Summary
AOL and Yahoo flag emails as spam due to a combination of factors related to sender reputation, user engagement, email authentication, content, and list hygiene. A negative sender reputation, often stemming from user behavior indicating emails are unwanted, being blacklisted, or sending to spam traps, is a primary driver. Lack of user engagement and sending unsolicited emails also contribute significantly. Failing to properly authenticate emails with SPF, DKIM, and DMARC makes it difficult for ISPs to verify legitimacy, increasing the likelihood of spam flagging. Suspicious content, poor formatting, spam trigger words, and misleading subject lines can also trigger spam filters. Maintaining a clean email list and gradually increasing email volume with new IPs are essential for improving deliverability. Ultimately, sending relevant, personalized emails to engaged subscribers while adhering to email best practices is crucial to avoid spam flagging by AOL and Yahoo.
Key findings
- Sender Reputation is Paramount: A strong, positive sender reputation is the most critical factor. This is influenced by IP reputation, domain reputation, spam complaints, and blocklist status.
- User Engagement Matters: User interaction (opens, clicks, deletions, spam reports) signals to ISPs whether users want the emails. Low engagement rates significantly increase spam flagging.
- Email Authentication is Essential: Proper implementation and maintenance of SPF, DKIM, and DMARC records are crucial for verifying sender identity and preventing domain spoofing. Authentication helps ISPs trust emails.
- Content Quality Influences Deliverability: Spam trigger words, poor formatting, excessive use of images without alt text, and misleading subject lines can trigger spam filters, regardless of sender reputation.
- List Hygiene is Non-Negotiable: Regularly cleaning email lists to remove inactive or invalid addresses reduces bounce rates, improves sender reputation, and minimizes the risk of being flagged as spam.
Key considerations
- Actively Manage Your Reputation: Use tools like Google Postmaster Tools and Sender Score to monitor sender reputation. Proactively address any issues and work to improve your reputation score.
- Segment and Personalize Your Emails: Tailor email content to specific segments of your audience to increase engagement. Personalize emails to make them more relevant and desirable to recipients.
- Prioritize Email Authentication: Ensure that SPF, DKIM, and DMARC records are correctly configured and regularly updated. Implement a DMARC policy to instruct receiving servers on how to handle authentication failures.
- Optimize Email Content and Design: Avoid spam trigger words, use clear and concise subject lines, ensure emails are well-formatted with a healthy text-to-image ratio, and use alt text for images.
- Practice Rigorous List Hygiene: Implement a process for regularly cleaning your email list, removing inactive subscribers, and validating email addresses to maintain a healthy list.
- Get Explicit Permission: Always get explicit permission before sending someone emails and honor unsubscribe requests promptly.
- Monitor Sending Volume: Gradually increase sending volume, especially when using a new IP address or domain, to establish a positive sender reputation.
What email marketers say
12 marketer opinions
Emails are flagged as spam by AOL and Yahoo for a variety of reasons, including poor sender reputation, sending to unengaged subscribers, using spam trigger words, high spam complaint rates, lacking proper authentication (SPF, DKIM, DMARC), suspicious content, poor email formatting, misleading subject lines, and a lack of unsubscribe options. User engagement is also a significant factor, as ISPs monitor how users interact with emails. Maintaining a clean email list, gradually increasing email volume with new IPs, personalizing emails, and sending relevant content are crucial for improving deliverability and avoiding spam filters. Reputation data influences spam filtering, and being added to a blacklist can hinder email delivery. Emails that are well-coded, have a healthy text-to-image ratio, and use alt text for images are also less likely to be flagged as spam.
Key opinions
- Sender Reputation: Poor sender reputation is a primary driver for spam flagging. This encompasses factors like domain reputation, IP address reputation, and historical spam complaints.
- User Engagement: ISPs analyze user engagement with emails (opens, clicks, etc.) to determine if emails are wanted. Low engagement leads to increased spam flagging.
- Authentication: Lack of proper email authentication (SPF, DKIM, DMARC) makes it difficult for ISPs to verify the legitimacy of emails, leading to higher spam filtering rates.
- Content & Formatting: Spam trigger words, excessive use of exclamation points or ALL CAPS, poor HTML coding, and high image-to-text ratios contribute to spam flagging.
- List Hygiene: Maintaining a clean email list by removing inactive or invalid addresses reduces bounce rates and improves sender reputation.
Key considerations
- Monitor Reputation: Actively monitor your sender reputation using tools like Google Postmaster Tools and take steps to improve it if needed.
- Improve Engagement: Focus on sending relevant, personalized emails to encourage user engagement. Segment your list to send targeted content.
- Implement Authentication: Set up SPF, DKIM, and DMARC records to authenticate your emails and prevent spoofing.
- Review Content: Avoid using spam trigger words, excessive punctuation, and ensure emails are well-formatted with a healthy text-to-image ratio.
- Clean Email List: Regularly clean your email list by removing inactive or invalid addresses to improve deliverability and sender reputation.
- IP Warmup: Gradually increase sending volume on a new IP address to establish a positive reputation with ISPs.
- Permission: Always get permission to send subscribers emails. Send relevant content to people who want to receive it.
Marketer view
Marketer from Email Geeks reports that Yahoo and AOL came back for them naturally.
18 Oct 2022 - Email Geeks
Marketer view
Email marketer from Quora shares that maintaining a clean email list by removing inactive or invalid email addresses reduces bounce rates and helps improve sender reputation, thereby decreasing the chances of being marked as spam.
20 Feb 2024 - Quora
What the experts say
4 expert opinions
AOL and Yahoo flag emails as spam primarily due to negative reputation factors, which can stem from user behavior indicating the emails are unwanted, such as not engaging with the content. Other reasons include being blacklisted by ESPs or companies, sending spam-like content, failing to authenticate emails properly, and sending to spam traps. The consensus is that user engagement and sender reputation are critical determinants in whether emails are marked as spam.
Key opinions
- User Reaction: User behavior and engagement (or lack thereof) significantly influence whether ISPs flag emails as spam. Unwanted emails, as perceived by users, contribute to deliverability issues.
- Reputation: Negative reputation factors, based on data collected by ISPs, lead to filtering and blocking of emails. This reputation is a key driver behind AOL and Yahoo's spam flagging.
- Blacklisting: Being added to a blacklist by ESPs or other organizations results in blocked emails, as these lists are used to filter out potentially harmful or unwanted senders.
- Content & Authentication: Spam-like content and failure to authenticate emails (SPF, DKIM, DMARC) increase the likelihood of emails being flagged as spam by AOL and Yahoo.
Key considerations
- Improve Engagement: Focus on sending emails that users want to receive and engage with. This involves creating relevant content, segmenting audiences, and avoiding tactics that might be perceived as spammy.
- Monitor Reputation: Regularly check sender reputation using tools like Google Postmaster Tools and take steps to address any negative feedback or issues.
- Avoid Blacklists: Ensure email practices align with best practices to avoid being added to blacklists. Monitor blacklists and take corrective actions if listed.
- Implement Authentication: Ensure that SPF, DKIM, and DMARC records are correctly configured to authenticate emails and prevent spoofing.
- Review Content: Carefully review email content to avoid using spam trigger words, misleading subject lines, and other tactics that could trigger spam filters.
Expert view
Expert from Spamresource shares that emails get blocked because ESPs or companies added you to a blacklist, your messages contain spam-like content, you aren't authenticating your emails, or you send spam traps emails.
24 Feb 2022 - Spamresource
Expert view
Expert from Spamresource explains that reputation data is used to filter and sometimes block mail. If Yahoo and AOL are flagging mail, this is based on some negative reputation factor.
14 Jul 2022 - Spamresource
What the documentation says
5 technical articles
AOL and Yahoo flag emails as spam due to several technical and policy-related reasons, as detailed in official documentation. These include sending unsolicited emails, containing suspicious content, lacking proper email authentication (SPF, DKIM, DMARC), having a poor sender reputation, and being listed on a major blocklist due to spam activities. Implementing a DMARC policy to handle authentication failures, providing clear unsubscribe options, and actively managing sender reputation are crucial to avoid spam flagging.
Key findings
- Authentication: Proper SPF, DKIM, and DMARC records are essential for ISPs to verify the legitimacy of emails and reduce the risk of spam flagging. DMARC policies instruct receiving servers on how to handle authentication failures, preventing domain spoofing.
- Sender Reputation: A poor sender reputation, often stemming from spam complaints or being listed on blocklists, leads to filtering or blocking of emails by ISPs like AOL and Yahoo.
- Unsolicited Content: Sending unsolicited emails, which are often associated with spam, contributes to higher spam flagging rates.
- Bulk Sending Policies: Bulk senders are responsible for ensuring they have clear unsubscribe options and managing their sender reputation to avoid being flagged as spam.
- Blocklisting: Inclusion on a major blocklist, like those maintained by Spamhaus, directly results in ISPs filtering or blocking emails.
Key considerations
- Implement Authentication: Configure SPF, DKIM, and DMARC records correctly to authenticate emails and prevent domain spoofing. Regularly review and update these records.
- Manage Reputation: Monitor sender reputation using tools like Google Postmaster Tools and take proactive steps to address any negative feedback or issues. Reduce spam complaints by ensuring relevant and desired content.
- Unsubscribe Options: Provide clear and easily accessible unsubscribe options in all bulk emails to comply with regulations and reduce spam complaints.
- Avoid Blocklists: Adhere to email best practices to avoid being added to blocklists. If listed, promptly take corrective actions and request delisting.
- Content Review: Review email content for suspicious elements or spam triggers that could increase the likelihood of emails being flagged as spam.
Technical article
Documentation from Spamhaus shares that being listed on a major blocklist due to spam activity can cause ISPs to filter or block emails from your domain or IP address.
26 Mar 2024 - Spamhaus
Technical article
Documentation from DMARC.org explains that implementing a DMARC policy tells receiving mail servers what to do with emails that fail SPF and DKIM checks, helping to prevent domain spoofing and phishing attacks.
2 Jul 2022 - DMARC.org
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