Automated Email Goes to Spam: SPF, DKIM, and DMARC as an Operations Process

If invoices or password resets reach spam, changing message wording alone is not enough. Mail recipients also evaluate sender identity, domain alignment with authentication, reputation, sending rate, and complaints. SPF, DKIM, and DMARC are separate mechanisms that must be coordinated with each other and with the sending provider.

Create a sender inventory: website, invoicing system, CRM, support, and every third party. For each, document sending domain, reply-to address, DNS configuration, owner, and email purpose. That prevents deletion of an essential SPF entry when adding a new service.

After a DNS change, test a real message in several mailboxes, inspect authentication headers, and monitor delivery rate rather than only “sent.” Do not use business email to transmit passwords or sensitive payment data. Technical protection does not replace consent and responsible sending practices.

Source

Google sender guidelines