Caller ID on international routes is genuinely hard: every country has its own rules, and the CLI you send is only as durable as every hop it crosses. Here is how to think about it and what we can actually fix.
The three failure modes
- CLI missing: the destination shows "unknown" or nothing. Some destination networks strip international CLI by policy; some transit paths lose it. If CLI-guaranteed delivery matters for your traffic, say so - route selection differs for CLI-sensitive traffic.
- CLI garbled or reformatted: a prefix appears, digits are truncated, or the number shows in a local format. Usually a formatting/translation issue on a hop - fixable once we can see the before and after.
- CLI rejected: increasingly, destination regulators require the calling number to be valid, in-country, or pre-registered; calls with non-conforming CLI are refused or relabelled as spam. This is regulation, not a fault.
What to check first
- You are sending CLI in full international E.164 format.
- The CLI you present is a real, allocated number - invalid or unallocated CLI is the fastest route to blocked calls under modern anti-spoofing rules.
- The issue is consistent (one destination? one CLI range? all traffic?).
What to send us
Called number, presented CLI, what the far end actually displayed, timestamps and 3+ examples. If it is a compliance rejection we will tell you the destination's rule; if it is a transit fault we will chase the hop that mangles it. Be explicit whether your traffic REQUIRES CLI delivery - it changes how we route it.
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