How do you find and remove duplicate contacts in HubSpot?

Default's MCP server (beta) has a read-only crm_duplicates_scan tool that lists HubSpot contacts sharing an email and companies sharing a domain, with their record IDs. You then merge each group in HubSpot, and Match Record before every Create Record keeps new duplicates out.

Why does HubSpot create duplicate contacts?

Default keeps its own workflows from adding duplicates by running Match Record on the email before Create Record, so a repeat submission reuses the existing contact. HubSpot deduplicates contacts by email, so a duplicate appears when the same person arrives with a different email or none, such as an import with no email column.

Does Default link new HubSpot contacts to existing companies?

Yes, Default's Match Record node finds the HubSpot company by domain, association, or primary company, and Create Association links the new contact to it. Personal email domains such as gmail.com never match a company, so those contacts stay unlinked or go to enrichment first.

What happens when 2 form fills for the same HubSpot contact overlap?

Default's Match Record and Create Record are separate steps, so 2 runs a second apart can both find no contact and both try to create it. HubSpot keeps the email unique and rejects the second create, Default writes none of its properties, and that run's owner pick does not count as an assignment.

More than fixing HubSpot duplicate contacts

Keep duplicate contactsout of HubSpot

Default checks HubSpot before it creates a contact and links new contacts to the right company.

Request a Demo

Match Record node checking HubSpot for an email before a Create Record node

Match before create

Match Record looks up the email before Create Record runs, so a person HubSpot already has is not created again.

Second form fill from the same email matched to the existing HubSpot contact

Existing record reused

A repeat form fill with the same email reuses the existing contact and keeps its owner.

New HubSpot contact associated with an existing company that shares its domain

Companies matched by domain

New contacts are linked to the HubSpot company that already has their email domain.

Duplicate scan results grouping HubSpot contacts that share an email

Find existing duplicates

A read-only scan groups contacts by email and companies by domain.

Every new contact is checkedagainst HubSpot first

Match Record looks up the email before Create Record runs. If 2 runs for the same email overlap, HubSpot keeps the email unique and rejects the second create, and the existing contact keeps its owner.

Workflow with Match Record on email, a Match branch that keeps the owner, and a No Match branch that creates the contact

HubSpot contacts docs

HubSpot contact matching

Match by email, create only on No Match, and leave known contacts with their owner.

CRM nodes docs

Match record

Find a HubSpot record by its properties, with tiebreakers when several match.

New contacts attach tothe company you already have

Match Record finds the company by domain, association, or primary company, and Create Association links the new contact to that existing record.

Match Record finding a HubSpot company by domain and Create Association linking the new contact to it

Contact to company docs

Contact to company matching

Match by company domain, an existing association, or the primary company, with tiebreakers when a domain has several companies.

CRM nodes docs

Create association

Links the new contact to the matched company in the same run.

Existing duplicates are easy to find

The duplicate scan on Default's MCP server groups contacts by email and companies by domain, so you know exactly what to merge in HubSpot. The scan only reads, and the merge itself happens in HubSpot.

Duplicates docs

Duplicates

Stop new duplicates with Match Record and list the ones you already have.

MCP docs

MCP server

Ask Claude or Cursor to scan your CRM for duplicates through the MCP server, now in beta.

FAQ

Questions about HubSpot duplicate contacts

Default's MCP server (beta) has a read-only crm_duplicates_scan tool that lists HubSpot contacts sharing an email and companies sharing a domain, with their record IDs. You then merge each group in HubSpot, and Match Record before every Create Record keeps new duplicates out.
Default keeps its own workflows from adding duplicates by running Match Record on the email before Create Record, so a repeat submission reuses the existing contact. HubSpot deduplicates contacts by email, so a duplicate appears when the same person arrives with a different email or none, such as an import with no email column.
Yes, Default's Match Record node finds the HubSpot company by domain, association, or primary company, and Create Association links the new contact to it. Personal email domains such as gmail.com never match a company, so those contacts stay unlinked or go to enrichment first.
Default's Match Record and Create Record are separate steps, so 2 runs a second apart can both find no contact and both try to create it. HubSpot keeps the email unique and rejects the second create, Default writes none of its properties, and that run's owner pick does not count as an assignment.

Modern foundations for go-to-market

One platform to manage workflows, enrich records, route leads, and schedule meetings.