Email Deliverability and Domain Reputation After a Spike in Bounces
A B2B SaaS company sends a weekly newsletter to 200,000 subscribers. Last month, they imported a list of 50,000 leads from a trade show without double opt-in. Since then, their bounce rate increased from 2% to 12%, and spam complaints rose from 0.1% to 0.5%. Their sender score dropped from 90 to 70. The marketing team wants to send another newsletter next week to the full list. They use Braze and have a dedicated IP. The goal is to recover deliverability and avoid being blacklisted.
1. What immediate actions should the team take before sending the next newsletter?
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First, stop sending to the entire list. Segment the list: separate the 50,000 imported leads from the original 200,000. For the imported leads, send a re-permission email (double opt-in) to only those who haven't bounced or complained. Remove hard bounces and complainers immediately. For the original list, send only to engaged users (opened in last 90 days) for the next send. Second, implement a sunset policy: suppress users who haven't engaged in 6 months. Third, reduce send volume: send the next newsletter in batches (e.g., 20,000 per day) to warm up the IP gradually. Fourth, monitor sender score daily. Fifth, ensure authentication (SPF, DKIM, DMARC) is set up. The key is to stop sending to unengaged and imported users, clean the list, and slowly rebuild reputation. Sending to the full list again would worsen the score and risk blacklisting.
2. How would you measure the recovery of deliverability and what long-term changes would you make?
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Measure deliverability by tracking bounce rate (target <2%), spam complaint rate (target <0.1%), and sender score weekly. Also monitor open rate and click rate to ensure engagement. Use Braze's deliverability reporting. Long-term: implement double opt-in for all new sign-ups, never import lists without permission, and use a sunset policy to remove unengaged users after 6 months. Segment by engagement and send re-permission campaigns to win back inactive users. Also, set up a feedback loop with the ISP to receive complaints. Regularly clean the list. Train the team on list hygiene. The goal is to maintain a sender score above 85. After recovery, gradually increase send volume while monitoring metrics. Consider using a separate IP for marketing vs. transactional if volume grows.