Summary
Lower open rates and spam placement in Gmail result from a complex interplay of factors, including sender reputation, email authentication, content, design, recipient engagement, list hygiene, and Gmail's intricate spam filtering algorithms. Improving these areas is vital to ensuring emails reach the inbox.
Key findings
- Gmail's Spam Filters: Gmail employs algorithms and numerous signals like user reports, sender reputation, and content analysis to determine email placement.
- Sender Reputation: Sender reputation, encompassing IP address and domain reputation, significantly influences deliverability. A negative reputation increases spam filtering.
- Email Authentication: Proper email authentication (SPF, DKIM, DMARC) is crucial to verify sender legitimacy and prevent spoofing.
- Content Issues: Email content, including subject lines, spam trigger words, excessive links, and poor formatting, can trigger spam filters.
- Recipient Engagement: Gmail heavily weighs recipient engagement (opens, clicks, replies). Low engagement increases the likelihood of spam filtering.
- List Hygiene: Poor list hygiene, sending to old or unengaged addresses, negatively impacts sender reputation and deliverability.
- Email Design: Poorly designed emails, broken HTML, large images, and accessibility issues are more likely to be flagged as spam.
- IP Blacklists: An IP address on a blacklist can cause emails to be blocked or sent to spam.
- New Domains: New domains require a warm-up period to establish a sending reputation.
- Complaint Rates: High complaint rates contribute to emails being sent to spam.
- Personalisation and Segmentation: Personalized content to the right audiences can improve delivery to the inbox.
Key considerations
- Monitor Sender Reputation: Regularly monitor your sender reputation to identify and address any issues.
- Implement Email Authentication: Implement SPF, DKIM, and DMARC to authenticate emails and prevent spoofing.
- Optimize Email Content: Avoid spam trigger words, use clear and concise language, and ensure content is relevant and valuable.
- Improve Recipient Engagement: Encourage recipients to engage with your emails through valuable and targeted content.
- Maintain a Clean Email List: Regularly remove inactive and invalid email addresses from your list.
- Optimize Email Design: Ensure emails are properly coded, responsive, and accessible.
- Check IP Address: Check and ensure your IP address is not on any blacklists.
- Warm-Up New Domains: Gradually increase sending volume when using a new domain to establish a sending reputation.
- Monitor and Reduce Complaints: Actively monitor and minimize spam complaint rates by honoring opt-out requests and sending relevant content.
What email marketers say
10 marketer opinions
Emails land in spam and experience lower open rates in Gmail due to a combination of factors influencing spam filters and sender reputation. These factors range from sender reputation, email authentication, content, design, recipient engagement, and list hygiene. Improving these areas is crucial to reaching the inbox.
Key opinions
- Spam Filters: Gmail uses algorithms (spam filters) to determine whether an email lands in the inbox or spam folder based on multiple factors.
- Sender Reputation: Sender reputation, encompassing IP address and domain reputation, significantly impacts email placement. A poor reputation leads to increased spam filtering.
- Email Authentication: Proper email authentication (SPF, DKIM, DMARC) is essential to prove sender legitimacy and avoid being flagged as spam.
- Content Issues: Email content, including subject lines and body content, can trigger spam filters if it contains spam trigger words, misleading information, or poor formatting.
- Recipient Engagement: Recipient engagement (opens, clicks, replies) is a key signal for Gmail. Low engagement rates can lead to increased spam filtering.
- List Hygiene: Poor list hygiene (sending to old, unengaged addresses) negatively impacts sender reputation and deliverability.
- Design and Formatting: Poorly designed emails with broken HTML, large images, or accessibility issues are more likely to be flagged as spam.
- IP Blacklists: An IP address on a blacklist can cause emails to be blocked or sent to spam.
- Warming Up: New domains need to be warmed up slowly by sending emails to engaged users first.
- Personalization: Personalization and correct audience segmentation can improve chances of the email being delivered to the inbox.
Key considerations
- Monitor Sender Reputation: Regularly monitor your sender reputation using tools and services provided by email providers and third-party vendors.
- Implement Email Authentication: Implement SPF, DKIM, and DMARC to authenticate your emails and prevent spoofing.
- Optimize Email Content: Avoid spam trigger words, use clear and concise language, and ensure your email content is relevant and valuable to recipients.
- Improve Recipient Engagement: Encourage recipients to engage with your emails by providing valuable content, segmenting your audience, and personalizing your messages.
- Maintain a Clean Email List: Regularly remove inactive subscribers and invalid email addresses from your list to improve your engagement rates.
- Optimize Email Design: Ensure your emails are properly coded, responsive, and accessible on different devices.
- Check IP Address: Check your IP address against common blacklists and take steps to remove it if necessary.
- Personalization: Ensure you are using the correct 'from' name and address for your email sends.
Marketer view
Email marketer from Constant Contact shares that email content can be a significant factor. Avoid using spam trigger words (e.g., 'free,' 'guaranteed,' 'urgent'), excessive links, or large images without alt text. Ensure your email is properly formatted and accessible on different devices.
30 Jun 2021 - Constant Contact
Marketer view
Email marketer from Moosend explains that your from name and address can make or break your delivery rate. Ensure that you are using the correct details.
21 Aug 2022 - Moosend
What the experts say
7 expert opinions
Lower open rates and spam placement in Gmail stem from multiple factors impacting sender reputation and spam filter triggers. These include issues with email content, placement in tabs other than the inbox, complex Gmail spam calculation, poor list hygiene, negative sender reputation, low recipient engagement, and high complaint rates. Addressing these areas is essential to improving email deliverability.
Key opinions
- Spam Folder Rate: Lower open rates often indicate a higher spam folder rate, suggesting an issue with the email's content.
- Tab Placement: Emails may land in the Updates or Promotions tab, impacting open rates as users interact differently with these tabs.
- Gmail Spam Calculation: Gmail's spam calculation is complex and not solely based on subject lines or links; multiple factors interact in non-linear ways.
- List Hygiene: Poor list hygiene, including sending to old or unengaged addresses, harms sender reputation and deliverability.
- Sender Reputation: A negative sender reputation is a primary driver of emails ending up in spam.
- Engagement Data: Gmail heavily relies on engagement data; low recipient engagement leads to increased spam filtering.
- Complaint Rates: High complaint rates are a significant factor in emails being sent to the spam folder.
Key considerations
- Diagnose Content Issues: Carefully review email content for potential spam triggers, though diagnosing the specific cause can be challenging.
- Monitor Tab Placement: Track email placement across different Gmail tabs to understand how recipients are interacting with your messages.
- Improve List Hygiene: Regularly clean your email list to remove unengaged and invalid addresses.
- Build Sender Reputation: Focus on building a positive sender reputation by sending valuable, relevant content to engaged recipients.
- Encourage Engagement: Create engaging content that encourages recipients to open, click, and interact with your emails.
- Monitor Complaint Rates: Closely monitor complaint rates and take immediate action to address any issues, making unsubscribing easy.
Expert view
Expert from Spam Resource responds that Gmail heavily relies on engagement data. If recipients are not opening or interacting with your emails, Gmail will likely filter them to spam. Encourage engagement by providing valuable content and segmenting your audience.
22 Jun 2024 - Spam Resource
Expert view
Expert from Email Geeks explains that if an email went to spam, you can’t just blame the subject line or a specific link, particularly at Gmail because the way Gmail calculates spam is not a simple a + b + c + d. It’s more like “if a then a+2b, if not a then -b”, meaning certain factors can weigh more than others.
31 May 2022 - Email Geeks
What the documentation says
4 technical articles
Emails are filtered to spam and experience lower open rates in Gmail due to factors identified by Google's spam filtering systems. To improve deliverability, proper email authentication methods like SPF, DKIM, and DMARC are crucial. These protocols help verify the sender's identity, prevent spoofing, and ensure message integrity.
Key findings
- Gmail Spam Signals: Gmail uses various signals, including user reports, sender reputation, and content analysis, to identify and filter spam.
- SPF Records: SPF records specify authorized mail servers for a domain, preventing email address forging and improving deliverability.
- DMARC Protocol: DMARC allows senders to define how receivers should handle emails failing SPF or DKIM, protecting against spoofing and phishing.
- DKIM Signatures: DKIM uses digital signatures to verify sender identity and ensure message integrity, enhancing deliverability and protecting against spoofing.
Key considerations
- Follow Google Guidelines: Adhere to Google's sender guidelines to ensure emails are delivered to the inbox.
- Implement SPF: Implement SPF records to authorize sending mail servers and prevent email forging.
- Implement DMARC: Implement DMARC to define how emails failing authentication should be handled and protect against domain spoofing.
- Implement DKIM: Implement DKIM to digitally sign emails, verifying sender identity and message integrity.
Technical article
Documentation from RFC shares that a Sender Policy Framework (SPF) record is a DNS record that specifies which mail servers are authorized to send email on behalf of your domain. Implementing SPF can help prevent spammers from forging your email address and improve your deliverability.
5 Jan 2023 - RFC
Technical article
Documentation from Microsoft explains that DomainKeys Identified Mail (DKIM) is an email authentication method that uses digital signatures to verify the sender's identity and ensure that the message has not been altered in transit. Implementing DKIM can improve your deliverability and protect your domain from spoofing.
12 Nov 2023 - Microsoft
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