Merge two HubSpot CRM records of the same object type via API
domain: developers.hubspot.com · 5 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Identify the primary record to keep and the record to merge away, both of the same object type (contacts, companies, deals, tickets, and other supported objects including custom objects).
Send POST /crm/v3/objects/{objectType}/merge with body {"primaryObjectId": "<id to keep>", "objectIdToMerge": "<id to merge away>"}.
Expect a merged SimplePublicObject response with a new record ID — the original IDs still resolve via the "Merged [record] IDs" property.
Confirm associations after merging: associated records from both source records appear on the merged record, and for companies, the primary record's "Primary" association label takes priority.
Understand the merge is irreversible before calling the endpoint.
Known gotchas
The path is versioned as v3 with a fixed /merge suffix — it is not date-versioned (there is no /crm/objects/2026-03/... path).
Records cannot be merged once involved in a combined total of 250+ merges, and company merges can fail in parent-child relationship loop scenarios.
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