Email Glossary

Sender Reputation

Sender reputation is a score that email providers assign to your sending IP address and domain based on your email sending behavior. A good reputation means more emails reach the inbox; a poor reputation means spam folder or blocks.

IP vs Domain Reputation

IP Reputation Tied to the IP address sending your emails. Shared IPs pool reputation across all senders. Dedicated IPs give you sole control but require warmup.

Domain Reputation Tied to your sending domain regardless of IP. This is increasingly important as ISPs focus more on domain signals. You carry your domain reputation even when switching providers.

Gmail, Microsoft, and Yahoo now weight domain reputation heavily. A good IP won't save a bad domain reputation.

What Affects Reputation

Positive factors:

  • ●High open and click rates
  • ●Low spam complaints
  • ●Low bounce rates
  • ●Consistent sending patterns
  • ●Proper authentication (SPF, DKIM, DMARC)
  • ●Recipients adding you to contacts

Negative factors:

  • ●Spam complaints
  • ●Hitting spam traps
  • ●High bounce rates
  • ●Sending to unengaged users
  • ●Blacklist appearances
  • ●Sudden volume spikes

Checking Your Reputation

Google Postmaster Tools Shows reputation for Gmail specifically. Provides domain and IP reputation scores, spam rates, and authentication success.

Microsoft SNDS Smart Network Data Services for Outlook/Hotmail reputation data.

Third-party tools Services like Sender Score, Talos Intelligence, and BarracudaCentral show reputation data and blacklist status.

Check these regularly, especially after large campaigns or changes to your sending.

Rebuilding Damaged Reputation

If your reputation is damaged:

  • ●Stop and assess - Identify what caused the damage
  • ●Clean your list - Remove bounces, complaints, inactive subscribers
  • ●Start small - Only send to your most engaged contacts
  • ●Monitor closely - Watch every metric
  • ●Gradually increase - Like warming up a new domain
  • ●Fix the root cause - Don't just treat symptoms

Recovery takes weeks to months. A new domain may be faster for severe reputation damage.

Related Tools

DNS Checker

Related Terms

Email Deliverability

The ability of your emails to reach recipients' inboxes instead of spam.

IP Reputation

The trustworthiness score assigned to an IP address based on its email sending history.

Email Warmup

Gradually increasing email volume to build sender reputation with ISPs.

Email Blacklist

A database of IPs or domains identified as spam sources that ISPs use to block email.

Frequently Asked Questions

How long does it take to build reputation?
A new domain or IP takes 4-8 weeks of consistent, quality sending to establish a positive reputation. During this warmup period, ISPs learn your sending patterns and engagement rates.
Can I recover from a bad reputation?
Yes, but it takes time and discipline. Clean your list aggressively, send only to engaged users, and gradually rebuild. Severe cases may warrant starting fresh with a new subdomain or domain.
Should I use a shared or dedicated IP?
It depends on volume. Under 100K emails/month, a quality shared IP pool (like Transmit's isolated sending) is fine. Above that, dedicated IPs give you full control but require warmup and consistent volume to maintain.
Get started in minutes

Need help with email deliverability?

Transmit handles authentication, warmup, and reputation isolation automatically.