Retrieving CNAM Owner Details

Effective February 4, 2027, Vonage will sunset Vonage Number Insights. To ensure uninterrupted support and to provide a more scalable and future-proof solution, we encourage you to migrate to our enhanced offering: Vonage Identity Insights API. The Vonage Identity Insights API consolidates multiple phone number-related datasets into a single, flexible API, allowing you to request real-time information about a phone number and retrieve any combination of insights - such as number formatting, carrier details, SIM Swap and Subscriber Match - in one call.

Please review the Number Insights Transition Guide, which provides detailed guidance on API differences, required changes, and best practices for a smooth transition.

Overview

Vonage's Number Insight Advanced API enables you to retrieve CNAM owner details for many United States phone numbers. This includes landline and cellular numbers for both consumers and businesses.

CNAM is an acronym which stands for Caller ID Name. US networks use it to display the calling party’s name alongside the phone number, to help users identify a caller.

The Number Insight Advanced API only provides CNAM details for US numbers: it cannot return this information for numbers in other countries.

Making the request

Passing cnam=true as an extra parameter in a call to the Advanced API looks up that number's CNAM.

The following example shows how you would request CNAM data using curl:

curl "https://api.nexmo.com/ni/advanced/json?api_key=VONAGE_API_KEY&api_secret=VONAGE_API_SECRET&number=14155550100&cnam=true"

Understanding the response

In the response returned by the Number Insight Advanced API, the following fields relate to CNAM:

  • caller_name: the owner name
  • caller_type: either business or consumer depending on the type of number
  • first_name and last_name: for consumer numbers only

Consumer example

{
    "status": 0,
    "status_message": "Success",
    "lookup_outcome": 1,
    "lookup_outcome_message": "Partial success - some fields populated",
    "request_id": "50793c0c-8025-408f-ab9a-71cbbaf033bf",
    "international_format_number": "14155550100",
    "national_format_number": "(415) 55500100",
    "country_code": "US",
    "country_code_iso3": "USA",
    "country_name": "United States of America",
    "country_prefix": "1",
    "request_price": "0.04000000",
    "remaining_balance": "10.000000",
    "current_carrier": {
        "network_code": "310004",
        "name": "Verizon Wireless",
        "country": "US",
        "network_type": "mobile"
    },
    "original_carrier": {
        "network_code": "310004",
        "name": "Verizon Wireless",
        "country": "US",
        "network_type": "mobile"
    },
    "valid_number": "valid",
    "reachable": "unknown",
    "ported": "not_ported",
    "roaming": {"status": "unknown"},
    "ip_warnings": "unknown",
    "caller_name": "Wile E. Coyote",
    "last_name": "Coyote",
    "first_name": "Wile",
    "caller_type": "consumer"
}

Business example

{
    "status": 0,
    "status_message": "Success",
    "lookup_outcome": 1,
    "lookup_outcome_message": "Partial success - some fields populated",
    "request_id": "27c61a46-5b4a-4e80-b16d-725432559078",
    "international_format_number": "14155550101",
    "national_format_number": "(415) 555-0101",
    "country_code": "US",
    "country_code_iso3": "USA",
    "country_name": "United States of America",
    "country_prefix": "1",
    "request_price": "0.04000000",
    "remaining_balance": "10.000000",
    "current_carrier": {
        "network_code": "US-FIXED",
        "name": "United States of America Landline",
        "country": "US",
        "network_type": "landline"
    },
    "original_carrier": {
        "network_code": "US-FIXED",
        "name": "United States of America Landline",
        "country": "US",
        "network_type": "landline"
    },
    "valid_number": "valid",
    "reachable": "unknown",
    "ported": "not_ported",
    "roaming": {"status": "unknown"},
    "ip_warnings": "unknown",
    "caller_name": "ACME Corporation",
    "caller_type": "business"
}