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Deliverability
Sender reputation explained: how to build and protect it
MO
Sender reputation is the invisible score that decides inbox versus spam. You can't see it directly, but you can shape it. Here's how it works and how to protect it.
What it is
Reputation is a trust score mailbox providers assign to your sending domain and IP, built from signals like bounce rate, spam complaints, engagement and sending consistency. A poor reputation means even legitimate mail gets filtered.
The signals that matter most
- Bounce rate — keep it under ~2%.
- Spam complaints — keep them rare.
- Engagement — opens, clicks and replies.
- Consistency — steady volume, no sudden spikes.
List quality is the foundation
Bounces and spam-trap hits damage reputation fastest, and both come straight from unverified lists. Clean the list and you remove the biggest risk at the source.
Repairing a damaged reputation
If your reputation has slipped, pause, clean the list thoroughly, and warm back up slowly — sending to your most engaged contacts first and ramping volume gradually as the signals recover.
See how clean your list really isFree preview of your first 100 contacts — no credit card.
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