Getting Started with CNAM Caller ID

Twilio supports Caller ID name (CNAM) lookups in a number of ways. Continue reading for an overview of how CNAM works with Twilio, and common questions.

This guide covers the following information:

What is CNAM?

Caller ID Name (CNAM) is a service used in telephone networks to provide the name of the calling party. The name can be a business or person, represented as a string of text no longer than 15 characters.

Telephone carriers are responsible for populating one of several authoritative databases with subscriber data, known as CNAM repositories and collectively referred to as the Line Information Database (LIDB).

Where does CNAM lookup work?

Caller name Lookup is sourced by authoritative CNAM data, which is only supported by carriers in the U.S, and a portion of carriers in Canada. CNAM lookups for phone numbers from other countries are not supported.

How can I lookup CNAM with Twilio?

Twilio offers customers a number of ways to lookup CNAM entries:

  • Manual phone number query: Twilio's Lookup API allows users to search for CNAM entries for phone numbers in the US and Canada. For full details, see Getting Started with the Twilio Lookup API.
  • Elastic SIP Trunking: Twilio Elastic SIP Trunking allows users to enable automatic CNAM lookups for incoming (SIP Origination) calls on each trunk independently. This feature can be set on the Trunk origination settings page in Console, or via the REST API.
  • Programmable Voice: Twilio Programmable Voice allows users to enable automatic CNAM lookups for incoming calls on each phone number independently. This feature can be set on the Phone number configuration page in Console, or via the REST API.

Each CNAM lookup, regardless of the method, costs $0.01.

How do I edit or remove a CNAM entry?

If you have concerns about privacy and do not want your name to appear in Caller Name Lookup queries, or you would like to update the value returned by CNAM, please contact your carrier. Your carrier is the only authority for the CNAM value associated with your phone number. They can change the name or remove the name entirely. Each carrier has a different policy on whether or not they automatically opt their subscribers into CNAM.

For questions about CNAM changes to Twilio phone numbers, please collect the following information:

  • Twilio phone number(s)
  • Requested CNAM change(s)

Once you have gathered these details, please contact our Support team, and submit a request with this information. Our specialists will investigate your request, and respond with the options available to us.

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