Postmastery vs.
DMARC-SRG in 2026

Postmastery gave us richer interpretation of Microsoft 365 and Google Workspace traffic after the first DNS records landed. SendGrid and Mailchimp were separated into recognizable sending streams, the unknown support desk sender needed an owner note, and the forwarded mail SPF failure was explained as an authentication edge case rather than a spoof. The product was strongest when a human operator reviewed the output and tied it to enforcement steps.

DMARC-SRG parsed the same aggregate reports cleanly and let us filter by domain, reporting organization, and month. Microsoft 365 and Google Workspace were visible as rows rather than guided source cards, SendGrid and Mailchimp classification depended on our labels, and the SPF pass with visible from mismatch required us to read the raw identifier details. It felt useful for teams comfortable owning the analysis.

Postmastery onboarding for the corporate domain, marketing subdomain, and parked domain had more structure around DNS changes and approved senders. We still had to validate the unknown support desk sender manually, but the workflow made it easier to write a handoff note and explain why the forwarded mail SPF failure should not trigger a panic response.

DMARC-SRG setup took more operational work because we had to configure ingestion, database storage, cleanup, and access. Once running, finding the unknown sender meant filtering by domain and reporting organization, then checking SPF and DKIM result rows ourselves. The forwarded mail SPF failure was visible, but we had to supply the explanation.

Postmastery support expectations matched an enterprise DMARC rollout. DNS handoff steps were clear enough for our primary domain, escalation made sense when the support desk sender needed classification, and the onboarding path gave us a cleaner way to explain policy movement to security and messaging owners.

DMARC-SRG support was the open-source model: documentation, project artifacts, and our own administrator time. That worked for parser setup, but DNS handoff, production escalation, backup planning, and enterprise onboarding all had to be designed around the tool rather than handled inside it.

Postmastery handled account separation and domain grouping better in our test, especially when we split the corporate domain, marketing subdomain, and parked domain for different owners. Recurring reporting was easier to explain to an enterprise audience, but MSP-style client handoff still needed tighter repeatability than we wanted for many small accounts.

DMARC-SRG was a fit for SMB or technical teams that want a low-cost parser and can manage their own hosting. It did not give us native multi-tenancy, account separation, recurring client reports, or handoff notes, so an MSP would need to build those workflows around the product.