Your Best Dunning Email Is Worthless in the Spam Folder

A crucial aspect of billing recovery that often fails is the dunning email, which is sent when a customer's payment has failed. This email, however, frequently ends up in the spam folder due to its subject line and content, which are perceived as suspicious. The retry logic for dunning emails is flawless, yet the customer never receives the message, rendering the recovery system ineffective.

The issue lies in deliverability, which is a concern unique to dunning emails as opposed to regular product emails. Dunning emails contain language related to money, failed payments, and card updates, all of which are red flags for spam filters and cautious users. Furthermore, these emails are primarily sent to customers who have not engaged with the product in a long time, further harming the email sender's reputation.

Each time a dunning email is not opened, the likelihood of it being filtered increases, creating a compounding effect. To address this, several fixes are required, primarily involving infrastructure adjustments. Sending billing emails from a dedicated subdomain can help maintain a separate reputation from marketing emails. Proper authentication, including SPF, DKIM, and a DMARC policy enforced rather than set to monitor-only, is essential.

The sender's name and address should remain consistent with the customer's initial signup information. The card-update link should be hosted on the primary domain, not a shortened URL, and subject lines should be straightforward and bank-like, such as "Your payment didn't go through."

Instrumentation is crucial for tracking the performance of dunning emails. Monitoring delivery, bounces, and spam complaints per send, rather than per month, provides more accurate insights. A hard bounce, indicating an invalid email address, should immediately redirect the account to alternative channels and cease further email attempts. Soft bounces, caused by temporary server issues or full mailboxes, should be retried briefly before following the same course of action.

Billing suppression lists, used to track permanently unresponsive email addresses, must be kept separate from marketing suppression lists and reviewed regularly. Each address on this list should be treated as a mystery, warranting a human review, as a mistyped domain can often be the root cause. Recovery systems are typically measured by their retry intelligence, but the email itself plays a vital role in the recovery process. Its authentication, timing, and plain-spoken copy are as important as the retry mechanism itself.