What subdomain delegation for email vendors are#
Subdomain delegation gives each third-party sender its own subdomain (for example news.example.com for the ESP, help.example.com for the helpdesk) with dedicated SPF, DKIM, and DMARC records, so each vendor's reputation and configuration are isolated.
Why it matters#
One SPF record cannot hold every vendor without exceeding the lookup limit, and one shared domain means one vendor's mistakes damage everyone's placement.
What Brevo handles#
Most platforms, including Brevo, generate the records or settings you need under a domain authentication or sending settings page, and expose bounce and complaint data in reports. Confirm the exact location in Brevo's current documentation.
What you still own#
- List every vendor that sends as your brand.
- Assign each a subdomain and delegate DNS or publish its records directly.
- Publish SPF and DKIM per subdomain using the vendor's values.
- Set the organizational DMARC record with sp= to cover all subdomains.
Common mistakes#
- Delegating the whole zone to a vendor via NS records, giving them control over more than mail.
- Forgetting sp= in DMARC, leaving delegated subdomains unenforced.
Frequently asked questions#
Does using a subdomain hurt brand recognition?
The visible From can still show your brand name; recipients rarely notice the subdomain, and providers reward the isolation.
Does Brevo set up subdomain delegation for email vendors automatically?
Brevo provides the values and some checks, but publishing DNS, aligning domains, and monitoring results remain your responsibility.