Check why HubSpot contacts keep duplicating
First identify the creation path and the unique identifier it uses.
HubSpot documents contact matching by email, but a CSV without email or another identifier can create a new record for every row. Similar display names are not enough.
Work through the setup
- Identify the source. Find whether the duplicates came from manual creation, forms, imports or a connected app. Record when they appeared before changing the integration.
- Inspect the mapped identifier. For a contact import, confirm the Email column really maps to the email property or that another supported unique identifier is used. A column called “Email address” in the CSV is not proof of correct mapping.
- Review aliases and existing conflicts. Check primary and secondary addresses. The official documentation calls out special behavior when secondary email and Record ID are combined, so do not normalize aliases blindly.
- Fix the path before cleanup. Test a repeated submission using controlled records. Then decide whether existing duplicates need a separate reviewed merge/cleanup process. Export before irreversible changes.
A worked example
A spreadsheet contains “Name” and “Work email”, but only Name was mapped. Importing it twice can create two sets of contacts rather than updating them. A useful diagnostic is to compare the map used by the import with the current record properties, not just compare the file headers.
What to watch out for
- Two people may share a name; one person may use several email addresses.
- Do not merge records only because a company name matches.
- A rule documented for manual entry may not describe every third-party sync.
Diagnose a pair before a whole database
Compare two suspected duplicates using Record ID, primary email, any secondary email and the source that created each record. The display name alone is a weak identifier. Check whether the apparent duplicate is actually a distinct person or a record created through another import or integration. Preserve the original IDs before making changes. A matching exercise is not authorization to merge every similar-looking name; start with a reviewed sample and the documented deduplication rules.
Sources and evidence
- Deduplicate records in HubSpot (read November 7, 2026)
- Export your records (read November 7, 2026)
Common checks
Are companies created by API deduplicated by domain?
HubSpot explicitly says company API creation is not deduplicated by Company domain name. Do not extend the contact email rule to every object.
Published November 7, 2026. Sources last read November 7, 2026. Send a correction.