Short answer

HubSpot's KB: when using a contact-based action in another workflow type, you must add contacts as a data source, and the action updates one contact at a time. The KB lists which contact-based actions are supported.

1. In HubSpot

The relevant screen in my demo portal.

Workflow action search for association showing Create associations, Apply association labels and Update association labels — Create associations (1) and label actions (2).

2. Worth knowing

If a deal has several contacts, decide which one the action should use.

3. Related

Data variables.

Sources

HubSpot Community question: Contact Based Workflows triggered by Webhooks
HubSpot Knowledge Base: Use contact-based workflow actions in other workflow types

Run contact actions from deal or ticket workflows

Short answer

1. In HubSpot

2. Worth knowing

3. Related

Sources

New field notes by email

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