Sender reputation
📖 3 min readUpdated 2026-04-19
Every sending domain and IP has a reputation score with each email provider. Higher = better inbox placement. Built and lost over time.
Signals that help
- Low bounce rate
- High engagement
- Low complaints
- Consistent volume
- Good content
Signals that hurt
- Spike in volume
- High bounce from bad addresses
- Complaint rates above 0.1%
- Sending to unengaged addresses
Monitoring
- Google Postmaster Tools (Gmail)
- Microsoft SNDS (Outlook)
- Sender Score (general)