I have recently noticed HubSpot allowed alternative unique id’s to be created for contacts. While it is possible to use this alternative id with the batch read api, when importing contacts using the new alternative unique identifier, I am receiving an “Unknown Error” on all of the rows. I’ve then tried to use the import feature to import deals and associating them to the contacts, but the system doesn’t recognise the contact’s new alternative unique identifier as a valid identifier, but only recognises the “email” and the record ID
The unique ID does not work for contacts according to the knowledge base: Custom property that requires unique values(companies, deals, tickets, and custom objects only): if you’ve created a property that requires unique values, you can use the property as a unique identifier in your import files.
I think this might be a newer feature which isn’t handled yet in the knowledge base. It looks like contacts does allow for custom uniqie identifiers now, but not all of the different HubSpot features accomodate for it yet. I think it is best to just wait for the feature to be fully implemented across HubSpot since it is relatively new
Alex from the import/export team here. Just wanted to pop in to say that you can in fact now use any contact property that requires unique property validation within import as a unique ID used to find existing records, update/dedupe them.