The fastest way to block unknown callers

iPhone has a built-in setting that sends calls from numbers not in your contacts straight to voicemail. Open Settings, tap Phone, then turn on Silence Unknown Callers. This stops the ringing and notification entirely — the call goes to voicemail without interrupting you.

This setting works for any number you have not saved. If someone calls from a number you have contacted before, or from a business you have called, the call will still ring through. The trade-off is simplicity: you do not have to manage a block list, but you also will not see a missed call notification unless the caller leaves a voicemail.

If you want to see that an unknown number called but still silence it, use Do Not Disturb instead. Go to Settings > Focus > Do Not Disturb, turn it on, and set it to allow calls only from your contacts. Unknown numbers will still ring once, then go silent.

Key Takeaways

  • Silence Unknown Callers in Settings > Phone sends all calls from unknown numbers to voicemail without ringing or notifying you.
  • You can block specific numbers manually by opening the call, tapping the info icon, and selecting Block This Caller.
  • Do Not Disturb with contacts-only mode lets unknown calls ring once before silencing, so you see them in your call log.
  • Blocked callers can still leave voicemails, but their messages will not show notifications and appear in a separate section.
  • Third-party apps like Nomorobo and RoboKiller can filter spam calls before they reach your phone, but require a subscription.

Blocking individual numbers you have already received

If a specific number has called you and you want to block it, open the Phone app and find the call in your recent list. Tap the circled i icon next to the number, scroll down, and tap Block This Caller. That number will never ring through again.

You can also block a contact directly. Open Contacts, find the person or business, tap Edit, scroll to the bottom, and tap Block This Caller. This prevents calls, texts, and FaceTime requests from that contact.

To see your full block list or unblock someone, go to Settings > Phone > Blocked Contacts. Swipe left on any name to unblock them. Blocked callers can still leave voicemails, but you will not receive a notification — their messages appear in a separate section at the bottom of your voicemail list.

Using Do Not Disturb to filter calls by contact status

Do Not Disturb is more flexible than Silence Unknown Callers because it lets you see that a call came in, even though it does not ring. Go to Settings > Focus > Do Not Disturb and turn it on. Tap Calls and select Contacts Only.

With this setting active, calls from people in your contacts will ring normally. Calls from unknown numbers will ring once, then silence. You will see the missed call in your call log and can call back if you recognize the number. This is useful if you want to catch legitimate calls from businesses or services you use, but do not want constant interruptions from spam.

You can schedule Do Not Disturb to turn on automatically at certain times — for example, every evening after 9 p.m. or during work hours. Tap Schedule and set your preferred times. This way you do not have to remember to turn it on and off manually.

Filtering spam calls with third-party apps

Apps like Nomorobo, RoboKiller, and Truecaller use databases of known spam and scam numbers to block calls before they reach your phone. These apps require a subscription — typically five to ten dollars per month — but they catch more spam than iPhone's built-in tools because they update their block lists constantly.

To use a third-party app, read it from the App Store, open Settings > Phone > Call Blocking & Identification, and enable the app. The app will then filter incoming calls in the background. Some apps also show you the reason a call was blocked — for example, "Likely spam" or "Known scammer" — so you can decide whether to unblock it.

The downside is that these apps cost money and require you to trust a private company with your call data. iPhone's built-in settings are free and do not share your information with third parties. Use a paid app only if Silence Unknown Callers or Do Not Disturb is not blocking enough spam for you.

What happens when you block a number

When you block someone, they cannot call you, text you, or reach you on FaceTime. Their calls go straight to voicemail, but they will not hear a busy signal or a message saying they are blocked — it will sound like a normal voicemail greeting. They can still leave a message, but you will not be notified.

Blocked callers can still see that their calls went through from their end, so they may not realize they are blocked. If you want to unblock someone later, go to Settings > Phone > Blocked Contacts, swipe left on their name, and tap Unblock.

Blocking is not the same as reporting spam. If you want to report a number as spam or scam, open the call in your recent list, tap the i icon, and select Report as Spam or Junk. This sends information to Apple and your carrier to help them identify patterns in spam calls.

Preventing spam calls before they reach you

Your carrier — Verizon, AT&T, T-Mobile, or another provider — may offer spam filtering as part of your plan or as a paid add-on. Call your carrier's customer service to ask whether they have a spam-blocking service and how to turn it on. Some carriers include it automatically; others charge a few dollars per month.

You can also reduce spam by not sharing your number publicly. Avoid posting your phone number on social media, websites, or online forms unless necessary. If you have already shared it widely, consider getting a new number — carriers can usually do this for free if you ask.

Never answer calls from numbers you do not recognize, and do not press buttons or say anything when an automated voice asks you to confirm your number. Responding confirms that your number is active and monitored, which makes you a target for more spam. If you are unsure whether a call is real, hang up and call the organization back using a number from their official website.

Frequently Asked Questions

Will someone know if I block them?

No. Blocked callers will not receive a message saying they are blocked. Their calls go to voicemail like normal, so they may not realize you blocked them unless they try other ways to contact you and notice a pattern.

Can I block calls from a specific area code?

iPhone does not have a built-in feature to block entire area codes. Your best option is to use a third-party app like Nomorobo or RoboKiller, which can filter calls by area code or number pattern. Alternatively, block numbers individually as they call you.

What if a blocked caller leaves a voicemail?

Blocked voicemails appear in a separate section at the bottom of your voicemail list, and you will not receive a notification. You can listen to them anytime by opening the Phone app and tapping Voicemail, then scrolling down to see blocked messages.

Can I block calls from my carrier instead of using iPhone settings?

Yes. Contact your carrier directly to ask about their spam-blocking service. Many carriers offer free or paid options that filter calls at the network level before they reach your phone, which can catch more spam than iPhone's built-in tools.

Does Silence Unknown Callers block calls from businesses I have called before?

No. Silence Unknown Callers only blocks numbers you have never contacted. If you have called a business before, their calls will still ring through even if the number is not saved in your contacts.