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Deliverability 2 min read
Last updated: May 2026

What is Email Reputation?

A score assigned to your sending domain and IP address by mailbox providers that determines whether your emails reach the inbox.

What is Email Reputation?

Email reputation (also called sender reputation) is the trust score that mailbox providers assign to your domain and IP address based on your sending history. It's the cumulative result of every email you've ever sent, bounces, complaints, engagement, authentication, and volume patterns all factor in.

Think of it like a credit score for email. A high reputation means your emails are trusted and delivered to inboxes. A low reputation means your emails are filtered to spam or rejected entirely.

Why Email Reputation Matters for Outbound

Email reputation is the single biggest factor determining whether your cold emails reach prospects. You can have perfect copy, impeccable targeting, and flawless personalization, but if your reputation is damaged, none of it matters because your emails never reach the inbox.

Key Components

  • Domain reputation: Your sending domain's trust score (checked via Google Postmaster Tools)
  • IP reputation: The trust score of the IP address your emails originate from
  • Engagement metrics: Open rates, reply rates, and click-through rates signal positive reputation
  • Complaint history: Spam reports and unsubscribe rates signal negative reputation
  • Bounce history: High bounce rates indicate poor list quality
  • Authentication status: Proper SPF, DKIM, DMARC improve reputation signals

Reputation Scale (Google Postmaster)

  • High: Emails consistently reach the inbox
  • Medium: Most emails delivered, but some filtering occurs
  • Low: Significant spam filtering applied
  • Bad: Nearly all emails sent to spam or rejected

Common Mistakes

  • Sending too fast too soon: Volume spikes on new domains trigger immediate reputation damage
  • Neglecting warmup: New domains need 2-4 weeks of gradual volume increase
  • Ignoring engagement signals: Low engagement tells providers your emails aren't wanted
  • Sharing IPs carelessly: On shared IPs, another sender's bad behavior damages your reputation

How FlowStrata Protects Email Reputation

FlowStrata takes a reputation-first approach to every outbound campaign. We warm up every domain gradually, monitor reputation through Postmaster Tools daily, maintain strict volume limits per inbox, and immediately pause sending if reputation indicators decline. Our infrastructure uses dedicated IPs where possible and isolates client sending to prevent cross-contamination.

Related Terms

Complaint Rate

The percentage of delivered emails that recipients report as spam, calculated as...

Domain Reputation

A score assigned to your email domain by inbox providers that determines whether...

Email Deliverability

The ability of outbound emails to successfully reach prospects' inboxes rather t...

Email Warmup

The process of gradually increasing email sending volume from a new or inactive ...

Inbox Placement Rate

The percentage of delivered emails that actually land in the recipient's primary...

Sender Score

A numerical rating (0-100) that reflects the trustworthiness of your email sendi...

Want Us to Handle This For You?

Now you know what Email Reputation means. Let FlowStrata implement it as part of a fully managed outbound engine that books qualified meetings on your calendar.

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