Summary
Outreach emails often land in spam due to a complex interplay of factors impacting sender reputation, content, and technical configuration. Sending prospecting emails to purchased or researched lists is often flagged as spam. Gmail identifies emails based on content similarity to previously marked spam. Authentication issues, specifically the lack of or improper setup of SPF, DKIM, and DMARC, are major contributors. Maintaining list hygiene, gradually warming up IP addresses, managing sending volume, and avoiding spam trigger words are crucial. Monitoring domain reputation using tools like Google Postmaster Tools and setting up feedback loops with ISPs are essential for identifying and addressing issues.
Key findings
- Prospecting Practices: Sending emails to purchased or scraped lists significantly increases the risk of being marked as spam.
- Content Analysis: Email providers analyze content for similarities to known spam, impacting deliverability.
- Authentication Protocols: Proper implementation of SPF, DKIM, and DMARC is critical for establishing sender legitimacy.
- Sender Reputation: A positive sender reputation is built over time through consistent, legitimate sending practices.
- Volume Management: Managing sending volume and gradually warming up IP addresses prevent triggering spam filters.
Key considerations
- Email List Quality: Focus on building an organic email list and regularly removing inactive subscribers.
- Content Optimization: Craft engaging, personalized content that avoids spam trigger words.
- Technical Setup: Ensure correct configuration and validation of SPF, DKIM, and DMARC records.
- Reputation Monitoring: Actively monitor your domain's reputation using Google Postmaster Tools and other relevant tools.
- Feedback Loop Implementation: Set up feedback loops (FBLs) with major ISPs to monitor spam complaints and improve deliverability.
- Gradual IP Warmup: When using a new IP address, gradually increase sending volume to establish trust.
- Personalization: Personalize your email to each user based on their interests and profile data.
- Previewing Email: Always preview your email in multiple email clients to ensure the email looks correct on all platforms.
What email marketers say
10 marketer opinions
Outreach emails often land in spam due to factors impacting sender reputation. Key strategies to improve deliverability include warming up your IP address by gradually increasing sending volume, authenticating emails using SPF, DKIM, and DMARC, and consistently cleaning email lists by removing inactive subscribers. Avoiding spam trigger words in subject lines and email content, using a dedicated IP address carefully, A/B testing email elements, previewing emails across clients, encouraging whitelisting, personalizing content, and using custom tracing domains are also crucial.
Key opinions
- IP Warm-up: Gradually warm up your IP address to build a positive sender reputation and avoid being flagged as spam.
- Email Authentication: Implement SPF, DKIM, and DMARC to authenticate your emails and verify your sending legitimacy.
- List Hygiene: Regularly clean your email lists by removing inactive or unsubscribed contacts to maintain a high engagement rate.
- Spam Trigger Words: Avoid using common spam trigger words in your subject lines and email body to bypass spam filters.
- Personalization: Personalize email content and subject lines using subscriber data to increase relevance and engagement.
Key considerations
- Sending Volume: Monitor and adjust your sending volume to avoid triggering spam filters, especially when using a new IP address.
- Dedicated IP: Carefully manage and monitor a dedicated IP address to maintain a good sender reputation.
- A/B Testing: Continuously A/B test different subject lines and email content to optimize for engagement and deliverability.
- Email Preview: Preview how your emails render across different email clients to identify and fix potential formatting issues.
- Whitelisting: Encourage subscribers to add your email address to their address book or whitelist to ensure inbox placement.
- Tracing Domains: Consider using custom tracing domains to improve email deliverability.
Marketer view
Email marketer from Sendinblue shares that improving sender reputation involves authenticating your emails with SPF, DKIM, and DMARC, keeping your email lists clean, and avoiding spam trigger words.
17 Mar 2025 - Sendinblue
Marketer view
Email marketer from Email Geeks shares to try to stop your outreach for week or two. After that period start with slow sending. Using custom tracing domains is also something that can help you
6 Feb 2022 - Email Geeks
What the experts say
7 expert opinions
Outreach emails often go to spam due to a combination of factors including sending practices, content, and sender reputation. Sending prospecting emails to purchased lists can be flagged as spam by filters. Gmail identifies emails as spam based on content similarity to previously marked spam. Both content and sender reputation matter; even non-spammy content can be filtered if the sender's reputation is low. Correctly setting up SPF, DKIM, and DMARC is essential for authentication. Monitoring sending volume is crucial, as high volumes can trigger spam filters, especially during IP warm-up. Tools like Google Postmaster Tools can help monitor domain reputation and identify issues such as spam complaints and high bounce rates.
Key opinions
- Prospecting Lists: Sending to purchased or researched lists often results in emails being flagged as spam.
- Content Similarity: Gmail and other providers identify spam based on content similarity to previously marked spam messages.
- Holistic Reputation: Sender reputation is determined by sending practices, list quality, and infrastructure.
- Authentication: Proper authentication (SPF, DKIM, DMARC) is essential for email deliverability.
- Sending Volume: High sending volumes, especially during IP warm-up, can trigger spam filters.
Key considerations
- Sending Practices: Evaluate and refine current sending practices to avoid being perceived as a spammer.
- List Quality: Prioritize building an organic list to avoid being marked as spam.
- Content Review: Review and refine content to avoid using spam-like language or structure.
- Authentication Setup: Ensure proper setup and validation of SPF, DKIM, and DMARC records.
- Volume Monitoring: Monitor sending volume and adjust as needed, especially when warming up new IPs.
- Reputation Monitoring: Use tools like Google Postmaster Tools to actively monitor your domain's reputation.
Expert view
Expert from Word to the Wise explains that content is only part of the issue and reputation also plays a large role. If your reputation is low (due to sending practices, list quality, or infrastructure problems), even non-spammy content can land in the spam folder.
7 Feb 2025 - Word to the Wise
Expert view
Expert from Spamresource.com responds to monitor your domain's reputation using tools like Google Postmaster Tools. This helps identify issues like spam complaints, high bounce rates, and authentication failures.
31 Mar 2024 - Spamresource.com
What the documentation says
5 technical articles
Outreach emails often land in spam due to issues addressed by adhering to documented best practices. Google emphasizes following bulk sender guidelines, proper authentication, and bounce rate management. Microsoft advocates using the Junk Email Reporting Program (JMRP) and Sender ID. Implementing SPF records as per RFC standards helps verify sending authorization. DMARC aids in handling authentication failures and preventing spoofing. SparkPost highlights the importance of setting up feedback loops with ISPs to monitor spam complaints and sender reputation.
Key findings
- Google Guidelines: Following Google's bulk sender guidelines ensures better inbox placement in Gmail.
- Microsoft JMRP: Using the Junk Email Reporting Program helps improve deliverability to Outlook users.
- SPF Records: Implementing SPF records verifies sending authorization and prevents spoofing.
- DMARC Compliance: DMARC helps handle authentication failures and protects against domain spoofing.
- Feedback Loops: Setting up feedback loops with ISPs enables monitoring of spam complaints.
Key considerations
- Bulk Sender Compliance: Ensure compliance with Google's bulk sender guidelines.
- JMRP Implementation: Participate in Microsoft's Junk Email Reporting Program.
- SPF Configuration: Properly configure and validate SPF records.
- DMARC Deployment: Deploy and monitor DMARC policies to protect against spoofing.
- FBL Setup: Establish feedback loops with major ISPs to monitor spam complaints.
Technical article
Documentation from RFC explains that implementing Sender Policy Framework (SPF) records in your DNS settings helps verify that you are authorized to send emails on behalf of your domain, preventing spoofing and improving deliverability.
27 Mar 2023 - RFC
Technical article
Documentation from Google Workspace Admin Help states that following Google's bulk sender guidelines, including proper authentication and managing bounce rates, is essential for ensuring your emails reach Gmail inboxes.
27 Oct 2023 - Google Workspace Admin Help
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