Rate this page:

Lookup v1 API

Version 2 of the Lookup API is now available! Lookup v2 has an improved developer experience and exciting features, such as Twilio Regions support and these new data packages:

  • Line Type Intelligence: Get the line type of a phone number including mobile, landline, fixed VoIP, non-fixed VoIP, toll-free, and more.
  • SIM Swap: Get information on the last SIM change for a mobile phone number.
  • Call Forwarding: Get the unconditional call forwarding status of a mobile phone number.
  • Identity Match: Get confirmation of ownership for a mobile phone number by comparing user-provided information against authoritative phone-based data sources.

You are currently viewing Version 1 content. Lookup v1 will be maintained for the time being, but any new features and development will be on v2. We strongly encourage you to do any new development with Lookup v2. Check out the migration guide or the API v2 Reference for more information.

The Lookup API provides a way to retrieve additional information about a phone number. Lookup currently supports the following types of data.

  • Region-specific number formatting and validation
  • Carrier Information
  • Caller Name

You can specify one or more types of information you would like to purchase in the request, check the Lookup Product Page for pricing information.


All URLs referenced in the documentation use the following URL.{PhoneNumber}

The Twilio REST API is served over HTTPS. To ensure data privacy, unencrypted HTTP is not supported.

{PhoneNumber} is the phone number you are requesting information about. Phone numbers can be specified either in national formatting or in standard E.164 format. If providing a number in local national format, please also specify the country as an optional parameter. If no country is provided, this will default to US.


HTTP requests to the REST API are protected with HTTP Basic authentication. To learn more about how Twilio handles authentication, please refer to our security documentation. In short, you will use your Twilio account SID as the username and your auth token as the password for HTTP Basic authentication.

curl -G{PhoneNumber} \

You can find your account SID and auth token in your console.

To learn more about authentication and interaction with the Twilio REST API, check out our documentation for requests to the API and Twilio's response.

Phone number lookup


Returns phone number information matching the specified request. Formatting information is standard. Carrier, Caller Name, and phone number type information can be requested, in addition to using Add-ons to access 3rd party data sources.

Query Parameters

The following basic GET query string parameters allow you to specify the phone number you want information about and the types of information you’d like:

Parameters in REST API format
get phone_number PII MTL: 30 DAYS

The phone number to lookup in E.164 format, which consists of a + followed by the country code and subscriber number.

get string PII MTL: 30 DAYS

The ISO country code of the phone number to fetch. This is used to specify the country when the phone number is provided in a national format.

get string[] Not PII

The type of information to return. Can be: carrier or caller-name. The default is null. Carrier information costs $0.005 per phone number looked up. Caller Name information is currently available only in the US and costs $0.01 per phone number looked up. To retrieve both types on information, specify this parameter twice; once with carrier and once with caller-name as the value.

get string[] PII MTL: 30 DAYS

The unique_name of an Add-on you would like to invoke. Can be the unique_name of an Add-on that is installed on your account. You can specify multiple instances of this parameter to invoke multiple Add-ons. For more information about Add-ons, see the Add-ons documentation.

get prefixed_collapsible_map<AddOns> Not PII

Data specific to the add-on you would like to invoke. The content and format of this value depends on the add-on.

Resource Properties

The following properties are always returned:

  • Only possible numbers (for a given region, using length and prefix information) will return formatting results. If you attempt to lookup a phone number which is not valid, you will receive an HTTP 404 error.
  • Machine to machine (M2M) phone numbers are not supported in Lookup and will return an HTTP 404 error.
Resource Properties in REST API format

The name of the phone number's owner. If null, that information was not available.


The ISO country code for the phone number.

phone_number PII MTL: 30 DAYS

The phone number in E.164 format, which consists of a + followed by the country code and subscriber number.


The phone number, in national format.

object Not PII

The telecom company that provides the phone number.


A JSON string with the results of the Add-ons you specified in the add_ons parameters. For the format of the object, see Using Add-ons.

url Not PII

The absolute URL of the resource.

  • Access to Canada carrier information requires special approval. Please read this support article to learn more. Querying a Canada phone number without access will return a 60101 error.
  • Toll free numbers do not return carrier data, but will return a valid HTTP response.

The following additional properties are returned if you requested carrier information in your GET request:

Name Description
MobileCountryCode The three digit mobile country code of the carrier, used with the mobile network code to identify a mobile network operator.
MobileNetworkCode The two-three digit mobile network code of the carrier, used with the mobile country code to identify a mobile network operator (only returned for mobile numbers).
Name The name of the carrier; often subject to change.
Type The phone number type. Possible values are landline, mobile, or voip. See 'Phone Number Types' below for more information.
ErrorCode The error code, if any, associated with your request.
Phone Number Types

The following are the possible values for the 'Type' property.

Type Description
landline The phone number is a landline number; generally not capable of receiving SMS messages.
mobile The phone number is a mobile number; generally capable of receiving SMS messages.
voip An internet based phone number that may or may not be capable of receiving SMS messages. For example, Google Voice. Returned for U.S. numbers only.
null The phone number is valid but no information was returned from our data providers (see limitation for Canada numbers).

Caller name information

Caller name information is sourced through CNAM and only available for phone numbers owned by carriers in the US. We recommend testing the coverage rate of this lookup with your specific dataset of phone numbers.

The following additional properties are returned if you requested caller name in your GET request:

Name Description
CallerName String indicating the name of the owner of the phone number. If not available, this will return null.
CallerType String indicating whether this caller is a business or consumer. Possible values are BUSINESS, CONSUMER. If not available, this will return null.
ErrorCode The error code, if any, associated with your request.

Caller name lookups for US numbers are billed per lookup, even if data is not be available. Requesting Caller name lookups for non-US will return null values and will not be billed.

Loading Code Sample...

        Carrier Lookup with E.164 Formatted Number

        Loading Code Sample...

              Carrier Lookup with National Formatted Number

              Loading Code Sample...

                    Caller Name Lookup

                    Using Add-ons with Lookup

                    Lookup also supports Twilio Add-ons, enabling you to retrieve information from a multitude of 3rd party data sources, available via the Twilio Marketplace.

                    You can add Lookup supported Add-ons by visiting the Twilio Console to enable the Add-on. Once it has been enabled, make sure you have 'Lookups' selected in its configuration:

                    Console screenshot showing that &#x27;Lookups&#x27; is checked for the ekata_phone_valid Add-On

                    When you use AddOns, you can pass additional parameters to the Add-on(s):

                    Name Description
                    AddOns.addon_name.param_name Optional. Passes additional data to the Add-on at request time. See Add-on documentation in Console to identify if the Add-on requires additional parameters.

                    Examples with Add-ons

                    Loading Code Sample...

                          Deterministic TCPA Compliance with Lookup and the Payfone Add-on

                          Loading Code Sample...

                                Detect Robocallers with Lookup and Nomorobo Spam Score Add-on

                                Rate this page:

                                Need some help?

                                We all do sometimes; code is hard. Get help now from our support team, or lean on the wisdom of the crowd by visiting Twilio's Stack Overflow Collective or browsing the Twilio tag on Stack Overflow.

                                Loading Code Sample...

                                      Thank you for your feedback!

                                      Please select the reason(s) for your feedback. The additional information you provide helps us improve our documentation:

                                      Sending your feedback...
                                      🎉 Thank you for your feedback!
                                      Something went wrong. Please try again.

                                      Thanks for your feedback!