Deliverability & Infrastructure

Spam Trap

A spam trap is an email address used by ISPs and anti-spam organisations to identify senders with poor list practices.

What Is Spam Trap?

There are several types of spam traps. Pristine traps are email addresses that have never been used by a real person — they're created solely to catch spammers who scrape or purchase email lists. Recycled traps are old, abandoned email addresses that ISPs have repurposed. After an account is inactive for a long period, the ISP may reactivate it as a trap. Typo traps exploit common misspellings of popular email domains (e.g., gmial.com instead of gmail.com). Hitting any type of spam trap is a serious red flag that can instantly damage your sender reputation.

Why It Matters for Newsletters

Sending to even a single spam trap can result in your IP or domain being blacklisted. ISPs view spam trap hits as evidence of poor list acquisition practices — either you're buying lists, scraping addresses, or not maintaining your list. The consequences are severe and immediate: mass filtering of your emails to spam across all ISPs that share blacklist data.

Best Practices

  1. Never buy or rent email lists
  2. Use double opt-in to verify all subscriber addresses
  3. Regularly clean your list of inactive subscribers
  4. Validate email addresses at the point of collection
  5. Monitor for sudden drops in engagement that might indicate spam trap hits

How Aldus Handles This

Aldus's double opt-in process and automatic list hygiene help prevent spam trap hits. The platform removes bounced addresses and flags suspicious signups, keeping your list clean and your reputation protected.

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