Definition
Your sending reputation score represents how trustworthy your email program appears to ISPs. Each major ISP calculates reputation differently, but common factors include complaint rates, bounce rates, engagement rates, authentication compliance, and sending volume consistency.
Factors That Affect Your Score
- Complaint rate: The strongest negative signal — keep below 0.1%
- Bounce rate: High hard bounce rates indicate poor list hygiene
- Engagement rate: Opens, clicks, and replies signal value to recipients
- Authentication: Proper SPF, DKIM, and DMARC configuration
- List acquisition: Trap hits from purchased or scraped addresses
- Volume consistency: Sudden spikes or pauses trigger scrutiny
Monitoring
Sender Score (by Validity), Google Postmaster Tools, and Microsoft SNDS provide ISP-specific reputation data. A declining score across multiple ISPs signals systemic issues that need immediate investigation.
Related Glossary Terms
A/B Testing
A/B testing in email marketing is the practice of sending two variations of an email to a small sample of your list to determine which version performs better before sending the winner to the remaining subscribers.
Abandoned Cart Email
An abandoned cart email is an automated message sent to customers who added items to their online shopping cart but left without completing the purchase. It is one of the highest-converting email types in ecommerce.
AIDA Model for Email
The AIDA model (Attention, Interest, Desire, Action) is a classic copywriting framework used to structure email campaigns that guide subscribers from awareness to conversion.
AMP for Email
AMP for Email is a Google-developed framework that allows email messages to include interactive elements like forms, carousels, accordions, and live content. It turns static emails into dynamic, interactive experiences directly inside the inbox.
Anchoring Effect in Email Marketing
The anchoring effect is a cognitive bias where the first piece of information presented (the anchor) influences subsequent decisions, used in email to frame pricing and value perception.
Announcement Email
An announcement email is a dedicated campaign that communicates a specific update, milestone, or change to subscribers, from product launches and feature releases to company news and events.