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API - contacts are getting dropped

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API - contacts are getting dropped

There are 10315 contacts to be uploaded to the constant contact system.

Program is batching the contacts with a batch size of 500 and callng the api in a loop. Our log file shows sending 10315 contacts in the api calls.

API calls are success with no errors, but few contacts are not getting added to the constant contact system.


Out of 10315, constant contact system accepted 10156 contacts. Very difficult to troubleshoot which contacts are getting dropped.

Why these contacts are getting dropped...









After reviewing that data that you emailed to us for your import, the issue here is that there are only 10156 unique email addresses being sent to Constant Contact, even though you have 10315 contact records. This is caused by having multiple contacts that contain the same email address, which our system wil automatically deduplicate.


The ideal way to easily be able to account for this is to de-duplicate the email addresses before you upload to Constant Contact so that you know the correct number of contacts in advance.


Please let me know if you have any questions!



Elijah G.
API Support Engineer
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