← Glossary
Sender Reputation
A score ISPs assign based on your sending history and subscriber engagement.
Sender reputation is an ISP-calculated score determining whether your emails reach the inbox. Factors: bounce rates, spam complaints, engagement (opens/clicks), sending volume consistency, authentication setup, and list age. Reputation is tied to your sending domain and IP. New senders start with neutral reputation — consistent good engagement builds it; spam complaints and bounces destroy it quickly. Custom domain sending builds reputation on your brand, not a shared platform domain.