What happens when a spam trap opens an email, and how do legitimate addresses become spam traps?

Summary

When a pristine spam trap opens an email, it's a strong indication of unethical list acquisition practices, such as scraping or purchasing lists, and it's a major red flag for deliverability. Spamhaus uses these traps to identify and block spammers, potentially leading to blacklisting. Legitimate addresses can become recycled spam traps when mailbox providers convert abandoned or inactive accounts. These addresses, along with 'typo spam traps' created by form validation errors, can damage sender reputation if targeted. To avoid spam traps, it's crucial to practice good list hygiene, including using double opt-in, regularly removing unengaged subscribers, validating email addresses, and monitoring bounce rates. Remember that an email open does not equal consent, emphasizing the importance of explicit permission.

Key findings

  • Pristine Trap = Unethical Acquisition: An email open from a pristine spam trap signals unethical list acquisition practices like scraping or buying lists.
  • Recycled Addresses Become Traps: Legitimate addresses become recycled spam traps when mailbox providers repurpose abandoned or inactive accounts.
  • Typo Traps Exist: Typos in email addresses entered on forms can create 'typo spam traps' when forms lack proper validation.
  • Open ≠ Permission: An email open does not equate to the recipient granting permission to receive emails.
  • Spamhaus Blocks Spammers: Spamhaus uses spam traps to identify and block spammers, which can result in blacklisting and deliverability problems.

Key considerations

  • Prioritize List Hygiene: Maintain strict list hygiene practices, including regular cleaning and validation, to reduce the risk of hitting spam traps.
  • Implement Double Opt-In: Use double opt-in to ensure recipients genuinely consent to receiving emails and to minimize the chance of spam complaints.
  • Monitor Engagement and Bounces: Monitor subscriber engagement and bounce rates to identify and remove inactive or problematic addresses from your list.
  • Validate Email Input: Implement email address validation on forms to prevent typo spam traps from entering your list.
  • Obtain Explicit Consent: Always obtain explicit consent from recipients before sending emails to comply with regulations and maintain a positive sender reputation.

What email marketers say
12Marketer opinions

When a spam trap opens an email, it's a strong signal that the sender's email list is problematic, often indicating unethical list acquisition practices like scraping or purchasing lists. Pristine spam traps identify senders using such methods. Legitimate addresses can become recycled spam traps through abandonment and subsequent repurposing by mailbox providers. Hitting these traps signifies poor list hygiene and can damage sender reputation, leading to deliverability issues and blacklisting. To avoid spam traps, marketers should prioritize list hygiene by using double opt-in, regularly removing unengaged subscribers, validating email addresses, and monitoring bounce rates and unsubscribes.

Key opinions

  • Spam Trap Opens = Bad List: An email open from a spam trap indicates the sender likely acquired email addresses unethically.
  • Pristine vs Recycled: Pristine spam traps are new addresses, while recycled spam traps are previously legitimate addresses repurposed after a period of inactivity.
  • COI/DOI Still Susceptible: Even addresses obtained through Confirmed Opt-In (COI) or Double Opt-In (DOI) can become recycled spam traps.
  • Damaged Reputation: Hitting spam traps negatively impacts sender reputation, potentially leading to blacklisting and deliverability problems.

Key considerations

  • List Hygiene: Implement rigorous list hygiene practices, including regular cleaning and validation, to minimize the risk of hitting spam traps.
  • Double Opt-In: Use double opt-in to ensure recipients genuinely consent to receive emails.
  • Engagement Monitoring: Monitor engagement metrics and remove unengaged subscribers to prevent legitimate addresses from becoming recycled spam traps.
  • Proactive Management: Take a proactive approach to email list management to maintain a healthy sender reputation and ensure optimal deliverability.
Marketer view

Email marketer from Constant Contact shares that if a spam trap opens an email, it's a strong indicator of poor list quality and can severely damage your sender reputation and deliverability. This is due to spam traps indicating the address has come from a purchased/harvested email list.

October 2023 - Constant Contact
Marketer view

Email marketer from HubSpot explains that hitting a spam trap can negatively impact your sender reputation, leading to lower deliverability rates and potentially getting blacklisted. This emphasizes the importance of proactive list management.

July 2021 - HubSpot
Marketer view

Email marketer from SendGrid explains that to avoid spam traps, senders should practice good list hygiene, use confirmed opt-in, and regularly remove unengaged subscribers. Engaging new users regularly will also help you avoid spam traps.

June 2024 - SendGrid
Marketer view

Email marketer from Mailjet shares that a lack of engagement can cause legitimate addresses to turn into recycled spam traps. Regularly removing unengaged subscribers helps to maintain list hygiene and avoid these traps.

February 2022 - Mailjet
Marketer view

Email marketer from Email Marketing Forum recommends using a double opt-in process and regularly cleaning your list as crucial steps to avoid spam traps. They also advise monitoring bounce rates and unsubscribes to identify potential problems early.

August 2023 - Email Marketing Forum
Marketer view

Email marketer from Reddit r/emailmarketing suggests that one of the best ways to avoid spam traps is to use double opt-in and regularly clean your email list. Remove inactive subscribers and ensure your list is permission-based.

October 2022 - Reddit r/emailmarketing
Marketer view

Email marketer from Neil Patel's Blog explains that when a pristine spam trap opens an email, it's a major red flag. These traps are specifically created to catch spammers, so an open indicates that the sender's list likely contains addresses obtained through unethical means. He also notes that recycled spam traps, which were once legitimate email addresses, start sending emails to opt-in lists, if the sender continues to send emails to these addresses then this is a red flag to mailbox providers.

May 2023 - Neil Patel's Blog
Marketer view

Marketer from Email Geeks shares that even addresses properly collected through Confirmed Opt-In (COI) or Double Opt-In (DOI) can become recycled spam traps. If there's been a long period of inactivity or improper bounce processing, spam traps can still exist in the list.

April 2023 - Email Geeks
Marketer view

Marketer from Email Geeks explains that if a spam trap opens an email, it means the operator is likely reviewing the email, which is usually a negative indicator unless collaborating to resolve a false positive. It's generally safe to consider a never-opened email as a potential spam trap.

September 2023 - Email Geeks
Marketer view

Email marketer from ActiveCampaign emphasizes that sending emails only to those who have explicitly given permission is key to avoiding spam traps. Using double opt-in is a recommended practice to ensure consent.

January 2024 - ActiveCampaign
Marketer view

Email marketer from EmailOversight Blog shares that spam traps are designed to identify senders who aren't following best practices. When a pristine spam trap opens an email, it indicates the sender is likely using scraped or purchased lists. Recycled spam traps occur when legitimate addresses are abandoned and later turned into traps; hitting these suggests poor list hygiene.

June 2024 - EmailOversight Blog
Marketer view

Email marketer from Litmus explains the importance of list hygiene in avoiding spam traps. Regularly cleaning lists by removing unengaged subscribers and validating email addresses can prevent deliverability issues caused by hitting spam traps.

February 2024 - Litmus

What the experts say
4Expert opinions

Spam traps are identified as pristine or recycled addresses. Pristine spam traps are fake email addresses never used by real users and used to catch spammers. Recycled spam traps are legitimate addresses that have been abandoned and repurposed. Email opens from spam traps, especially pristine ones, are a major red flag. Even with proper opt-in, poor list hygiene can lead to legitimate addresses becoming spam traps, due to a lack of maintenance and validation. It's important to note that an email open does not automatically mean there was explicit permission granted by the recipient.

Key opinions

  • Pristine vs. Recycled Spam Traps: Pristine spam traps are fake addresses, while recycled spam traps are repurposed legitimate addresses.
  • Open ≠ Permission: An email open does not equate to the recipient giving explicit permission to be emailed.
  • List Hygiene Matters: Even with opt-in, poor list maintenance can result in legitimate addresses becoming spam traps.
  • Several Reasons for Hitting Traps: Several reasons can contribute to hitting spam traps, including list scraping, purchasing lists, or poor list hygiene.

Key considerations

  • Validate Email Addresses: Routinely validate email addresses on your list to avoid sending to spam traps.
  • Maintain List Hygiene: Implement proper list hygiene practices, including regular cleaning and validation.
  • Obtain Explicit Permission: Ensure you have explicit permission from recipients before sending emails.
  • Understand Spam Trap Types: Be aware of the different types of spam traps and how they operate.
Expert view

Expert from Word to the Wise explains that hitting spam traps can be due to various reasons, including list scraping, purchasing lists, or poor list hygiene. She emphasizes that even legitimate addresses can become traps if they are not properly maintained and validated.

August 2024 - Word to the Wise
Expert view

Expert from Spamresource answers questions about the different types of spam traps that are generally categorised by Pristine and Recycled. Pristine spam traps are addresses that have never been used by real users so are automatically considered bad. Recycled addresses have been used previously however have now been converted to spam traps.

June 2021 - Spamresource
Expert view

Expert from Email Geeks explains that an email open does not equal permission. Opens are used for many things, and opening an email does not mean the recipient requested it.

March 2025 - Email Geeks
Expert view

Expert from Email Geeks shares that some of the first spam traps were fake addresses put in forms, due to the high volume of spam.

April 2022 - Email Geeks

What the documentation says
4Technical articles

Spam traps are used by organizations like Spamhaus to identify and block spammers, leading to blacklisting and deliverability issues. Email addresses become recycled spam traps when mailbox providers convert abandoned or inactive addresses. There are also 'typo spam traps' caused by lack of validation on email input forms. Sending to these recycled addresses, or those with typos, indicates poor list hygiene and damages sender reputation.

Key findings

  • Spamhaus Use: Spamhaus uses spam traps to identify and block spammers, resulting in blacklisting.
  • Recycled Addresses: Mailbox providers convert abandoned/inactive addresses into recycled spam traps.
  • Typo Traps: Lack of validation on email input forms leads to typo spam traps.
  • Poor Hygiene = Damage: Sending to recycled addresses or those with typos indicates poor list hygiene and damages sender reputation.

Key considerations

  • Clean Email Lists: Maintain clean email lists to avoid Spamhaus traps.
  • Address Validation: Validate email addresses on input forms to avoid typo spam traps.
  • Engagement Monitoring: Monitor subscriber engagement and remove inactive addresses.
  • Reputation Management: Implement strong list hygiene practices to protect sender reputation.
Technical article

Documentation from Spamhaus explains that Spamhaus uses spam traps to identify and block spammers. Hitting a Spamhaus spam trap results in listing on their blocklists, impacting email deliverability. They outline various types of spam traps, including pristine and recycled traps, and emphasize the importance of clean email lists to avoid them.

November 2024 - Spamhaus
Technical article

Documentation from Return Path (now Validity) explained that ISPs recycle email addresses that have been inactive for an extended period. These addresses are converted into spam traps. Sending to these recycled addresses indicates poor list hygiene and can damage sender reputation.

December 2022 - Return Path
Technical article

Documentation from MailerQ explains that there are different types of spam traps. The most common of these being 'typo spam traps' where forms that require an email address do not validate the email address properly and therefore the email address submitted is technically incorrect. A recycled email address could also be used as a spam trap.

September 2024 - MailerQ
Technical article

Documentation from Validity explains that email addresses become recycled spam traps when mailbox providers convert abandoned or inactive addresses into spam traps. Senders who continue to email these addresses, even after they've been inactive for a long time, risk being identified as spammers.

June 2022 - Validity