Is there a risk of losing contact data or deal history during a HubSpot migration?

The risk of permanent data loss during a well-planned migration is low, but data accuracy issues are common. The most frequent problems are duplicate records from improperly merged data sources, incorrect field mapping that puts values in wrong properties, and lost timestamp accuracy where HubSpot sets the creation date to the import date rather than the original record creation date.

Contact records, company records, and deal data transfer through import tools or API-based migration platforms. The risk points are in the mapping, not the transfer itself. If your source CRM stores "company size" as a range (1-50, 51-200) and HubSpot expects a number, that field corrupts silently unless the mapping rules account for the format difference. Deal history has specific limitations: deals with no associated contact require manual cleanup before import, and open deal amounts may not pull correctly depending on the source system's data structure. Enrollment history for workflows cannot migrate due to HubSpot API limitations, meaning you lose the record of which contacts went through which automation sequences (though the contacts themselves and their properties transfer fine). Mitigating these risks requires a pre-migration data audit, sample test imports before the full transfer, and post-migration verification where you cross-check a representative sample of records against the source system.