.
Tap the small information icon (a circle with an "i" inside) next to the number. On the next screen, scroll down until you see the "Block this Caller" button in red text. Tap it, then confirm by tapping "Block Contact" in the popup that appears. The number is now blocked — calls from it will go straight to voicemail without ringing your phone.
Use "Silence Unknown Callers" to filter all unknown numbers
If you don't have the specific number or want to stop all calls from unknown contacts at once, use the "Silence Unknown Callers" feature. This setting sends any call from a number not saved in your contacts directly to voicemail. Open Settings on your home screen, tap "Phone," then scroll down and toggle "Silence Unknown Callers" to the on position (it will turn green).
This feature is useful if you receive many spam or scam calls, but be aware that it will also silence calls from legitimate businesses, medical offices, schools, and other services you haven't saved as contacts. If you turn this on, check your voicemail regularly so you don't miss important calls.
Check your blocked contacts list
To see all the numbers you have blocked, go to Settings > Phone > Blocked Contacts. This list shows every number you have manually blocked through the "Block this Caller" option. You cannot block numbers from this screen directly — you can only unblock them.
If you want to unblock a number, find it in the list, swipe left on it, and tap the trash icon that appears. The number will be unblocked immediately, and calls from it will ring your phone again.
What happens when you block a caller
When you block a number on iPhone, the caller cannot reach you by phone call. Their call goes directly to your voicemail without your phone ringing or showing a notification. They will hear either a message saying the call cannot be completed or your voicemail greeting, depending on your carrier.
Blocked callers can still leave voicemails, but those messages go to a separate "Blocked Messages" folder in your voicemail. You can listen to, delete, or save these messages without them appearing in your main voicemail inbox. Text messages from blocked numbers are also silenced — they arrive but do not trigger notifications.
Unblock a number if you blocked it by mistake
If you blocked a number and later realize it was someone you wanted to hear from, you can unblock it quickly. Go to Settings > Phone > Blocked Contacts, find the number in the list, and swipe left on it. A red trash icon will appear on the right side. Tap the trash icon to unblock the number.
Once unblocked, calls from that number will ring your phone normally again. There is no confirmation step, so the number is unblocked as soon as you tap the trash icon. If you change your mind immediately, you can block it again using the same process.
When to use each blocking method
Use the "Block this Caller" method when you have received a call from a specific number you want to stop. This is best for numbers that have already contacted you and you have decided you do not want to hear from them again. It takes slightly longer but gives you precise control over which numbers are blocked.
Use "Silence Unknown Callers" when you receive frequent calls from many different unknown numbers and want a blanket filter. This is common if you are dealing with spam or scam calls. Keep in mind that this will also block calls from services you may need to hear from, so check your voicemail regularly. You can turn this feature on and off at any time depending on your needs.
Frequently Asked Questions
Will the person I blocked know that I blocked them?
No. When you block someone on iPhone, they will not receive a notification that you blocked them. Their call will go to voicemail, and they may assume you did not answer. There is no way for them to know for certain that they are blocked.
Can I block a number if I did not answer the call?
Yes. Even if you did not answer, the number will appear in your recent calls list. Tap the information icon next to it and select "Block this Caller." You can also turn on "Silence Unknown Callers" to block all future calls from unknown numbers without needing the specific number.
What if I block a number but still want to see their voicemails?
Blocked voicemails go to a separate folder. Open the Phone app, tap "Voicemail," then look for a "Blocked Messages" or similar section at the bottom of your voicemail list. You can listen to, delete, or save these messages from there.
Does "Silence Unknown Callers" block text messages too?
No. "Silence Unknown Callers" only affects phone calls. Text messages from unknown numbers will still arrive normally. If you want to block text messages from a specific number, you need to block that number individually using the "Block this Caller" method.
Can I block a number without going through the Phone app?
Yes. If someone texts you from a number you want to block, open the Messages app, find the conversation, swipe left on it, tap "More," then tap "Block." You can also block a contact directly from your Contacts app by opening their card and tapping "Block this Caller" at the bottom.