Choose Which Domain Sends Which Emails

If you have more than one dedicated sending domain, assign specific domains to specific email types instead of leaving it to chance.

Assigning domains by email type

Settings > Email Services > Dedicated Domain and IP > Domain Configuration — assign a domain to Workflows, Email campaigns, Bulk action emails, or Manual one-on-one emails independently. Unassigned sends fall back to your default.

Why you'd split things up

Spreads high volume across multiple domains, protecting your best one from overuse. Set percentage-based distribution for load balancing; calendar emails can split across up to five domains.

At send time, a Sender Domain dropdown lets you pick one explicitly or choose All Domains to rotate automatically. Locked in once sent or scheduled.

Setting a fallback identity

Under Set Headers on a domain, define a fallback From Name/Email used automatically if a send's sender doesn't align with that domain's authentication — prevents outright failure.