API - Get Contact ID by Email Address

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API - Get Contact ID by Email Address



I'm trying to modify specific users' subscribed lists. The problem is that I don't have their Contact ID, just their email address and other personal information. Is there a way using the API to retrieve their Contact ID by email address to update that users' subscribed lists?


If I try to add the user to Contacts, the API comes back with an error that the user already exists, and in the error message, it has the users' Contact ID. I can parse the ID from the string but doesn't feel reliable, and I was hoping the API had an actually way to retrieve the Contact ID in a better / more reliable manner.


Hello AlexM760,


Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.


To get V3 API contact IDs, you’ll want to make a GET call to the Contacts endpoint:

GET https://api.cc.email/v3/contacts


If you are looking for the contact ID of a specific email address, you can add that as a parameter like so:

GET https://api.cc.email/v3/contacts?email=email@domain.com


You can make this call through your platform, or you can just use our V3 API tester which I have linked below. You'll need to be logged into the account that you are retrieving contact data from when using the tester.


V3 API tester: GET Contacts Collection


Please have a look and let us know if you have any other questions!


Courtney E.
API Support Specialist

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