When you enable Truecaller’s identification features, iOS sees the incoming number as "identified" rather than "unknown." Because Apple’s Silence Unknown Callers setting only triggers for numbers it doesn't recognize at all, it allows identified calls to ring through—even if they aren't in your contacts.
This is an iOS system limitation
This is a core behavior of the iOS operating system. Once a third-party app like Truecaller provides a name for a number, Apple’s system logic considers that caller "known" and bypasses the silence filter. Currently, third-party apps do not have the permission to override this system logic.
How to Help Fix This
We want to give you the choice to silence calls even if they are identified. To make this happen, we need Apple to update their feature. Please report this directly to Apple via Feedback Assistant.
How to report to Apple:
Open Feedback Assistant: Type
applefeedback://into Safari on your iPhone or find the app (available on beta versions). If on a public version, use feedback.apple.com.Start a New Report: Select iOS & iPadOS
Please provide a descriptive title: Write Silence Unknown Callers not working with Caller ID apps
Which area are you seeing an issue with: Select Phone app
What type of feedback are you reporting: Select Incorrect/Expected Behavior
What does the Phone app issue you are seeing involve: Select Something else on this list
Are you using an eSIM: Select No
Use this Description: > "When 'Silence Unknown Callers' is enabled, calls identified by a Call Directory extension (like Truecaller) still ring. iOS should treat 'Identified' callers as 'Unknown' if they are not in my personal Contacts list. The purpose of my Caller ID app is to identify a caller but that doesn't make them a known caller and should be silenced if I have the feature turned on. Moreover, for silenced calls, I would like to see the Caller ID name in Recents so as to decide whether or not to call back."
Submit & Share: Once submitted, you will receive a Feedback ID (e.g., FB1234567).
Note: If you’re comfortable, please share your Feedback ID with us via our support channel so we can track the volume of reports and escalate this with Apple's engineering team.