A SpamAssassin score is a numerical value assigned to an email after analysis by Apache SpamAssassin, an open-source spam filtering framework. The score indicates how likely an email is to be classified as spam based on multiple checks and rules.
What Is a SpamAssassin Score?
SpamAssassin evaluates emails using a wide range of tests, such as header analysis, content filters, Domain Name System (DNS) checks, and Bayesian filtering. Each rule contributes positive or negative points to the overall score. The higher the score, the more likely the email is considered spam.
For example:
- A score of 0–2 usually indicates a safe, non-spam email.
- A score above 5 (default threshold) may classify the email as spam.
SpamAssassin is widely used by internet service providers (ISPs), hosting providers, and corporate mail systems to filter unsolicited messages before they reach the inbox.
How Does SpamAssassin Scoring Work?
The scoring process follows these steps:
- Rule application: SpamAssassin runs a series of tests on email headers, body content, and metadata.
- Point assignment: Each test adds or subtracts points. For example:
- Missing or invalid SPF (Sender Policy Framework) may add points.
- The presence of certain keywords or suspicious formatting adds points.
- Proper DKIM (DomainKeys Identified Mail) and DMARC (Domain-based Message Authentication, Reporting, and Conformance) alignment may subtract points.
- Final score calculation: All rule scores are summed up to create the final SpamAssassin score.
- Action decision: Based on configured thresholds, the email is delivered, flagged, or quarantined as spam.
Why Is SpamAssassin Score Important?
SpamAssassin scores matter because they:
- Affect deliverability: High scores increase the risk of emails being flagged as spam.
- Guide email optimization: Help marketers and businesses identify issues in headers, content, or authentication.
- Enhance security: Detects phishing and malicious content before reaching end-users.
- Improve compliance: Supports ISPs and businesses in enforcing anti-spam regulations.
Without monitoring SpamAssassin scores, even legitimate emails can end up in spam folders.
Common Use Cases
SpamAssassin scoring is used for:
- Email filtering: Blocking or quarantining high-risk emails at the server level.
- Campaign testing: Evaluating promotional emails before sending to improve inbox placement.
- Compliance checks: Making sure emails adhere to best practices and authentication standards.
- Fraud prevention: Identifying phishing or spoofed emails.
Example scenario: A marketer tests an email campaign through SpamAssassin and finds a score of 6.2 due to missing DKIM and excessive promotional terms. After fixing these issues, the score drops to 1.5, improving deliverability.
FAQs About SpamAssassin Score
What is the default SpamAssassin threshold for spam?
The default is 5.0, but administrators can adjust it based on their filtering needs.
Can I reduce my SpamAssassin score?
Yes, by authenticating your domain (SPF, DKIM, DMARC), improving email content, and maintaining good list hygiene.
Does SpamAssassin guarantee emails won’t go to spam?
No, it is one of many factors ISPs use. Deliverability also depends on engagement and sender reputation.
