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How to Improve Retention with SPF/DKIM for Dunning Emails

Only 0.022% of Churn Buster emails get marked as spam.That’s 1 complaint for every 4,584 emails sent. Not bad!

But emails can end up in Spam folders even if they aren’t marked as spam. And it happens more often than you’d think. It’s absolutely critical to get in front of customers when payments fail.

Setting up SPF/DKIM records will build trust, improve deliverability and help you get paid.


SPF (Sender Policy Framework) is an email validation system designed to detect phony emails.

It lets email receivers verify that Churn Buster is authorized to send email for your domain. Spam and phishing emails often use forged “from” addresses, so having a published SPF record in your DNS is a great way legitimize your email sends—and avoid Junk and Spam folders.


DKIM (DomainKeys Identified Mail) is a way to validate that Churn Buster dunning emails are authentic.

Emails are signed using a private key when sent, and validated by the receiver using a public key that is in DNS. So email recipients can verify that the email was not altered while en route.

DKIM also is a way for ISPs to track your domain’s sending reputation over time. By using DKIM you’ll build a reputation for your domain, which will benefit you with all email sends via your server.


Churn Buster is a white label service, so emails are sent on the behalf of the companies we partner with with no mention of Churn Buster. We even host card update pages on the sending company’s domain—more work to set up, but infinitely worth the gain in credibility by not sending customers to a 3rd party website.

Setting up DKIM and SPF records is another step towards a frictionless card update experience when payments fail—a huge benefit to any growing Saas or subscription company.

Already using Churn Buster? Contact your account manager to set up SPF/DKIM records for your account.