SPF, DKIM, and DMARC Explained: Why Your Emails Might Be Going to Spam
These three email authentication standards prove your emails are legitimately from you — without all three properly configured, Gmail and Yahoo increasingly.
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What These Three Things Actually Do
SPF, DKIM, and DMARC are technical records that prove an email genuinely came from your business and wasn't sent by someone impersonating your domain — a form of authentication that email providers increasingly require before trusting your mail.
Each one checks something slightly different: SPF verifies which servers are allowed to send on your behalf, DKIM adds a digital signature proving the message wasn't altered, and DMARC tells receiving servers what to do if a message fails either check.
Why This Has Become Non-Negotiable
Gmail and Yahoo have tightened enforcement significantly — a partially configured or missing setup, which might have been tolerated a couple of years ago, now increasingly means default routing to spam rather than the inbox.
This isn't a one-time setup you can get "close enough" on; these providers now check for syntactically correct, fully functioning configurations, not just the presence of the records.
What to Check on Your Own Setup
Confirm all three are properly configured for every domain and email service you send marketing or transactional email from — free online checking tools can quickly verify whether each one is set up correctly.
If you use multiple email tools (a CRM, a marketing platform, a help desk), each one needs to be properly included in your SPF and DKIM setup, not just your primary email provider.
Get Your Email Authentication Fixed
Appcly can audit and properly configure SPF, DKIM, and DMARC for your business's email sending.
Book a free consultation if your emails have been landing in spam.
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