What is Sender Score?
Sender Score is a reputation metric, originally created by Return Path (now Validity), that rates your email sending reputation on a scale of 0 to 100. Think of it as a credit score for your email domain or IP address. The higher your score, the more likely your emails are to reach recipients' inboxes.
How Sender Score is Calculated
Your Sender Score is determined by analyzing 30 days of sending behavior, including:
- Complaint rates: How often recipients mark your emails as spam.
- Infrastructure quality: Proper authentication (SPF, DKIM, DMARC).
- Unknown user rates: How many emails bounce due to invalid addresses.
- Spam trap hits: Sending to addresses designed to catch spammers.
- Sending volume and patterns: Consistency and predictability of your email behavior.
Score Ranges
- 80-100: Excellent, strong inbox placement rates.
- 70-79: Good, most emails reach the inbox.
- 50-69: Fair, some deliverability issues; needs attention.
- Below 50: Poor, significant spam folder placement; urgent action needed.
Why Sender Score Matters for Outbound
A low Sender Score directly impacts your ability to run effective cold email campaigns. Email providers use reputation signals (including but not limited to Sender Score) to filter incoming mail. A score below 70 can reduce inbox placement by 20-40%, effectively wasting a large portion of your outbound effort.
Improving Your Sender Score
- Clean your lists: Remove invalid and unengaged contacts regularly.
- Authenticate properly: Ensure SPF, DKIM, and DMARC are correctly configured.
- Monitor complaints: Keep spam complaint rates below 0.1%.
- Warm up gradually: Never spike sending volume from a new domain.
- Segment and target: Better targeting = better engagement = better scores.
How FlowStrata Monitors Sender Score
FlowStrata tracks sender reputation metrics across all client domains in real-time. We set up automated alerts when scores drop below safe thresholds and proactively adjust sending patterns to maintain optimal deliverability.