LetsDMARC vs.
Postmastery in 2026

LetsDMARC identified Microsoft 365 and Google Workspace immediately, grouped the changing SendGrid IP pool under a recognizable source, and showed Mailchimp as a separate approved sender. Its result drilldown preserved the aligned DKIM pass on our forwarded sample, but explaining why SPF failed took an extra move into selector and alignment detail. The unknown sender gained useful organization context, while the final owner classification still needed our decision.

Postmastery organized the same traffic around domains, sources, and authentication combinations. The Google Workspace and Microsoft 365 streams were obvious, SendGrid was easy to filter, and Mailchimp needed one confirmation before we treated every IP as approved. Its combination view explained the forwarded SPF failure and surviving DKIM alignment more directly, while the unknown sender remained visibly unresolved until we classified it.

We added the corporate domain, marketing subdomain, and parked domain in one session. LetsDMARC's wizard produced clear record values and treated the parked domain's no-mail posture as a distinct policy case. The unknown sender was visible in the source view, although assigning an owner was manual. For the forwarded sample, we had to combine the SPF result with the aligned DKIM detail before the failure made sense.

Postmastery's automated setup produced a unique reporting record quickly for all three test domains, and the domain-source hierarchy stayed compact. The unknown sender surfaced near the top of the source list after filtering for unrecognized traffic. Its authentication-combination view explained that forwarding broke SPF while aligned DKIM preserved DMARC, so a non-specialist could follow the outcome with less coaching.

During setup, LetsDMARC's instructions covered the reporting record and the later managed DMARC and SPF handoff in a sequence our DNS owner could follow. The export gave us a usable change-ticket attachment, and escalation expectations were clear when we framed the forwarded case as alignment rather than an SPF outage. Parent and child tenant roles also made enterprise onboarding responsibilities concrete.

Postmastery treated support as part of a broader DMARC implementation and deliverability engagement. The policy review was useful for deciding when our primary domain was ready to leave monitoring, and the escalation path reached people who could discuss the SendGrid and forwarding evidence. The tradeoff was scheduling: the DNS handoff and enterprise onboarding plan felt more consultative than self-serve.

LetsDMARC kept the primary domain, marketing subdomain, and parked domain in logical groups, and its parent-child tenant model preserved account separation when we simulated client ownership. Recurring domain-group reports and tenant-specific history supported an MSP handoff without exposing unrelated domains. An enterprise gets useful delegation, while an SMB with one domain has more administration than it needs.

Postmastery worked best when we treated all three domains as one enterprise sending program. Consolidated source views and CSV exports supported recurring reporting, and consultants could turn the evidence into a client-ready policy plan. We did not find an equally explicit MSP workflow for separate client accounts, reusable handoff notes, and delegated ownership, so agencies should verify those requirements during evaluation.