Email sender reputation is the trust that mailbox providers assign to your sending domain and IP address, based on how recipients and systems have reacted to your past mail. Complaints, bounces and spam-trap hits lower it. Engagement and consistent sending raise it. Providers do not publish a single score.
What affects sender reputation?
- Spam complaints. The most heavily weighted negative signal.
- Bounces and invalid addresses. See bounce rate guidance.
- Spam-trap hits. Evidence of poor list sourcing or hygiene.
- Engagement. Opens, clicks, replies and moving mail out of spam.
- Consistency. Predictable volume and cadence.
- Authentication. Properly aligned SPF, DKIM and DMARC let reputation attach to your domain.
Is there IP reputation and domain reputation?
Both. IP reputation tracks the sending address and matters most with dedicated IPs. Domain reputation follows your domain across IPs and is increasingly central at Gmail, which means that switching providers does not erase a bad history.
How do you check your reputation?
There is no universal score. Use data from the providers themselves: Google Postmaster Tools for Gmail, and Microsoft's Smart Network Data Services for Outlook.com IPs. Add blocklist checks from the blocklist guide, your platform's complaint and bounce reports and a placement test.
How do you repair a damaged reputation?
- Stop sending to unengaged and risky segments.
- Clean the list and remove hard bounces. See list hygiene.
- Fix authentication and unsubscribe handling.
- Send only to your most engaged contacts at a lower volume.
- Increase volume slowly, following warm-up principles.
- Be patient. Recovery typically takes weeks of consistent, clean sending.
Changing domains is not a fix. Reputation follows behavior.
What does a healthy reputation look like in practice?
Complaints stay rare, hard bounces are removed after each send, a good share of recipients open or click, and volume changes happen in small steps. Trouble signs include delayed delivery at one provider, a sudden jump in spam-folder placement and rejection messages that mention reputation or policy.
Where does this fit in your overall plan?
Reputation is the output of everything else. The checklist in improving email deliverability and the habits in best practices are what move it. For background, start with the deliverability overview.
Frequently asked questions
What is a good sender reputation?
Providers use their own scales. In Postmaster Tools, Google labels domain reputation from bad to high, and you should aim for the top tiers.
How long does it take to build sender reputation?
It builds over weeks of consistent sending with good engagement. There is no fixed timeline.
Does sender reputation reset when I change my IP?
IP reputation resets, but domain reputation stays attached to your domain, so changing IP does not erase a bad history.
Can one bad campaign ruin my reputation?
A very bad campaign, with high complaints or a purchased list, can do real damage. Recovery takes time.