Summary
Poor email sending practices detrimental to deliverability include using purchased or scraped lists (leading to list bombing), neglecting list hygiene (sending to unengaged users, old addresses, and spam traps), employing misleading subject lines, and failing to provide value to subscribers. Technical aspects such as improper email authentication (SPF, DKIM, DMARC), lack of a dedicated or properly warmed-up IP address, and non-compliance with SMTP standards contribute to deliverability issues. Furthermore, ignoring mobile optimization, accessibility, rendering problems, and slow loading times negatively impact user experience and engagement, harming deliverability. Regularly cleaning lists, segmenting audiences, using double opt-in, testing emails, monitoring sender reputation, adhering to platform-specific guidelines (e.g., Outlook.com), and avoiding spam trigger words are essential for maintaining a healthy sender reputation and avoiding spam filters.
Key findings
- List Quality & Acquisition: Purchasing, scraping or poorly acquired email lists damages deliverability through practices like list bombing and hitting spam traps.
- Technical Authentication: Lack of proper email authentication (SPF, DKIM, DMARC) and SMTP standard compliance results in deliverability issues.
- IP Reputation and Warm-Up: Using an unwarmed IP or failing to maintain a positive sender reputation leads to deliverability problems.
- Engagement & User Experience: Poor user experience (lack of mobile optimization, slow loading times) impacts engagement and, in turn, deliverability.
- Proactive List Management: Poor List Hygiene (not removing inactive users) impacts deliverability.
Key considerations
- Ethical List Building: Focus on acquiring subscribers through ethical means, such as double opt-in, and avoid purchasing or scraping lists.
- Implement Authentication: Ensure proper implementation of SPF, DKIM, and DMARC records for all sending domains.
- Monitor and Maintain Reputation: Actively monitor sender reputation, remove unengaged users, and address any deliverability issues promptly.
- Optimize User Experience: Prioritize mobile optimization, accessibility, and fast loading times to enhance user engagement.
- Adhere to Standards: Comply with SMTP standards and platform-specific guidelines (e.g., Outlook.com) to ensure deliverability.
- Perform Testing: Thoroughly test emails across various clients and devices before sending to large audiences.
What email marketers say
10 marketer opinions
Poor email sending practices can significantly harm deliverability. These include using purchased lists, neglecting list hygiene (sending to unengaged users and spam traps), employing misleading subject lines, and failing to provide value to subscribers. Technical aspects like improper email authentication (SPF, DKIM, DMARC), lack of a dedicated IP address, or not warming up an IP address also contribute to deliverability issues. Ignoring mobile optimization, accessibility, and email rendering across different clients negatively impacts user experience and engagement, further affecting deliverability. Regularly cleaning email lists, segmenting audiences, using double opt-in, testing emails, and monitoring sender reputation are essential for avoiding spam filters and maintaining a healthy sender reputation.
Key opinions
- List Quality: Poor list quality (purchased lists, unengaged users, spam traps) severely damages deliverability.
- Authentication: Improperly configured email authentication (SPF, DKIM, DMARC) leads to deliverability problems.
- Engagement: Low engagement (lack of mobile optimization, accessibility issues, slow loading times) negatively affects deliverability.
- IP Warmup: Sending too many emails too soon from a new IP address can cause deliverability issues.
- Sender Reputation: Poor sender reputation (due to spam complaints, sending to spam traps) reduces deliverability.
Key considerations
- List Hygiene: Regularly clean your email list to remove unengaged subscribers and spam traps.
- Authentication Setup: Properly configure SPF, DKIM, and DMARC records for your sending domain.
- IP Warmup Strategy: Gradually increase email volume when using a new IP address.
- Mobile Optimization: Ensure your emails are mobile-friendly and accessible to all users.
- Content Quality: Provide valuable and relevant content to subscribers to encourage engagement.
- Testing: Always test emails across different clients and devices before sending.
Marketer view
Email marketer from a WebmasterWorld forum post shared that a very common problem is using an un-warmed IP and emailing too many people at once and that is very often the root cause of new setup email deliverability problems. Starting with small volumes and building the amount you send up slowly will lead to greater success.
28 Feb 2025 - WebmasterWorld
Marketer view
Email marketer from EmailToolTester writes how not testing emails before you send them can be a huge problem. Emails can look radically different in different email clients and need to be tested properly.
20 Aug 2023 - EmailToolTester
What the experts say
2 expert opinions
Maintaining good email deliverability requires avoiding practices that damage your sender reputation and ensures the ethical handling of email lists. Specifically, avoid 'list bombing' - a tactic of signing up email addresses to numerous services to flood inboxes, which is prevalent in poorly acquired or scraped lists. Crucially, safeguard your IP and domain reputation by preventing practices that lead to spam traps and unengaged users on your email lists.
Key opinions
- List Bombing: Using acquired/scraped lists can lead to 'list bombing,' negatively impacting deliverability.
- Sender Reputation: Poor sending practices harm sender reputation, leading to deliverability issues.
Key considerations
- List Acquisition: Avoid using acquired or scraped email lists to prevent list bombing and other harmful practices.
- Reputation Management: Actively manage and protect your IP and domain reputation by avoiding spam traps and unengaged users.
Expert view
Expert from Word to the Wise shares that Maintaining a good IP and domain reputation is important for deliverability. Practices that harm your reputation, such as sending to unengaged users or spam traps, should be avoided.
16 Mar 2024 - Word to the Wise
Expert view
Expert from Spamresource explains that List bombing is when spammers sign up email addresses for many different services in order to flood the inbox of the victim. Avoiding this tactic on an acquired or scraped list is crucial for maintaining deliverability.
9 Dec 2022 - Spamresource
What the documentation says
5 technical articles
Email deliverability hinges on adherence to established standards, robust authentication methods, and proactive reputation management. Email senders should authenticate emails using SPF, DKIM, and DMARC, maintain low spam complaint rates (below 0.1% as suggested by Google), and avoid sending unsolicited emails. Adhering to SMTP standards detailed by the RFC-Editor, including proper email formatting, is also critical. Providing easy unsubscribe options, monitoring sender reputation, and sending relevant content are equally important for maintaining good deliverability. Compliance with specific platform requirements, such as those outlined by Microsoft for Outlook.com, including setting up reverse DNS records and monitoring complaint rates, can further minimize deliverability issues.
Key findings
- Authentication: Email authentication (SPF, DKIM, DMARC) is crucial for verifying sender identity.
- Spam Rates: Maintaining low spam complaint rates is essential for good deliverability.
- SMTP Standards: Adhering to SMTP standards and proper email formatting is necessary.
- Platform Compliance: Compliance with specific platform requirements (e.g., Outlook.com guidelines) improves deliverability.
- User Control: Providing clear unsubscribe options and relevant content is important for user engagement and deliverability.
Key considerations
- Authentication Implementation: Implement SPF, DKIM, and DMARC records for your sending domain.
- Spam Monitoring: Monitor spam complaint rates and take steps to reduce them.
- Standards Compliance: Ensure your emails comply with SMTP standards and proper formatting guidelines.
- Platform Guidelines: Familiarize yourself with and adhere to specific email platform guidelines (e.g., Microsoft's Outlook.com requirements).
- Content Relevance: Focus on sending relevant, valuable content to keep subscribers engaged and reduce spam complaints.
- Unsubscribe Accessibility: Make the unsubscribe process simple and easily accessible to subscribers.
Technical article
Documentation from Mailjet explains that avoiding spam trigger words, providing a clear unsubscribe link, and monitoring your sender reputation are vital for maintaining good deliverability. Sending relevant content to engaged subscribers is also key.
21 Sep 2022 - Mailjet
Technical article
Documentation from RFC-Editor details SMTP standards, including proper formatting of email headers and message bodies. Non-compliance with these standards can lead to deliverability issues.
19 Aug 2024 - RFC-Editor
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