Secret Codes guide
Silence Unknown Callers on iPhone: How It Works
By Muhammad Shahid · · 3 min read
Quick answer
Send calls from numbers you don't know straight to voicemail. iOS compares each incoming number against your contacts, your outgoing call history and numbers found in Mail and Messages. Anything else is silenced, sent to voicemail, and still listed in Recents. It is a blunt instrument but very effective against spam, and it works without any carrier involvement.
Secret CodesDial codes, SIM & network test · Free on the App StoreDownload free →| What it does | Send calls from numbers you don't know straight to voicemail. |
|---|---|
| Published for | any iPhone |
| Type | iOS setting |
Send calls from numbers you don't know straight to voicemail. This page explains what it does, how to use it on an iPhone and which carriers it applies to.
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What is Silence Unknown Callers?
iOS compares each incoming number against your contacts, your outgoing call history and numbers found in Mail and Messages. Anything else is silenced, sent to voicemail, and still listed in Recents.
It is a blunt instrument but very effective against spam, and it works without any carrier involvement.
Important: Calls from delivery drivers, doctors' offices and schools are commonly silenced too. Check your voicemail and Recents if you are expecting something important.
How do I do it?
- Open the Settings app.
- Tap Apps, then Phone (on earlier versions of iOS, tap Phone directly).
- Tap Silence Unknown Callers.
- Turn the switch on.
Which carriers does this apply to?
| Published for | any iPhone |
|---|---|
| Type | iOS setting |
| Good to know | Built into iOS 13 and later. Works on every carrier. |
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- Show My Caller ID Switch
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- #787#: Check Scam Block Status (T-Mobile)
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- #632#: Turn Off Scam Block (T-Mobile)
- #662#: Turn On Scam Block (T-Mobile)
See all caller id codes or every category of iPhone codes.
How Secret Codes helps
Secret Codes keeps this and every other entry a search away. Pick your carrier once and each entry says whether it is published for your line. You can save favourites, add a private note, and record whether a code worked on your line.
Frequently asked questions
What is Silence Unknown Callers on iPhone?
Send calls from numbers you don't know straight to voicemail. iOS compares each incoming number against your contacts, your outgoing call history and numbers found in Mail and Messages. Anything else is silenced, sent to voicemail, and still listed in Recents.
What else should I know about Silence Unknown Callers?
It is a blunt instrument but very effective against spam, and it works without any carrier involvement.
What are the steps for Silence Unknown Callers?
1. Open the Settings app. 2. Tap Apps, then Phone (on earlier versions of iOS, tap Phone directly). 3. Tap Silence Unknown Callers. 4. Turn the switch on.
Where do I find Silence Unknown Callers?
In the Settings app on your iPhone.
Is there a dial code for Silence Unknown Callers?
No. On iPhone this is not a dial code, so you use the steps on this page instead.
Which carriers does Silence Unknown Callers work on?
It is published for any iPhone. Built into iOS 13 and later. Works on every carrier.
Is there anything to watch out for with Silence Unknown Callers?
Calls from delivery drivers, doctors' offices and schools are commonly silenced too. Check your voicemail and Recents if you are expecting something important.
Does Silence Unknown Callers work on Android phones too?
These steps are for iPhone. Android phones have their own menus.
Will Silence Unknown Callers work outside the US?
The iPhone steps stay the same, although some features depend on your carrier and region.
What if Silence Unknown Callers does not work on my iPhone?
Check that it applies to your carrier first, because carriers decide which services they offer and can change them. If it should apply to your line, contact your carrier.
What is related to Silence Unknown Callers?
Show My Caller ID Switch. The permanent caller ID toggle built into iOS.
What else is in this category?
Manage Blocked Numbers. Review and edit everyone you have blocked.
Sources
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