Achieving optimal email deliverability and avoiding spam filters involves a comprehensive strategy addressing technical configuration, list management, content creation, and reputation monitoring. While there's no magic bullet, fundamental practices include building a clean, engaged email list through double opt-in and regular cleaning, implementing SPF, DKIM, and DMARC for email authentication, segmenting lists for targeted content, maintaining a consistent sending schedule, avoiding spam trigger words, optimizing for mobile and accessibility, using a dedicated IP (especially for high-volume sending), proactively verifying email addresses, setting up feedback loops, and monitoring blocklists. Furthermore, positive engagement metrics significantly improve deliverability.
10 marketer opinions
To optimize email deliverability and avoid spam filters, several best practices should be followed. These include building and maintaining a clean email list with double opt-in and regular cleaning, authenticating emails using DKIM, SPF, and DMARC, segmenting lists for targeted content, maintaining a consistent sending schedule, avoiding spam trigger words, optimizing emails for mobile devices and accessibility, using a dedicated IP address for high-volume sending, verifying email addresses, and setting up feedback loops to handle spam complaints.
Marketer view
Email marketer from Sendinblue shares that improving sender reputation requires consistent sending volume, avoiding spam traps, and authenticating emails with DKIM, SPF, and DMARC.
28 Aug 2023 - Sendinblue
Marketer view
Email marketer from Litmus shares that making emails accessible to all recipients, including those with disabilities, not only improves inclusivity but also enhances deliverability by signaling a commitment to best practices.
23 Oct 2023 - Litmus
9 expert opinions
Achieving email deliverability and avoiding spam filters requires a multifaceted approach. There's no single magic solution, but generally, avoiding spam-like behavior is key. Mailbox providers use algorithms, including 'trusted reporters,' to identify spam and also track engagement metrics like opens and clicks to determine email value. Monitoring IP addresses against blocklists, warming up new IPs by gradually increasing sending volume, and focusing on sending wanted content can also improve deliverability. Platforms like Hotmail also have trusted reporter programs and actively ask users about spam classification accuracy.
Expert view
Expert from Word to the Wise (Laura Atkins) explains that positive engagement metrics, such as opens and clicks, signal to mailbox providers that recipients find your emails valuable, thus improving deliverability.
23 May 2022 - Word to the Wise
Expert view
Expert from Email Geeks shares that Hotmail has a trusted reporter program for the best reporters.
23 Sep 2022 - Email Geeks
4 technical articles
Email authentication is critical for deliverability. SPF records specify authorized mail servers for a domain. DKIM adds a digital signature to emails, verifying sender identity and message integrity. DMARC policies use SPF and DKIM to protect against spoofing and phishing. Reverse DNS lookup (PTR records) maps IP addresses to domain names, verifying server legitimacy.
Technical article
Documentation from RFC explains that reverse DNS lookup (PTR record) maps an IP address to a domain name, verifying the legitimacy of the sending server and preventing spammers from using forged IP addresses.
18 Jan 2024 - RFC Editor
Technical article
Documentation from DMARC.org defines DMARC as a policy that allows senders to indicate that their emails are protected by SPF and DKIM, and tells receivers what to do if authentication fails, helping to prevent email spoofing and phishing.
8 Apr 2024 - DMARC.org
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