Does DMARC Digests collect reports for subdomains?

If you’re using the default DMARC record we provided for your domain, we’re already collecting DMARC reports for emails sent from subdomains. Those emails will be included in the reports you see for your main domain. There is not a filter to specifically check subdomain reports, so if you have a lot of data that makes it difficult to single out your subdomain sends, you may find it beneficial to track your subdomain separately.

The DMARC policy for emails sent using subdomains can be specified using the sp tag in your DMARC record.

Tracking sub-domains separately

If you’d like to monitor who’s sending emails from a specific subdomain, add it as a new domain in DMARC Digests and follow the instructions to set up a DMARC record for the subdomain. We’ll then process DMARC reports for the subdomain separately to any reports we receive for your main domain, allowing you to see just the sources sending using that subdomain.

When a mail server receives a message, it extracts the domain in the From address and tries to find a DMARC policy for that domain. For emails sent from a root domain, the mail server will look for a DMARC policy at _dmarc.yourdomain.com. When an email is sent from a subdomain, it first looks for a DMARC policy specific to the subdomain (e.g. _dmarc.subdomain.yourdomain.com). If this isn’t found, it will fall back to using the DMARC policy for the root domain.