Short answer

HubSpot's KB: with multiple addresses connected, set a default used for new one-to-one emails. It doesn't apply to replies or inbox and help desk emails.

1. In HubSpot

The relevant screen in my demo portal.

Personal Email preferences with Connect email account, Add email alias, and Manage email signatures highlighted — Connect email account (1), Add email alias (2), and Manage email signatures (3).

2. Worth knowing

You can still change the From on each email.

3. Related

Inbox setup and sending as owner.

Sources

HubSpot Community question: Changing the default send from email address and name
HubSpot Knowledge Base: Edit the default From address

Change your default From address for one-to-one emails

Short answer

1. In HubSpot

2. Worth knowing

3. Related

Sources

New field notes by email

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