Thread Discussion

Hello devs,
I’m building a data migration pipeline using HubSpot’s Imports API, importing three CSV files: Contacts, Companies, and Deals.
Each file contains an entityId field used to associate records across objects:

The import successfully sets up the relationships:

However, I’m running into an issue where existing Companies and Deals are being duplicated instead of being matched to existing records.
Contacts are deduplicated as expected, likely because the email field is recognized as a standard unique identifier.
But for Companies and Deals, even though I’m using entityId consistently and associating correctly across all files, it seems the Imports API doesn’t deduplicate them — it creates new records every time.
Questions:

Thanks