Summary
When using Klaviyo's shared IP addresses, email deliverability to Gmail can sometimes face unexpected challenges. Issues like significant drops in open rates and emails landing in spam folders, despite stable performance with other email clients, indicate that Gmail's unique filtering mechanisms may be at play. Unlike some other mailbox providers, Gmail heavily prioritizes domain reputation over IP reputation, making your sending domain's health paramount. Shared IP infrastructure can introduce complexities, as the sending behavior of other users on the same IP can indirectly influence your deliverability, especially if they engage in practices that lead to blocklistings or poor sender scores.
Key findings
- gmail's focus on domain: Gmail's filtering predominantly relies on domain reputation rather than shared IP reputation, which is often less impactful.
- user engagement is critical: Recipient actions and engagement (or lack thereof) directly inform Gmail's machine learning filters, influencing where your emails land (inbox vs. spam).
- hidden reputational factors: Beyond the sending domain, the reputation of other domains linked within your email content (e.g., CDN, image hosting) can affect deliverability.
- authentication is key: Proper email authentication (SPF, DKIM, DMARC) is foundational for establishing trust with Gmail and preventing your emails from being flagged as suspicious.
- shared domain abuse: If a shared return-path (SPF) or DKIM domain is misused by one or two clients on a shared platform, it can negatively impact all others using that domain.
Key considerations
- monitor domain reputation: Actively use tools like Google Postmaster Tools to track your domain's reputation, spam rate, and authentication status specifically for Gmail.
- check all linked domains: Routinely verify the reputation of all domains embedded within your email content, including those used for images, tracking, or other hosted assets, as a poor reputation can affect your email placement.
- review recipient engagement: Analyze engagement metrics beyond opens, such as clicks and conversions, to understand how recipients are interacting with your emails and if their actions are inadvertently signaling disinterest to Gmail.
- assess authentication setup: Ensure your email authentication records (SPF, DKIM, DMARC) are correctly configured and aligned with your sending domain to establish sender trust.
- consider list hygiene: Regularly clean your email lists to remove unengaged subscribers, inactive addresses, and potential spam traps to maintain a healthy sender reputation. Poor list hygiene can lead to sudden drops in deliverability.
What email marketers say
Email marketers often find themselves grappling with the nuances of deliverability, particularly when using shared IP addresses from platforms like Klaviyo. A common sentiment is frustration with support teams when facing sudden drops in Gmail deliverability, as the responses often feel generic. Marketers typically look for external factors like new Google policies or shared IP blacklisting, but community discussions reveal that issues are frequently rooted in how Gmail perceives their domain and recipient engagement.
Key opinions
- gmail-specific drops are common: A notable drop in Gmail open rates, even if other clients are stable, is a recurring concern for marketers on shared IPs, suggesting Gmail's distinct filtering algorithms.
- shared ip not always the culprit: Despite initial suspicions, shared IP infrastructure is often less of a direct cause for Gmail deliverability issues compared to domain reputation.
- support limitations: Marketers frequently report feeling unsupported by ESPs (like Klaviyo) when facing deliverability issues, citing generic responses that don't address specific problems.
- revenue impact: Significant drops in email-driven revenue are a clear indicator that emails are not reaching the inbox effectively, confirming deliverability problems beyond just open rates.
Key considerations
- verify spam placement directly: Conduct spot checks with real users to confirm whether emails are indeed landing in the spam folder, providing direct evidence of deliverability issues.
- check authentication and domain setup: Even on shared IPs, ensure your domain's SPF, DKIM, and DMARC records are correctly set up and aligned, as these are crucial for Gmail trust.
- examine content and linked domains: Review if recent changes to content, links, or third-party hosting (like CDNs) might be impacting your domain's reputation with Gmail. Learn more about why Gmail flags messages as suspicious.
- leverage external tools: Utilize free email testing tools that can provide insights into your domain's health and potential issues specific to Gmail.
- understand shared ip impact: While shared IPs offer advantages, understand that reputation issues from other senders can still have a spillover effect on your deliverability, even if Gmail primarily focuses on domain reputation.
Marketer view
Email marketer from Email Geeks states that their open rates for iCloud, Hotmail, and Outlook remained stable from October to January, but Gmail's open rates experienced a significant decline. This indicates that the problem is specific to Gmail, rather than a general deliverability issue across all email clients. The disproportionate impact on Gmail suggests that Google's filtering algorithms might be reacting to specific sending patterns or content elements.
Marketer view
Email marketer from Email Geeks reveals that direct spot checks with people in their sales funnel confirmed emails were consistently landing in spam folders for Gmail recipients. This direct feedback aligns with the observed drop in open rates and indicates a serious deliverability problem. Consequently, revenue from emails has decreased by 12 percentage points, highlighting a tangible financial impact from the deliverability issues.
What the experts say
Deliverability experts generally agree that Gmail's algorithms prioritize domain reputation and user engagement over shared IP reputation. They emphasize that while shared IPs can introduce complexities, Google's sophisticated machine learning filters are adept at segmenting traffic and selectively blocking mail based on sender behavior. Sudden drops in deliverability, even if isolated to Gmail, are often a symptom of underlying issues with recipient reactions, domain configuration, or even the reputation of linked content domains.
Key opinions
- domain over ip: Gmail primarily evaluates email based on domain reputation, not the shared IP address. This allows Gmail to selectively block or filter emails even on large shared sending pools.
- recipient actions drive filtering: Recipient behavior (e.g., opens, clicks, deleting without opening, marking as spam) is a powerful signal to Gmail's machine learning, directly influencing inbox placement.
- linked content reputation: Domains used for content delivery networks (CDNs) or image hosting within an email can carry their own reputation, and a negative reputation here can impact deliverability.
- shared domain authentication: Issues can arise if shared return-path (SPF) or DKIM domains are compromised or abused by other senders, affecting all clients using that domain.
- dkim replay attacks: Recent DKIM replay attacks have been observed to negatively affect domain reputation in Google Postmaster Tools.
- volume changes and delays: Sudden changes in email volume can lead to delays, which might precede a drop in Gmail opens and increased spam placement.
Key considerations
- assess permission practices: Review how email permissions are being collected, as poor consent practices can lead to lower engagement and higher spam complaints.
- verify authentication setup: Ensure that SPF, DKIM, and DMARC are properly configured and aligned for your sending domain, as these are critical for establishing sender legitimacy with Gmail. Explore a simple guide to DMARC, SPF, and DKIM.
- utilize google postmaster tools: Routinely check Google Postmaster Tools (GPT) for insights into your domain's reputation, spam rate, and authentication errors, as it offers direct feedback from Gmail.
- audit content links: Scrutinize all linked domains within your email content (e.g., images, tracking pixels, landing pages) for any reputation issues that could be affecting deliverability.
- monitor engagement metrics closely: Beyond open rates, track clicks, conversions, and even complaint rates. Gmail's filters heavily weigh how recipients interact with your emails.
Expert view
Email expert from Email Geeks explains that Gmail's filtering mechanisms primarily focus on domain reputation rather than IP reputation, even for shared infrastructures. This means that Gmail is highly effective at selectively blocking emails based on specific sender domains, regardless of the shared IP they originate from. Therefore, focusing on domain health is crucial for Gmail deliverability.
Expert view
Email expert from Email Geeks suggests that if deliverability was good and then deteriorated, the primary cause is likely how recipients are interacting with emails. Recipient actions, or inactions, provide strong signals to Gmail's machine learning engine, which then decides whether to place emails in the inbox or the bulk (spam) folder. This highlights the importance of engagement in Gmail's filtering process.
What the documentation says
Official documentation and technical guides from major mailbox providers like Google, and platforms like Klaviyo, underscore the paramount importance of domain reputation and comprehensive email authentication for deliverability. While shared IPs are a common starting point, the focus quickly shifts to the sender's specific domain health. Documentation consistently advises on monitoring engagement, ensuring correct DNS records (SPF, DKIM, DMARC), and understanding how linked content can influence email filtering decisions.
Key findings
- domain alignment: Documentation consistently emphasizes that your sender email address's root domain must match the domain used for authentication (SPF/DKIM) for optimal deliverability.
- authentication is foundational: Proper setup of SPF, DKIM, and DMARC is highlighted as crucial for establishing sender identity and trust with Gmail and other providers, reducing the likelihood of being flagged as spam.
- gmail's internal visibility: Klaviyo's documentation notes that they have no visibility into how inbox providers like Gmail sort an email once it has been delivered, emphasizing the mailbox provider's autonomous filtering.
- dmarc compliance: For emails to pass DMARC and avoid 'suspicious' warnings, proper configuration and alignment are required, which is a key factor for personal inboxes.
- link reputation: Suspicious links, even those within a Klaviyo wrapper, can trigger warnings and impact deliverability.
Key considerations
- prioritize domain setup: Focus on setting up your sending domain correctly with your ESP, ensuring full domain alignment as a primary step for better deliverability.
- implement authentication: Ensure your SPF, DKIM, and DMARC records are always correctly configured. Google Postmaster Tools provides insights into your authentication status.
- review content for suspicious links: Regularly audit your email content for any unusual or blacklisted links, including those from third-party services like CDNs. Klaviyo documentation mentions this directly in their deliverability FAQ.
- understand shared ip dynamics: While shared IPs can minimize the need for re-warming, be aware that their reputation is collective. Understand that Google and Yahoo's new sender requirements emphasize domain authentication over IP address.
- leverage postmaster tools: Utilize Google Postmaster Tools to gain crucial insights into your email performance and reputation with Gmail specifically.
Technical article
Documentation from Klaviyo Help Center on deliverability FAQs indicates that a suspicious link, even if embedded within the Klaviyo wrapper, can lead to warnings and impact email deliverability. This highlights the importance of scrutinizing all URLs within your email content, including those from third-party services, to ensure they do not carry a negative reputation that could trigger spam filters.
Technical article
Documentation from Klaviyo Help Center on understanding email authentication states that if a user sees a DMARC warning for a personal, non-enterprise inbox, it is highly probable that DMARC is failing. To achieve DMARC compliance, proper configuration and alignment of SPF and DKIM records are essential, as this verifies sender authenticity and builds trust with mailbox providers like Gmail.
Related resources
15 resources
Related pages
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