How I got my business emails through spam filters with SPF, DKIM, and DMARC

SPF, DKIM, and DMARC are DNS records that protect a domain and help keep emails out of junk. Many deliverability problems come from missing or incorrect authentication rather than email content. SPF verifies that the sending server is authorized for the domain. DKIM adds a cryptographic signature to outgoing messages to confirm they were not altered in transit. DMARC combines the results by publishing a policy for what receiving servers should do when checks fail and by routing authentication reports back to the domain owner. Gmail and Yahoo enforced these requirements for bulk senders starting in February 2024, and Microsoft followed for Outlook.com, Hotmail, and Live.com in May 2025, making setup necessary.

"There are a few reasons this could happen that don't always have to do with the contents of your emails. Most commonly, your domain may not be authenticated, which gives receiving mail servers all the reason they need to quietly file your messages away in the spam folder. I've seen this catch people off guard more often than you'd expect, including teams with genuinely good email content."

"Thankfully, there's an easy fix involving three DNS records called SPF, DKIM, and DMARC. Together, they prove to the internet that your emails are legitimate. They also protect your domain from being hijacked by cybercriminals so they can impersonate you in emails. If you haven't set these up yet, they are no longer optional."

"Each of the three protocols addresses a different weak point in email authentication. SPF verifies that the server sending your email is authorized to do so. DKIM adds a cryptographic signature to your outgoing messages, confirming they haven't been altered in transit. DMARC ties the two together by publishing a policy that tells receiving servers what to do when either check fails, and routes authentication reports back to you."

"You genuinely need all three. SPF alone can't stop someone from forging the "From" address your recipient sees in their inbox. DKIM alone won't catch"

Read at ZDNET