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Custom Field limitation - Is there a workaround?


Custom Field limitation - Is there a workaround?

Hello and Good Day,


I've recently tried Constant Contact and its APIs as part of a requirement of one of my clients. During this process my client and I needed to make custom fields to map over to our in-house CRM via your APIs.


The issue that we came across was the amount of custom fields that we could make (only 15) which was very limited and constricting.


My client has heard that a new version that should be available very soon that may offer a different solution to our issue >>.Something called “tags”???


Q1. Are there any workarounds using the current version of the API?

Q2. If there are no workarounds, what are the other options to attain the same end result (to be able to create an undefined amount of custom fields) ?

Q3. What are these "tags" and can they be utilized as a solution to my current problem?


Thank you very much,

Piscoso, Martin



Thank you for reaching out to Constant Contact API Support.

Because our current API was built for our previous contacts system, there are still some limitations to our API's contacts features. Previously, we had a maximum of 15 custom fields, each limited to 50 characters. Tags are also a new feature that is not currently supported within our API. We are working on a new API version which will have the ability to

What are you looking to do with this information once you have it added to your contacts? I may be able to provide you with a workaround.

Please let me know if you have any other questions!

David B.
Tier II API Support Engineer

Hello and Good Day,


I went back to my client and am waiting on what they'll give me about the issue with the limits on custom fields. I'll be sure to message you with the use-case once I have it.


Thank you very much.

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