Spam triggers
📖 3 min readUpdated 2026-04-19
Spam filters look for patterns in content, structure, and sending behavior. Avoiding triggers improves inbox placement.
Content triggers
- ALL CAPS
- Excessive exclamation!!!
- Words: FREE, ACT NOW, GUARANTEED
- Too many links
- Large images with little text
Structure triggers
- Image-only email
- Shortened URLs
- Weird formatting
- Missing plain-text version
Sending triggers
- Volume spikes
- Sending too fast to unengaged
- Purchased lists
Test before sending
Send to Mail-tester.com, get score. Aim for 9+/10.