Agencies send on behalf of many client domains and must isolate reputation per client.
What spam filter content triggers are#
Content filtering evaluates message text, HTML, links, and attachments for spam patterns: deceptive phrasing, URL shorteners, image-only bodies, mismatched link text, and known malicious domains.
Why it matters#
Reputation dominates, but content still tips borderline decisions and drives the complaints that build reputation in the first place.
Implementation plan for marketing agencies#
- Keep a healthy text-to-image ratio and always include a plain-text part.
- Link to your own domain; avoid shorteners and tracking domains with poor reputation.
- Make link text match the destination.
- Test rendering and spam scores before sending.
Priorities specific to marketing agencies#
Agencies send on behalf of many client domains and must isolate reputation per client. Weight your effort toward the steps above that address this constraint first, and measure with metrics that match how marketing agencies generate value from email.
Common mistakes#
- Image-only emails.
- Tracking links on a shared domain used by spammers.
Frequently asked questions#
Are spam trigger words still a thing?
Much less than a decade ago. Modern filters are statistical and reputation-weighted. Deceptive intent matters more than any single word.