What is domain reputation?
Domain reputation is a score that ISPs (Gmail, Outlook, Yahoo) assign to your sending domain based on your email sending history. It's the single biggest factor in whether your emails reach the inbox or land in spam.
Unlike IP reputation, which is tied to the server sending your email, domain reputation follows your domain everywhere. If you switch email providers, your domain reputation comes with you.
How ISPs calculate domain reputation
ISPs track these signals for every domain that sends email through their systems:
- Complaint rate — the percentage of recipients who click "Report Spam." This is the most damaging signal. Keep it below 0.1%.
- Bounce rate — how many of your emails fail to deliver. High bounce rates signal poor list hygiene.
- Spam trap hits — sending to recycled or pristine spam traps is a strong negative signal.
- Engagement — open rates, click rates, and replies. Gmail heavily weights positive engagement.
- Authentication — SPF, DKIM, and DMARC pass rates. Failing authentication is an immediate red flag.
- Volume consistency — sudden spikes in volume from a domain trigger scrutiny.
How to check your domain reputation
- Google Postmaster Tools — free, shows Gmail-specific domain reputation (High/Medium/Low/Bad)
- Microsoft SNDS — Outlook/Hotmail reputation data
- Sender Score (by Validity) — 0-100 score based on sending behavior
- Talos Intelligence (Cisco) — reputation lookup by domain
- MXToolbox — blacklist monitoring and domain health checks
Building reputation from zero
New domains start with neutral (not good) reputation. Here's how to build it:
- Set up SPF, DKIM, and DMARC before sending any email
- Warm up gradually — start with 50-100 emails/day to engaged recipients
- Double weekly volume over 4-8 weeks
- Only send to confirmed, opted-in recipients during warmup
- Monitor bounce and complaint rates daily
- Use a dedicated subdomain for marketing email to isolate reputation
See our domain warmup guide for a detailed schedule.
Protecting existing reputation
- Remove hard bounces immediately and permanently
- Honor unsubscribes within 24 hours (legally required in most jurisdictions)
- Segment your list — don't send marketing email to unengaged recipients
- Use double opt-in for new subscribers
- Monitor Google Postmaster Tools weekly
- Set up alerts for bounce rate spikes and complaint rate increases
- Never buy or rent email lists
Recovering damaged reputation
If your domain reputation has been damaged:
- Stop all marketing/campaign email immediately
- Continue sending only critical transactional email (password resets, receipts)
- Aggressively clean your list — remove anyone who hasn't engaged in 90 days
- Fix any authentication issues (SPF/DKIM/DMARC failures)
- Check and resolve any blacklist listings
- Gradually reintroduce marketing email to your most engaged segment only
- Recovery typically takes 2-4 weeks for moderate damage
Domain reputation with RelayPost
RelayPost helps protect your domain reputation with:
- Automatic bounce and complaint suppression — bad addresses are removed before they damage your reputation
- Real-time delivery monitoring on the deliverability dashboard
- DKIM/SPF configured automatically during domain verification
- Webhook notifications for bounces and complaints
Related guides
Frequently asked questions
What is email domain reputation?
Email domain reputation is a score ISPs assign to your sending domain based on your email sending behavior. It determines whether your emails land in the inbox, spam folder, or get rejected entirely. Unlike IP reputation, domain reputation follows your domain across any sending infrastructure.
How do I check my domain reputation?
Use Google Postmaster Tools for Gmail reputation data. Microsoft SNDS provides Outlook data. Third-party tools like Sender Score and Talos Intelligence also provide reputation insights. RelayPost's deliverability dashboard shows reputation indicators in real time.
How long does it take to build domain reputation?
A new domain starts with neutral reputation. Building positive reputation takes 4-8 weeks of consistent, clean sending with low bounce and complaint rates. Damaging reputation can happen in days with a single bad send.
Can I recover a damaged domain reputation?
Yes, but it takes time. Stop sending to unengaged recipients, clean your list aggressively, fix authentication issues, and gradually rebuild with engaged recipients only. Recovery typically takes 2-4 weeks for moderate damage, longer for severe cases.
Protect your sender reputation
RelayPost handles suppression, authentication, and monitoring automatically.
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