What is a “shadow ban” and how does it appear?

A shadow ban (or silent filtering) occurs when messages are accepted but consistently routed to spam without explicit rejection.

How shadow bans work:

• Messages are accepted during SMTP transaction (no bounce)
• Delivery appears successful in your sending tools
• Messages route directly to spam folder
• Recipients never see the message in their inbox
• No explicit error or notification to sender

Detection signals:

• Open and reply rates drop dramatically
• Seed tests show consistent spam placement
• Recipients report finding messages in spam
• Metrics diverge from historical patterns
• No bounces despite apparent non-delivery

Why shadow bans happen:

• Accumulated reputation damage
• Pattern matching to spam behaviors
• Low engagement history for your domain
• Content or link patterns matching spam

Response:

• Confirm with seed testing across providers
• Reduce volume significantly
• Focus on highest-engagement recipients only
• Investigate and address reputation issues
• May need extended recovery period

Shadow bans are particularly dangerous because they're invisible without active testing. The ship appears to sail smoothly while cargo never reaches port.