It was a surprising moment when I saw a recent email from Really Good Emails land directly in my spam folder. The automated message from my email provider explained, "It is similar to messages that were identified as spam in the past." This immediately raised a flag because Really Good Emails is known for its high-quality content and commitment to best practices.
The experience highlights a crucial point: even the most reputable senders can occasionally face deliverability issues. It's a complex dance between sender reputation, content quality, recipient engagement, and the ever-evolving algorithms of internet service providers (ISPs). My own inbox showed it in spam, while others reported it went straight to their main inbox. This variation underscores that inbox placement isn't a one-size-fits-all scenario. Let's delve into the common reasons why even 'really good emails' might occasionally miss the inbox and how to prevent it.
Sender reputation and infrastructure
One of the primary factors determining if an email reaches the inbox or the spam folder is the sender's reputation. This includes the reputation of your sending domain and the IP address. If either has a history of sending unwanted or problematic emails, even legitimate messages can be flagged. ISPs constantly monitor sending patterns, spam complaints, and engagement metrics to build a profile of your sending trustworthiness. A sudden spike in volume or a change in content can sometimes trigger a review, even for established senders.
Proper email authentication is another non-negotiable aspect of good deliverability. This includes SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance). These protocols help receiving servers verify that an email truly originates from the claimed sender and hasn't been tampered with. Missing or misconfigured authentication records are a common reason for legitimate emails to be routed to spam or even rejected outright. Regularly checking your DMARC monitoring and records is essential. For more about authentication, read our simple guide to DMARC, SPF, and DKIM.
Furthermore, being listed on an email blocklist (or blacklist) can significantly hinder your deliverability. These lists compile IP addresses or domains known for sending spam or engaging in malicious activities. If your sending infrastructure ends up on a major blacklist, your emails will likely be blocked or sent to spam by a wide range of providers. Even if your email is otherwise "good," a blocklist entry can override other positive signals. You can learn more about this in our guide on what happens when your domain is on an email blacklist. It's important to monitor these lists regularly and take swift action if you find yourself on one.
Recipient engagement plays a significant role in how ISPs perceive your emails. If your subscribers consistently open, click, and interact positively with your messages, it signals to providers like Gmail and Yahoo that your content is valued. Conversely, low engagement rates, where emails are rarely opened or clicked, can harm your sender reputation and lead to messages being routed to spam. ISPs track these metrics closely to determine inbox placement. Learn how to improve your domain reputation using Google Postmaster Tools.
Spam complaints are perhaps the most damaging signal. Even a small number of users marking your email as spam can have a disproportionately negative impact on your sender score. This tells ISPs that your emails are unwanted, regardless of how good you think they are. To avoid this, always ensure clear consent, manage expectations, and provide an easy unsubscribe option. Negative engagements, such as frequent spam reports, should be minimized.
Furthermore, if recipients simply delete your emails without opening them, or move them to trash, these are also negative signals. ISPs interpret such actions as disinterest, which can gradually degrade your sender reputation. It's crucial to understand why your email deliverability rate is wrong and what hidden factors might be affecting it.
The impact of low engagement
Even for a well-known brand, a period of low engagement from a segment of their list can lead to deliverability issues for that segment. If a recipient rarely opens your emails, ISPs might start filtering future messages to spam, assuming disinterest. This is why list hygiene and re-engagement campaigns are so important to avoid your emails being marked as spam.
Content quality and formatting
The content and formatting of your emails also play a significant role in spam filtering. Certain elements can trigger spam filters, regardless of your sender reputation. This includes the overuse of spam trigger words (e.g., "free," "money-back guarantee," "win"), excessive exclamation points, or all caps. While these might seem like minor details, collectively they can paint a picture of a suspicious email.
Beyond words, the structure of your email matters. Image-heavy emails with very little text, or emails with broken HTML, can sometimes raise red flags. Spam filters often look for a healthy text-to-image ratio and clean, well-coded HTML. Including large attachments or using excessive links can also be perceived as suspicious. It's about striking a balance that looks legitimate and professional, rather than trying to bypass filters with tricks. Google recommends checking your email content for these issues.
Even if your content is genuinely good, inconsistencies can cause issues. For example, if your sending domain doesn't align with the domain in your links, or if the email client cannot render the email properly, it can trigger spam filters. This is why A/B testing your emails and carefully reviewing them across different clients before sending is crucial.
Potential content issues
Spammy keywords: Using words commonly associated with scams (e.g., "Click here," "Act now").
Image-heavy designs: Emails with too many images and not enough text, making them look like spam.
Broken formatting: Poorly coded HTML or responsive design issues.
Best practices for content
Clear subject lines: Be concise and honest about your email's content.
Balanced content: Aim for a healthy text-to-image ratio and use alt text for images.
Valid HTML: Ensure your email's HTML is clean and properly formatted.
List hygiene and sending practices
Maintaining a clean and engaged email list is paramount for deliverability. Sending emails to invalid, inactive, or unengaged addresses can significantly hurt your sender reputation and increase your chances of landing on a blocklist. Many factors trigger spam filters, and a dirty list is a prime offender. One particular threat is spam traps. These are email addresses specifically designed to catch senders with poor list hygiene.
If you hit a spam trap, it's a strong signal to ISPs that you might be acquiring addresses improperly or neglecting your list, leading to severe reputation damage and potential blacklisting. Regularly cleaning your list, removing inactive subscribers, and implementing a double opt-in process are essential steps to avoid spam traps and improve your inbox placement. This ensures that you're only sending to genuinely interested recipients, which fosters positive engagement.
Sending frequency also matters. Bombarding your subscribers with too many emails can lead to fatigue, low engagement, and increased spam complaints. Find the right balance that keeps your audience engaged without overwhelming them. A high volume of emails without corresponding high engagement can signal to ISPs that your emails are unwanted, leading them to the junk folder. This is especially true for email newsletters or marketing emails.
Practice
Impact on deliverability
Double opt-in: Requires subscribers to confirm their interest.
Significantly reduces spam complaints and improves engagement.
Regular list cleaning: Removing inactive or bounced emails.
Avoids spam traps and maintains a healthy sender reputation.
Segmentation: Sending targeted content to relevant audience segments.
Increases relevance and engagement, reducing spam flags.
Views from the trenches
Best practices
Maintain strong sender authentication: SPF, DKIM, and DMARC are non-negotiable for deliverability.
Regularly monitor your domain and IP reputation using tools like Google Postmaster Tools.
Segment your audience and personalize content to increase engagement and relevance.
Implement double opt-in for new subscribers to ensure explicit consent and reduce spam complaints.
Consistently clean your email list by removing inactive subscribers and managing bounces to avoid spam traps.
Common pitfalls
Neglecting email authentication, leading to messages failing verification checks.
Ignoring low engagement rates or high spam complaint rates, which degrade sender reputation.
Sending to outdated or unverified email lists, increasing bounce rates and spam trap hits.
Using excessive images, spammy keywords, or broken HTML that triggers spam filters.
Sending emails too frequently, leading to subscriber fatigue and increased unsubscribes.
Expert tips
Focus on building relationships with your subscribers to foster long-term engagement.
Continuously test your email content across different email clients to catch rendering issues.
Understand that inbox placement is dynamic and requires ongoing monitoring and adaptation.
Collaborate with your IT or development team to ensure proper DNS configuration for email records.
Prioritize email deliverability as a core component of your overall marketing strategy.
Marketer view
Marketer from Email Geeks says they had no issue with Really Good Emails and it went straight to their main inbox across all their subscribed emails.
2024-09-25 - Email Geeks
Marketer view
Marketer from Email Geeks says it went to their spam folder for one account, but the main inbox for others.
2024-09-25 - Email Geeks
Addressing deliverability challenges
The case of Really Good Emails occasionally landing in spam reminds us that email deliverability is a multi-faceted challenge, not a static achievement. It's a continuous process of managing sender reputation, adhering to technical standards, optimizing content, and nurturing recipient engagement. There's no single reason why an email might go to spam, but rather a combination of factors that ISPs evaluate.
By understanding and proactively addressing these elements – from strong authentication and active list management to thoughtful content creation – you can significantly improve your chances of consistently reaching the inbox. Continuous email deliverability testing and monitoring your metrics are key to staying ahead in the ever-evolving world of email deliverability.
Gmail and 
Yahoo that your content is valued. Conversely, low engagement rates, where emails are rarely opened or clicked, can harm your sender reputation and lead to messages being routed to spam. ISPs track these metrics closely to determine inbox placement. Learn how to improve your domain reputation using Google Postmaster Tools.
