Summary
Migrating to a new domain and Email Service Provider (ESP) can often lead to a temporary drop in email inbox placement, with many messages unexpectedly landing in spam folders. This typically happens because mailbox providers (ISPs) need time to establish a new sender reputation for the domain and the new sending infrastructure. Unlike established domains, a new domain lacks historical sending data and trust, causing ISPs to treat its initial emails with higher scrutiny.
Key findings
- New domain status: A domain used for email sending for the first time starts with no established reputation, leading to heightened scrutiny from spam filters.
- Infrastructure change: Switching ESPs means using new sending IP addresses, which also require a new reputation to be built with ISPs.
- Content impact: Even with new infrastructure, poor content practices (e.g., insecure links, large images) can significantly contribute to spam placement.
- Initial testing: Mailbox providers often test new senders by initially directing some emails to the spam folder to gauge recipient engagement and reactions.
- Seed list limitations: Inbox placement testing tools may not offer comprehensive coverage for all mailbox providers or B2B spam filters.
Key considerations
- Email warmup: Implement a structured email warmup plan to gradually increase sending volume on the new domain and IP addresses. For more details, see what causes emails to go to spam.
- Authentication setup: Verify that SPF, DKIM, and DMARC records are correctly configured for your new domain and ESP to ensure proper authentication.
- Content audit: Rigorously review email content for anything that might trigger spam filters, such as insecure HTTP links or overly large images.
- Monitor metrics: Beyond seed tests, closely monitor actual engagement metrics (opens, clicks) and use tools like Google Postmaster Tools. This Kickbox guide on sender reputation offers more insights.
- Reputation building: Understand that building a positive sender reputation for a new domain and ESP takes time and consistent good sending practices.
What email marketers say
Email marketers frequently encounter similar challenges when migrating sending infrastructure or introducing a new domain. Their experiences highlight common issues such as inconsistencies in testing tools, the persistent influence of email content on deliverability, and the psychological impact of seeing fluctuating spam rates, even when broader metrics might suggest otherwise.
Key opinions
- Testing tool accuracy: Many marketers find that seed list tools like GlockApps may not provide a complete or accurate picture, especially for B2B audiences with specialized spam filters like Proofpoint.
- Content persistence: Despite a new domain and ESP, recurring spam issues often point back to problematic content elements, such as insecure HTTP links or excessively large images.
- Initial volatility: It's common for inbox placement rates to fluctuate significantly week-to-week during the initial setup and testing phase of a new domain.
- Existing issues: Low open and click rates on an old sending system can indicate underlying deliverability problems that might carry over, even if not directly affecting the new domain's reputation.
- Overwhelm: The complexity of diagnosing and resolving deliverability issues, especially during migration, can be overwhelming for marketers.
Key considerations
- Holistic view: Do not rely solely on seed list testing; combine these insights with actual engagement data (if available) and Postmaster Tools data to diagnose deliverability drops.
- Content hygiene: Proactively audit your email HTML for any insecure links or excessively long URLs. Consider optimizing image sizes before sending.
- Audience specifics: Be aware that B2B audiences may have different spam filtering mechanisms than B2C, impacting how testing tools perform.
- Gradual ramp-up: Acknowledge that building trust with a new domain takes time and a gradual sending approach is more effective than sudden bulk sends. Find out how to avoid spam folders.
Marketer view
Email marketer from Email Geeks notes that their corporate email is also on a 'cousin domain' and is already experiencing spam folder placement. This suggests a broader, possibly pre-existing deliverability challenge affecting their entire email ecosystem, not just the newly introduced main domain. The consistency of spam issues across multiple domains, even related ones, indicates that the underlying problem might extend beyond simple domain reputation.
Marketer view
A marketer from Email Geeks explains their audience comprises Certified Public Accountants (CPAs), a mix of B2C and B2B contacts. This diversity means recipients use both corporate and personal email addresses. Understanding this split is important because B2B email environments often have stricter spam filters and different deliverability expectations compared to consumer mailboxes.
What the experts say
Email deliverability experts offer critical technical insights and strategic advice for navigating the complexities of migrating email sending. Their perspectives often focus on the underlying mechanisms of how mailbox providers assess senders, the limitations of testing tools, and the importance of a well-executed warmup process. They emphasize that initial spam placement is often a diagnostic phase for new infrastructure.
Key opinions
- Corporate email impact: If corporate email resides on the parent domain, high volumes from individual senders (e.g., sales) can negatively affect overall domain reputation.
- Content flags: Insecure HTML elements, like http: links, and large image sizes are common content-related triggers for spam filters.
- Consistency: If a new domain and ESP face the same deliverability problems as previous setups, the core issue likely lies within the email content or list quality.
- Test email behavior: Using generic subject lines like 'test' for seed list testing can inadvertently trigger spam filters, especially with providers like Google.
- Warmup necessity: Moving to new infrastructure or a new domain almost always results in temporary bulk folder placement until the filters adjust and learn sender behavior. Read about retaining sender reputation.
- Engagement thresholds: Experts typically expect Gmail open rates of 15-20% for promo tab placement and 30-50% for inbox tab placement. Lower rates often indicate spam foldering.
Key considerations
- Internal sending audit: Work with IT to monitor individual sender volumes on corporate domains, especially for sales teams, to prevent unintentional damage to overall domain reputation.
- Content optimization: Prioritize updating all links to HTTPS and compressing images to reduce email size, which can improve inbox placement.
- Warmup strategy: Ensure a proper warmup process is implemented for both the new infrastructure and the main domain. Expect some initial spam foldering as a normal part of this phase. This is key when rebranding with a new domain.
- Engagement analysis: If open and click rates are consistently low on your existing system, it's a strong indicator of deliverability problems that need addressing, regardless of a new migration. Mailjet offers guidance on avoiding spam filters.
- Seed test interpretation: Recognize that inbox testing tools provide directional data and may not fully reflect real-world inbox placement, especially during the initial reputation-building phase.
Expert view
Expert from Email Geeks suggests determining if corporate email is sent from the same parent domain. This is important because internal email practices can influence the overall domain reputation. A compromised or poorly managed corporate email setup could inadvertently affect marketing email deliverability from the same domain.
Expert view
Expert from Email Geeks recommends that IT investigate the sending volumes of individual corporate senders, particularly those in sales, if corporate email shares the parent domain. If these individuals send over 100 messages per day, it could be seen as unusual behavior by ISPs. Such high volumes from personal mailboxes can negatively impact the domain's reputation, potentially affecting marketing sends.
What the documentation says
Official documentation from mailbox providers and email industry bodies consistently outlines technical standards and best practices for email sending, especially for new entities. These guidelines emphasize the importance of identity verification, controlled sending behavior, and content quality. They provide the foundational rules that dictate how emails are processed and whether they reach the inbox or the spam folder.
Key findings
- Initial reputation: New sending domains and IPs start with an unknown or neutral reputation, meaning ISPs will scrutinize traffic more heavily until trust is earned.
- Authentication as foundation: Proper configuration of SPF, DKIM, and DMARC is universally considered fundamental for proving sender legitimacy and preventing spoofing. For a simple guide to DMARC, SPF, and DKIM, check our resource.
- Volume control: Gradual, consistent increases in sending volume (warmup) are consistently recommended to allow ISPs to observe and build a positive sending history.
- Engagement feedback: Recipient engagement (opens, clicks, positive replies) and lack of negative feedback (complaints, bounces) are crucial signals for reputation building.
- Content guidelines: Adhering to content best practices, avoiding spammy keywords, suspicious links, and excessive images, is vital for inbox delivery.
Key considerations
- DNS records: Ensure all necessary DNS records for email authentication (SPF, DKIM, DMARC) are correctly published and aligned with your new domain and ESP settings.
- Warmup schedule: Strictly follow recommended warmup schedules provided by your new ESP or general industry guidelines, gradually increasing volume and maintaining engagement.
- Feedback loop enrollment: Enroll in feedback loops (FBLs) with major ISPs to receive notifications of recipient complaints, allowing for prompt list hygiene.
- Utilize Postmaster Tools: Leverage tools like Google Postmaster Tools to track domain reputation, spam rates, and authentication errors in real-time. Our ultimate guide to Google Postmaster Tools offers more help.
- Consistent monitoring: Continuously monitor deliverability metrics and adjust sending practices as needed to maintain a healthy sender reputation. Mailchimp has resources on avoiding spam filters.
Technical article
Documentation from Mailchimp indicates that spam filters are highly adaptive, constantly evolving based on user preferences and feedback. If multiple recipients mark an email as spam, this collective negative action directly influences future inbox placement. This highlights the importance of maintaining high subscriber engagement and minimizing complaints to avoid being broadly flagged.
Technical article
Mailjet documentation advises ensuring that the website linked to your email address is active and fully functional. They state that sending email from an address connected to an inactive or blank website will make ISPs suspicious. This points to the interconnectedness of online presence and email reputation, emphasizing the need for a legitimate and accessible web presence to build sender trust.
Related resources
12 resources
Related pages
What are common email deliverability issues during new IP and subdomain warmup after ESP migration?
How does email reputation transfer during IP warming with a new ESP, and how to resolve deliverability issues?
What causes emails to go to spam when migrating to a new ESP and warming an IP?
Why are emails from new dedicated IPs and domains landing in spam?
How to diagnose email deliverability drops after migrating to a new ESP?
What are the best practices for migrating to a new ESP while retaining sender reputation?
How to resolve email deliverability issues and IP blocks when migrating to a new ESP?
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