How can I effectively avoid spam filters when sending emails?

Summary

Effectively avoiding spam filters involves a multifaceted approach. Technical configurations like SPF, DKIM, and PTR records are crucial for authentication. Content should be relevant, personalized, and avoid spam trigger words and URL shorteners. Maintaining a good sender reputation through engaged subscribers, consistent sending volume, and double opt-in processes is essential. Regular list cleaning and segmentation improve deliverability, while feedback loops and spam checkers help monitor and resolve issues. Ensuring mobile-friendliness and testing emails across different clients further enhance deliverability.

Key findings

  • Technical Authentication: SPF, DKIM, and PTR records are fundamental for authenticating your email sending infrastructure.
  • Content Optimization: Avoid spam trigger words, URL shorteners, and create relevant, personalized content to improve engagement.
  • Sender Reputation Management: Maintain a good sender reputation through consistent sending practices, engaged subscribers, and double opt-in.
  • List Hygiene and Segmentation: Regularly clean your email list, segment subscribers based on engagement, and send targeted content.
  • Monitoring and Testing: Implement feedback loops, use spam checkers, and test emails across different clients to identify and resolve issues.
  • Mobile-Friendliness: Optimizing email for mobile is essential for a positive user experience

Key considerations

  • Prioritize Authentication: Ensure proper SPF, DKIM, and PTR record configuration for email authentication.
  • Refine Content Strategy: Develop a content strategy that focuses on relevance, personalization, and avoids spam triggers.
  • Cultivate Engagement: Focus on building and maintaining a list of engaged subscribers through a double opt-in process and valuable content.
  • Implement Feedback Mechanisms: Set up feedback loops and regularly monitor spam complaints to identify and address issues proactively.
  • Continuous Improvement: Continuously test and optimize your email sending practices based on data and feedback.
  • Testing and Previews: Send previews and use testing tools to ensure message deliverability and rendering are correct.

What email marketers say
11Marketer opinions

To effectively avoid spam filters, several strategies are recommended. These include using spam checkers like Litmus, authenticating emails with SPF, DKIM, and DMARC, and gradually increasing sending volume while maintaining a consistent schedule. Avoiding spam trigger words, regularly cleaning email lists, and testing emails with various clients are also crucial. Additionally, ensuring emails are mobile-friendly, using a double opt-in process, checking for blacklisting, avoiding URL shorteners, and sending email previews are vital for improving deliverability and maintaining a positive sender reputation.

Key opinions

  • Authentication: Implementing SPF, DKIM, and DMARC is critical for verifying sender identity and improving email deliverability.
  • Content: Avoiding spam trigger words and URL shorteners in email content can prevent emails from being flagged as spam.
  • List Hygiene: Regularly cleaning email lists by removing inactive and unsubscribed users helps maintain a high engagement rate and sender reputation.
  • Testing: Testing emails with different email clients and using spam checkers can identify and fix issues before sending to the entire list.
  • Sender Reputation: Gradually increasing sending volume, maintaining consistency, and using double opt-in contribute to building a positive sender reputation.
  • Previews: Sending preview messages can help identify potential problems before a broadcast.

Key considerations

  • Spam Checkers: Utilize tools like Litmus to proactively identify and resolve potential issues.
  • Mobile Friendliness: Ensure emails are mobile-friendly to improve user experience and deliverability.
  • Blacklisting: Monitor your IP address for blacklisting and take prompt action to resolve any issues.
  • Opt-in Process: Implement a double opt-in process to ensure subscribers genuinely want to receive emails.
  • Engagement: Focus on sending relevant and engaging content to maintain high open and click-through rates.
  • Relevance: The content and subject of the email should be relevant to the target audience.
Marketer view

Email marketer from Email on Acid recommends regularly checking if your IP address is on any blacklists and taking steps to get removed if necessary, as being blacklisted can significantly impact your email deliverability.

July 2024 - Email on Acid
Marketer view

Email marketer from HubSpot explains that avoiding the use of spam trigger words (e.g., 'free,' 'guarantee,' 'urgent') in your subject lines and email body can help prevent your emails from being flagged as spam.

August 2022 - HubSpot
Marketer view

Email marketer from ZeroBounce explains that avoiding the use of URL shorteners in your email content can help prevent your emails from being flagged as spam, as spammers often use them to mask malicious links.

April 2023 - ZeroBounce
Marketer view

Email marketer from Email Marketing Forum suggests testing your emails with different email clients and spam filters before sending them to your entire list to identify and fix any potential issues.

January 2024 - Email Marketing Forum
Marketer view

Email marketer from Reddit explains that regularly cleaning your email list by removing inactive subscribers and those who have unsubscribed helps maintain a high engagement rate and improves your sender reputation.

April 2023 - Reddit
Marketer view

Email marketer from Campaign Monitor recommends using a double opt-in process to ensure that subscribers genuinely want to receive your emails, which helps reduce spam complaints and improve your sender reputation.

October 2021 - Campaign Monitor
Marketer view

Email marketer from Mailchimp shares that authenticating your email using SPF, DKIM, and DMARC is crucial for improving deliverability and avoiding spam filters.

September 2024 - Mailchimp
Marketer view

Email marketer from SendGrid explains that gradually increasing your sending volume and maintaining a consistent schedule helps build a positive sender reputation and avoid triggering spam filters.

March 2023 - SendGrid
Marketer view

Email marketer from Omnisend shares that sending email previews to different email addresses and testing different subjects allows you to see how the message looks and what headers or other data is provided by the receiving servers.

August 2024 - Omnisend
Marketer view

Email marketer from Litmus shares that ensuring your emails are mobile-friendly and responsive improves the user experience and can positively impact your deliverability rates.

October 2022 - Litmus
Marketer view

Marketer from Email Geeks shares that Litmus has a spam checker to identify and fix issues causing emails to be blocked by email clients.

September 2023 - Email Geeks

What the experts say
6Expert opinions

To effectively avoid spam filters, strategies include creating stylized links in signature files (though its effectiveness may vary), maintaining a good sender reputation by sending relevant content to engaged subscribers, cleaning email lists by removing invalid and inactive addresses, and implementing feedback loops to monitor and address spam complaints. Sending relevant and personalized content is crucial for improving engagement and reducing spam likelihood.

Key opinions

  • Sender Reputation: Maintaining a good sender reputation is vital; send relevant content to engaged subscribers and monitor your IP address and domain reputation.
  • List Hygiene: Cleaning email lists by removing invalid and inactive addresses is crucial for deliverability.
  • Content Relevance: Sending relevant and personalized content improves engagement and reduces the likelihood of being marked as spam.
  • Feedback Loops: Implementing feedback loops helps monitor spam complaints and address potential issues.
  • Stylized Links: Some delivery consultants recommend stylized links in signatures, but efficacy may vary.

Key considerations

  • Sender Reputation Monitoring: Regularly check your IP address and domain reputation to identify and address any issues proactively.
  • Targeted Content: Tailor your messaging to your audience's interests and needs to improve engagement.
  • Proactive Issue Resolution: Address spam complaints and feedback loop issues promptly to maintain a positive sender reputation.
  • Testing New Techniques: Carefully evaluate the effectiveness of stylized links, as their impact on spam filtering can vary.
  • Inactive Subscribers: Consistently remove addresses of users who don't engage with email content.
Expert view

Expert from Word to the Wise shares that cleaning your email list by removing invalid and inactive email addresses is an important step toward deliverability, therefore avoiding spam filters. Also important is to target active users and avoid sending to those who haven't engaged with your content.

June 2024 - Word to the Wise
Expert view

Expert from Spam Resource explains that maintaining a good sender reputation by sending relevant content to engaged subscribers is vital for avoiding spam filters. They also recommend monitoring your IP address and domain reputation to identify and address any issues.

February 2022 - Spam Resource
Expert view

Expert from Email Geeks shares a method to avoid spam filters: create a highly stylized version of a link in your signature file.

March 2021 - Email Geeks
Expert view

Expert from Email Geeks responds, there are delivery consultants that recommend stylized links in signature files to cold emailers.

June 2022 - Email Geeks
Expert view

Expert from Word to the Wise recommends implementing feedback loops to monitor spam complaints and identify potential issues with your sending practices. Addressing these issues promptly can help improve your sender reputation and avoid spam filters.

March 2025 - Word to the Wise
Expert view

Expert from Word to the Wise explains that sending relevant and personalized content to your subscribers can significantly improve engagement and reduce the likelihood of your emails being marked as spam. It's important to tailor your messaging to your audience's interests and needs.

March 2022 - Word to the Wise

What the documentation says
5Technical articles

To effectively avoid spam filters, several technical aspects are emphasized. Sender reputation, email content, user feedback, and proper authentication via SPF and DKIM records are important factors considered by Gmail's spam filters. Essential practices include using a dedicated IP address, monitoring and reducing bounce rates, promptly removing invalid email addresses, and setting up a reverse DNS (PTR) record to verify identity. Segmenting email lists based on engagement and demographics allows for more targeted and relevant emails, improving deliverability and reducing spam complaints.

Key findings

  • Sender Reputation Factors: Gmail's spam filters consider sender reputation, email content, and user feedback.
  • Authentication: Using SPF and DKIM records helps authenticate emails and verify the sender's identity, improving trust.
  • List Management: Removing invalid email addresses and monitoring bounce rates are crucial for maintaining list health.
  • Infrastructure: Using a dedicated IP address and setting up a reverse DNS (PTR) record verify identity and improve deliverability.
  • Segmentation: Segmenting email lists based on engagement and demographics allows for more relevant emails and reduces spam complaints.

Key considerations

  • Monitor Reputation: Continuously monitor and manage your sender reputation by ensuring positive engagement and addressing negative feedback.
  • Technical Setup: Properly configure SPF, DKIM, and PTR records to authenticate your email sending infrastructure.
  • List Hygiene: Implement a process to regularly clean your email list of invalid and unengaged addresses.
  • Targeted Content: Create targeted content that is relevant to specific segments of your audience to increase engagement.
  • Bounce Rate: Keep bounce rates low by monitoring issues and removing problem addresses.
Technical article

Documentation from Microsoft shares that using a dedicated IP address, monitoring bounce rates, and promptly removing invalid email addresses from your list are essential practices for avoiding spam filters.

February 2024 - Microsoft
Technical article

Documentation from RFC explains that setting up a reverse DNS (PTR) record for your sending IP address can help verify your identity and improve your email deliverability.

July 2024 - RFC
Technical article

Documentation from SparkPost shares that segmenting your email list based on subscriber engagement and demographics allows you to send more targeted and relevant emails, which can improve deliverability and reduce spam complaints.

December 2023 - SparkPost
Technical article

Documentation from AWS explains that using SPF and DKIM records help to authenticate your emails and verify that you are the actual sender, which improves trust with email providers.

January 2022 - AWS
Technical article

Documentation from Google Support explains that Gmail's spam filters consider factors like sender reputation, email content, and user feedback to determine if an email is spam.

January 2025 - Google Support