High Bounce or Complaint Rates in Mailgun

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Mailgun maintains strict thresholds for bounce and complaint rates to ensure the health and reputation of their shared IP pools. If your domain exceeds a 5% bounce rate or a 0.05% complaint rate, your domain may be temporarily disabled. To prevent this, you can monitor your bounce and complaint rates in Mailgun’s reporting dashboard closely. On the other hand, you can follow the steps below to get your domain re-activated if it has been disabled.

Cleaning Up Your Subscribers List

First, use an email validation service like Kickbox to identify and remove invalid or non-existent email addresses. Additionally, Mailgun offers its own email validation service. Regardless of the tool of your choice, you should send only to addresses classified as Deliverable and Risky or equivalent. You may also send to Unknown addresses if your bounce rate is low, but you must never send to those identified as Undeliverable.

Prisma Campaigns allows you to change your customers subscription status and also view a statistical breakdown of the active subscribers by campaign and refine by blast or flow via the campaign’s analysis.

Maintaining a Healthy List

Second, regularly evaluating subscriber engagement by tracking opens and clicks (also available in Mailgun’s reporting dashboard) is a good idea. For subscribers who have not interacted with your emails in six months or more (adjust this threshold as needed), consider removing them from your lists or sending a re-confirmation email to ensure they are still interested in your communications.

Needless to say, your emails need to include a clear unsubscribe link. Remember that legal frameworks like the GDPR and the CAN-SPAM Act require you to provide a way for your subscribers to opt out of your communications. Prisma Campaigns includes the unsubscribe link automatically and provides the communication preferences so that customers may choose what channel, category, and group they want to receive.

What to Do If Your Domain Is Disabled

If your domain has been disabled, contact the Prisma Campaigns support team. You will need to provide proof of the steps you have taken to prevent future bounces and complaints as explained above. As you do so, prepare to explain your process for collecting email addresses and how you ensure people know they are on your mailing lists.

Remember that if your domain exceeds Mailgun’s acceptable thresholds again, it will be subject to disablement in the future.