Summary
Diagnosing and resolving email deliverability issues within HubSpot, especially when dealing with a large contact database that includes cold emails, requires a systematic approach. Many organizations, particularly fast-growing software companies, encounter challenges with low inbox placement and high bounce rates due to various factors, including the quality of acquired email addresses and past sending practices. A HubSpot account representative may confirm a dedicated IP isn't the sole solution, highlighting the need for deeper investigation into underlying issues such as list hygiene and audience segmentation. This summary outlines key findings and considerations for tackling these complex deliverability challenges.
Key findings
- Low quality sign-ups: Fast-growing companies often experience deliverability problems stemming from automated bot sign-ups, temporary emails, or paid acquisition quality issues, leading to a high volume of invalid or unengaged contacts in the database.
- Impact of cold email: Sending cold emails, even on a separate subdomain or ESP, can negatively impact the overall domain health and sender reputation, affecting the deliverability of marketing and transactional emails from the main domain or other subdomains. This is a common issue when managing sender reputation after sending cold emails.
- Segmentation challenges: With hundreds of thousands of contacts, effective segmentation becomes challenging, making it difficult to isolate engaged, valid recipients from high-risk or unengaged addresses. This leads to continued high bounce rates even after using email verifiers.
- Insufficient consent: Email verification for product usage does not equate to marketing consent. Sending marketing emails without explicit double opt-in can lead to lower engagement and increased spam complaints, harming deliverability.
Key considerations
- Database cleansing: Prioritize a thorough cleaning of your entire contact database to remove hard bounces, spam traps, and unengaged contacts. Relying solely on email verifiers may not catch all problematic addresses, like temporary or improperly formatted ones.
- Strategic segmentation: Implement a robust segmentation strategy based on engagement levels, historical data, and verification results. This includes categorizing contacts into highly engaged, recently inactive, cold/inactive, and high-risk groups to tailor sending practices appropriately. For more on this, check out cold email deliverability best practices.
- New domain strategy: While a new domain for marketing emails can be beneficial, it should only be considered after addressing the root causes of poor deliverability. Without fixing underlying issues, a new domain will likely face similar problems over time. Consider how to manage email deliverability for large sends carefully.
- Consent management: Re-evaluate consent acquisition practices. Implementing a true double opt-in process for marketing communications, distinct from product verification, is crucial for building a healthy, engaged list. This aligns with modern email deliverability standards discussed by email deliverability rule updates.
What email marketers say
Email marketers often face complex challenges when their HubSpot email deliverability declines, especially with large, historical databases containing cold or unengaged contacts. Their experiences highlight the critical importance of understanding the root causes beyond just technical configurations or the ESP itself. Many emphasize that a new sending domain is not a silver bullet without first addressing the underlying issues of list quality and segmentation. The consensus among marketers points towards a need for aggressive list hygiene and thoughtful audience management to rebuild sender reputation and achieve better inbox placement.
Key opinions
- Root cause focus: Marketers strongly advise against moving to a new domain without first identifying and fixing the fundamental issues contributing to poor deliverability. A cleaned and properly segmented database is seen as the prerequisite for any long-term success, as discussed in troubleshooting general email deliverability issues.
- List hygiene priority: Aggressive list hygiene is paramount, including the immediate removal of hard bounces, spam traps (or blocklist traps), and unengaged contacts. Even with email verifiers, some invalid or temporary addresses can slip through, necessitating continuous monitoring and suppression.
- Cold email impact: The use of the same domain, even with a different subdomain, for cold email campaigns can negatively affect the overall domain health and reputation for marketing emails. It is advisable to stop cold emails on compromised subdomains and reintroduce those leads only after a structured warm-up and careful segmentation.
- Segmentation by engagement: Marketers emphasize segmenting audiences based on their engagement levels, historical behavior, and email verification results. This means prioritizing sends to highly engaged users and gradually re-engaging less active segments, while suppressing high-risk contacts. For more on this, HubSpot themselves provide some useful resources about HubSpot email deliverability best practices.
Key considerations
- Immediate action on cold sends: If cold email campaigns are causing deliverability issues, immediately halt sending from the affected subdomain or domain to prevent further damage to sender reputation. This is critical for improving email deliverability with unengaged lists.
- Segment before warming: For any new domain or re-warming efforts, ensure the audience is meticulously segmented and cleansed before starting. Proper audience segmentation is more effective than just relying on email verification alone, which can miss certain invalid addresses.
- Prioritize engaged segments: Begin sending marketing emails to your most engaged audience segments first. This helps build positive sending history and sender reputation with mailbox providers before expanding to less engaged groups. This is a crucial step for improving SPF alignment and HubSpot deliverability.
- Continuous monitoring: Implement ongoing monitoring of email metrics, including bounce rates, spam complaints, and engagement, to quickly identify and address new issues. Regular list cleaning and re-engagement campaigns are essential for maintaining a healthy sending environment.
Marketer view
A Marketer from Email Geeks indicates that deeper analysis is necessary for severe deliverability problems. They suggest that a new domain alone won't solve underlying issues if the database remains uncleaned and improperly segmented.Prioritizing list hygiene is key before any domain changes, as the root causes of poor deliverability must be addressed first.
Marketer view
An Email Marketer from Email Geeks explains that whenever a fast-growing SaaS company with hundreds of thousands of contacts experiences deliverability issues, it's frequently linked to low-quality sign-ups. This includes automatically generated accounts (bots) or problems with paid acquisition channels leading to invalid or unengaged email addresses, which quickly degrade sender reputation.
What the experts say
Email deliverability experts often highlight that issues with a large database, particularly when cold emails are involved, are rarely simplistic. They emphasize that the specific email service provider (ESP) – even HubSpot – is less critical than understanding the fundamental practices of email acquisition, the nature of the mail being sent, and the specific metrics indicating problems. Experts frequently point out that the terms "cold" and "clean, healthy" are inherently contradictory in the email sending landscape, making it difficult to achieve good deliverability without significant changes to acquisition and sending behaviors. They stress the need for a holistic view rather than focusing on isolated symptoms.
Key opinions
- Holistic diagnosis: Experts stress the need to look at the broader picture, including how addresses are acquired, the type of mail sent, and specific rejection messages. The choice of ESP (like HubSpot) is secondary to these foundational aspects of email program health.
- Cold vs. clean contradiction: A fundamental tension exists between sending "cold" emails and maintaining a "clean, healthy" sending reputation. Experts generally agree that aggressive cold emailing is detrimental to long-term deliverability, making success in this area very challenging.
- Beyond verification: While email address verification is a good step, experts caution that it does not equate to gaining consent for marketing. Proof of email ownership (COI) is distinct from explicit permission to send promotional content, impacting overall deliverability and potential blocklist issues. Learn more about what an email blacklist is.
- Consultant value: Engaging a seasoned deliverability consultant can provide valuable insights and reduce guesswork, helping to pinpoint exact issues and strategize effective remediation. This can be more effective than trying to solve complex deliverability drops in isolation. Consider how email experts troubleshoot deliverability.
Key considerations
- Comprehensive data review: Before seeking external help, gather all relevant data: business type, acquisition methods, mail types, problem metrics, rejection messages, and problematic mailbox providers. This provides a clear picture for a consultant to work with, helping to understand your email domain reputation.
- Acquisition practices: Tighten lead acquisition practices to prevent low-quality sign-ups. This includes implementing stronger anti-bot measures and scrutinizing sources of paid acquisition that might bring in invalid or unengaged contacts.
- Separate sending strategies: If cold emailing is a business necessity, consider a completely separate sending infrastructure and domain from your core marketing and transactional emails to minimize cross-contamination of sender reputation. This is critical as cold email can lead to spam traps.
- Focus on wanted email: The focus should shift towards sending only wanted email. There is no magic solution for delivering unwanted (spam) email reliably to the inbox. Building a consensual, engaged list is the most sustainable path to high deliverability. This requires careful alignment with DMARC, SPF, and DKIM best practices. For a simple guide, see A simple guide to DMARC, SPF, and DKIM.
Expert view
A Deliverability Expert from Email Geeks suggests that to narrow down deliverability problems, it's crucial to understand the business, how addresses are acquired, the type of mail being sent, and specific problem metrics like rejection messages. This information is more important for wooing a consultant and pinpointing the exact issue than simply knowing the Email Service Provider (ESP) being used.
Expert view
An Email Deliverability Consultant from Email Geeks asserts that cold and clean, healthy are contradictory terms in email deliverability. They explain that a truly healthy email infrastructure is built on consent and engagement, which is inherently at odds with unsolicited cold outreach, making sustained success challenging.
What the documentation says
Official documentation and industry standards consistently emphasize that robust email deliverability relies heavily on consent, engagement, and maintaining a clean sending list. For platforms like HubSpot, while the platform provides tools, the ultimate responsibility for list quality and sending practices rests with the sender. Documentation frequently highlights the importance of proper authentication (SPF, DKIM, DMARC), managing bounces and complaints, and adhering to strict anti-spam guidelines. It underscores that any activity perceived as unsolicited, like cold emailing, can significantly degrade sender reputation, regardless of the ESP or the size of the database.
Key findings
- Consent is paramount: Documentation consistently states that explicit consent is the foundation of good deliverability. This goes beyond simple email verification and often recommends double opt-in for marketing lists to ensure active subscriber engagement.
- List hygiene importance: Regular list cleaning is a critical best practice to remove invalid addresses, hard bounces, and unengaged subscribers. Sending to these addresses wastes resources and negatively impacts sender reputation.
- Sender reputation impact: Any sending activity, including cold emails from subdomains, contributes to the overall domain and IP reputation. Poor performance (high bounces, complaints) from one part of the sending infrastructure can affect others. Learn more about how to cold email correctly.
- Authentication standards: Proper configuration of email authentication protocols like SPF, DKIM, and DMARC is essential for proving sender legitimacy and preventing spoofing. Failures in these areas can lead to emails being marked as spam. For more technical details, see technical solutions for email deliverability.
Key considerations
- Implement strong opt-in: Review and strengthen your opt-in processes. If possible, transition to a double opt-in for marketing communications. This ensures a more engaged and higher-quality list from the start.
- Monitor deliverability metrics: Regularly monitor key deliverability metrics within HubSpot (or a third-party tool) such as bounce rates (hard and soft), spam complaint rates, and open/click rates. These provide early warnings of issues. Understanding why emails go to spam is crucial.
- Segment based on engagement: Segment your database not just by customer type, but by engagement levels. This allows for targeted sends that protect your reputation by limiting volume to less engaged or higher-risk segments.
- Dedicated sending strategy: If cold outreach remains a strategy, consider using a distinct domain and IP address, completely separate from your main marketing and transactional emails, and apply stringent list validation and warm-up processes specific to that use case.
Technical article
Official HubSpot documentation often explains that while HubSpot helps with email sending, ultimately the sender's practices determine deliverability. It clarifies that simply using HubSpot doesn't guarantee inbox placement without adherence to best practices. It emphasizes that maintaining high email deliverability relies heavily on sending relevant content to engaged subscribers who have explicitly opted in, minimizing complaints and bounces, which are key indicators for mailbox providers.
Technical article
A guide on email marketing best practices typically states that a clean email list is fundamental to achieving and sustaining high deliverability. This means active management to ensure the quality of contacts receiving your emails. It further elaborates that regularly removing invalid or inactive email addresses is crucial, as sending to a stale or unengaged list can significantly damage sender reputation and lead to undesirable blocklisting or filtering into spam folders.
Related resources
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