Summary
Experts, marketers, and documentation consistently indicate that IP certification is no longer a primary driver of email deliverability. The focus has shifted to building a strong sender reputation through proper email authentication (SPF, DKIM, DMARC), consistent sending practices, engaging content, maintaining clean email lists, and actively managing spam complaints. Mailbox providers prioritize sender reputation based on user engagement and data-driven filtering over IP certification. Successfully warming up IPs and organic list building are also much more important.
Key findings
- Decreased Importance: The importance of IP certification has diminished as mailbox providers prioritize sender reputation.
- No Guarantee of Inbox Placement: IP certification programs do not guarantee inbox placement.
- Reputation is Paramount: Building a strong sender reputation is more critical than IP certification.
- Authentication is Key: Email authentication (SPF, DKIM, DMARC) is essential for establishing sender legitimacy.
- Engagement Drives Deliverability: User engagement with email content is a major factor in determining sender reputation and deliverability.
Key considerations
- Warm Up IPs: Properly warm up new IPs to establish a positive sending reputation.
- Practice List Hygiene: Maintain clean email lists by removing inactive or invalid addresses.
- Create Valuable Content: Focus on creating engaging and relevant content that resonates with your audience.
- Monitor Reputation: Actively monitor your sender reputation metrics to identify and address any issues promptly.
- Implement Authentication: Ensure correct implementation of SPF, DKIM, and DMARC to authenticate your emails and prevent spoofing.
- Build Email Lists Organically: Build email lists organically.
What email marketers say
8 marketer opinions
The consensus among email marketers is that IP certification is not a primary factor for email deliverability in today's email ecosystem. While it may offer a small benefit, it's not a substitute for building a strong sender reputation through proper email authentication (SPF, DKIM, DMARC), consistent sending volume, engaging content, maintaining clean email lists, and proactively managing spam complaints. Modern mailbox providers prioritize sender reputation based on engagement metrics over IP certification.
Key opinions
- Diminished Importance: IP certification's value has decreased as mailbox providers now focus on sender reputation based on engagement and authentication.
- No Guarantee: IP certification programs do not guarantee inbox placement.
- Reputation is Key: Building a strong sender reputation is more critical than IP certification.
- Authentication Matters: Proper email authentication (SPF, DKIM, DMARC) plays a significant role in deliverability.
- Engagement Drives Deliverability: User engagement with email content is a major factor in sender reputation and deliverability.
Key considerations
- Warm Up IPs: Properly warm up your IPs to establish a sending reputation.
- Maintain Clean Lists: Regularly clean your email lists to remove inactive or invalid addresses.
- Send Engaging Content: Focus on creating valuable and relevant content to drive user engagement.
- Monitor Reputation: Actively monitor your sender reputation metrics to identify and address any issues.
- Authenticate Email: Implement SPF, DKIM, and DMARC to authenticate your email and protect against spoofing.
Marketer view
Email marketer from GlockApps goes into details on how to imporve your IP reputation. They state, warm up your IP, clean email lists, consistent volume, authentication and monitor sender reputation. IP Certification is not mentioned.
13 Aug 2024 - GlockApps
Marketer view
Email marketer from Return Path (via EmailDeliverability.com) stresses that building a strong sender reputation through consistent sending volume, proper authentication, and high engagement rates is more critical for email deliverability than obtaining IP certification.
4 Jan 2025 - EmailDeliverability.com
What the experts say
3 expert opinions
Experts generally agree that IP certification is not as important for email deliverability as it once was. The email landscape has evolved, with mailbox providers placing more emphasis on sender reputation built through authentication (SPF, DKIM, DMARC), user engagement, and data-driven filtering. While whitelists exist, focusing on building a positive reputation is crucial.
Key opinions
- Declining Importance: IP certification is not as vital as it used to be for inbox placement.
- Reputation Matters Most: Sender reputation significantly impacts email placement.
- Authentication is Key: Modern authentication methods (SPF, DKIM, DMARC) are crucial for establishing legitimacy.
- Engagement is a Factor: User engagement with emails influences deliverability.
Key considerations
- Build Reputation: Focus on building a strong sender reputation through consistent, high-quality email practices.
- Implement Authentication: Ensure proper implementation of SPF, DKIM, and DMARC for email authentication.
- Prioritize Engagement: Create engaging content that encourages positive user interactions.
- Monitor Performance: Track deliverability metrics and adjust strategies accordingly.
Expert view
Expert from Spam Resource explains that while IP certification programs like Bonded Sender existed, the industry has largely moved towards more sophisticated methods of sender authentication (SPF, DKIM, DMARC) and reputation management based on user engagement and data-driven filtering. IP certification is not as effective as modern reputation systems.
9 Jan 2024 - Spam Resource
Expert view
Expert from Word to the Wise discusses that your reputation will influence where your mail is placed. Some mailbox providers have a white list, but building your reputation is still far more important.
4 Mar 2025 - Word to the Wise
What the documentation says
4 technical articles
Official documentation from Google, Microsoft, and RFC regarding email standards emphasizes sender reputation, authentication (SPF, DKIM, DMARC), list hygiene, content quality, and user engagement as key factors for email deliverability. IP certification is not explicitly mentioned or prioritized in these guidelines, suggesting it's not considered a critical element for inbox placement.
Key findings
- Authentication Priority: Email authentication (SPF, DKIM, DMARC) is consistently highlighted as essential for deliverability.
- Reputation Emphasis: Sender reputation is a critical factor influencing inbox placement.
- Engagement Matters: User engagement with email content significantly impacts deliverability.
- Certification Unmentioned: IP certification is not mentioned as a key factor in official documentation from major mailbox providers and standards bodies.
- List Hygiene: List hygiene (removing invalid addresses) is important for deliverability.
Key considerations
- Implement SPF, DKIM, DMARC: Ensure proper implementation of SPF, DKIM, and DMARC for email authentication.
- Maintain List Hygiene: Regularly clean your email lists to remove inactive or invalid addresses.
- Create Engaging Content: Focus on creating valuable and relevant content to drive user engagement.
- Monitor Sender Reputation: Actively monitor your sender reputation metrics to identify and address any issues.
- Comply with Guidelines: Adhere to sender guidelines provided by mailbox providers like Google and Microsoft.
Technical article
Documentation from DMARC.org goes into technical detail about the DMARC protocol, but shows it is far more important to implement this than IP certification.
30 Jan 2025 - DMARC.org
Technical article
Documentation from Google Postmaster Tools outlines sender guidelines that focus on email authentication (SPF, DKIM, DMARC), maintaining low spam complaint rates, and providing valuable content to drive engagement. IP certification is not mentioned as a significant factor for deliverability to Gmail users.
25 Mar 2025 - Google Postmaster Tools
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