Sometimes inbound calls in Aircall may display as “Anonymous”, “Unknown”, or with no caller ID. This article explains why this happens and how to diagnose the root cause.

 

🔹 1. How Caller ID Works in Aircall:

Caller ID (CLI) is carried in the SIP signalling or PSTN metadata from the upstream telecom carrier. Aircall does not generate or modify Caller ID — we display exactly what the carrier provides. If the upstream provider does not send CLI, Aircall will show Anonymous.

 

 

🔹 2. Common Reasons for Anonymous Caller ID:

1-Caller intentionally hides CLI Caller has enabled “Hide Number” or “Private Number.” Aircall will show Anonymous because no CLI is present in signaling. 

2-Forwarded calls without CLI pass-through If your Aircall number receives calls via call forwarding from another provider, the forwarding carrier may strip or replace CLI. Example: PBX → Carrier → Aircall. 

3-Carrier-level restrictions Some countries or carriers block third-party CLI for regulatory reasons.

 

 

🔹 3. Steps to Diagnose:

1-Test a direct call to your Aircall number If caller ID displays correctly, but forwarded calls show Anonymous → the issue is with the forwarding provider. 

2-Check multiple calls from different sources If all calls show Anonymous, it could be a carrier restriction. If only some calls show Anonymous, the caller likely hide their ID. 

. 

 

🔹 4. What You Can Do:

If the issue is forwarding-related: Contact the forwarding provider and ask if they support CLI pass-through.

If the issue is regulatory: Be aware that some countries mandate anonymous delivery for forwarded or international CLI.

If it’s caller-driven: Nothing can be done — if the caller hides their ID, Aircall cannot override this. 

 

 

✅ Key Takeaway

Aircall always displays the caller ID as delivered by the carrier.

If numbers appear as Anonymous, the cause is usually:

Caller intentionally withheld their ID, Forwarding provider removed CLI, or Carrier/regulatory restrictions.