To silence unknown callers on an iPhone 15 with iOS 26, open Settings > Apps > Phone > Screen Unknown Callers and choose Silence. On iOS 18 or earlier, turn on Silence Unknown Callers in the Phone settings instead. Calls from numbers that aren’t in your contacts, and that you haven’t called recently, then go straight to voicemail without ringing, and they still appear in your Recents list.
Applies to: iPhone 15 and other iPhones with iOS 26, iOS 18 or iOS 17. Last reviewed October 7, 2026.
On iOS 26
- Open Settings > Apps > Phone.
- Tap Screen Unknown Callers.
- Choose one option:
- Silence: unknown callers go straight to voicemail without ringing.
- Ask Reason for Calling: your iPhone answers, asks for the caller’s name and reason, and then shows you their answer so you can decide whether to pick up. See how to use call screening on iPhone.
- Never: all calls ring as usual.
On iOS 18 and iOS 17
- Open Settings > Apps > Phone on iOS 18, or Settings > Phone on iOS 17.
- Tap Silence Unknown Callers and turn it on.
Which calls still ring
- Numbers saved in your Contacts.
- Numbers you’ve called recently.
- Numbers Siri has found in your emails and messages (Siri Suggestions).
Add anyone you’re expecting to hear from, such as a doctor’s office or delivery driver, to your contacts so their calls get through. If you call emergency services, your iPhone temporarily turns silencing off so emergency services can call you back.
Find silenced calls
- Silenced calls appear in the Phone app’s Recents list. On iOS 26, use the filter to show Unknown Callers.
- Callers who leave a message appear in Voicemail, so you won’t miss anything important.
- You don’t get a ringtone or vibration, but you may see a missed call notification.
Filter spam calls too
Your carrier and iOS can mark suspected spam calls. On iOS 26, turn on Call Filtering > Spam in Settings > Apps > Phone to send them to voicemail and a separate Spam list. Many carriers also offer free spam-blocking apps or settings; see how to block spam calls on iPhone 15.
Silence unknown text messages
For texts, open Settings > Apps > Messages and turn on Screen Unknown Senders (iOS 26) or Filter Unknown Senders (earlier versions). Messages from unknown numbers move to a separate list without notifications.
Silence everything for a while
To silence all calls, not just unknown ones, use a Focus such as Do Not Disturb or Sleep. Swipe down from the top-right corner, tap Focus and choose one. To set up a bedtime schedule, see how to change your iPhone’s sleep settings.
Turn it off again
Go back to Settings > Apps > Phone. On iOS 26, set Screen Unknown Callers to Never; on earlier versions, turn off Silence Unknown Callers. It’s worth doing when you’re waiting for a call from a new number, such as a job interview, a hospital or a courier, and turning it back on afterward.
Which option should you use?
- Silence: best if you get lots of spam and rarely hear from new numbers. Nothing rings, and genuine callers can leave a voicemail.
- Ask Reason for Calling: best if you often get legitimate calls from unknown numbers, such as tradespeople or appointment reminders. Robocalls usually hang up rather than answer the question.
- Blocking a number: best for one persistent caller. It stops calls and messages from that number only.
- Focus: best for quiet time, such as meetings or sleep. It silences everyone except the people you allow.
Troubleshooting
A known caller went to voicemail
Their number isn’t saved in Contacts, or it’s saved in a different format. Add the number to the contact card, including the country code if needed.
Unknown calls still ring
Check that the setting is on, and that the caller isn’t someone you’ve phoned recently. Calls through apps like WhatsApp follow that app’s settings, not the iPhone’s.
I need to stop one specific number
Block it instead. See what happens when you block someone on iPhone.
Frequently asked questions
Will the caller know I silenced them?
No. The call rings on their end until it goes to voicemail, the same as when you don’t answer.
Does it work on iPhone 14, 16 and 17 too?
Yes. The setting depends on the iOS version, not the iPhone model. Any iPhone that can run iOS 26 has Screen Unknown Callers.
Related: how to show missed calls on the iPhone Lock Screen.
Related: turn off text message sounds on iPhone.
Related: change the ringtone on an iPhone 13.
Related: how to set up voicemail on iPhone 15.
Related: how to turn off Do Not Disturb on iPhone.
Matt Jacobs has been working as an IT consultant for small businesses since receiving his Master’s degree in 2003. While he still does some consulting work, his primary focus now is on creating technology support content for SupportYourTech.com.
His work can be found on many websites and focuses on topics such as Microsoft Office, Apple devices, Android devices, Photoshop, and more.