Why are important product emails going to spam and how can I fix it?
Michael Ko
Co-founder & CEO, Suped
Published 4 Jul 2025
Updated 19 Aug 2025
7 min read
It is incredibly frustrating when vital product emails, like purchase confirmations, account notifications, or event tickets, end up in recipients' spam or junk folders. These are not marketing messages, but essential communications that customers expect and need to receive. When they fail to land in the inbox, it can severely impact user experience, lead to support tickets, and erode trust in your brand.
Many factors can contribute to this problem, from technical misconfigurations to content issues or rapid changes in sending volume. The good news is that most of these issues are identifiable and fixable with the right approach. Understanding the root causes is the first step toward ensuring your important messages reach their intended destination.
This guide will explore common reasons why product emails might be misclassified as spam and provide actionable steps to diagnose and resolve these deliverability challenges. I will focus on practical solutions to improve your email sending reputation and ensure crucial communications always hit the inbox.
Diagnosing common causes of deliverability issues
When your product emails start landing in the spam folder, it's natural to suspect issues with your sending IP address. While IP reputation plays a role, for major inbox providers like Gmail, your domain's reputation is often a more significant factor. This is particularly true if you are sending crucial emails to recipients who may not have actively engaged with your brand or opted in directly, such as when someone else purchases a ticket or service on their behalf. The lack of prior engagement from the recipient's side can make these emails appear unsolicited, triggering stricter spam filters.
Another common pitfall is rapid volume scaling. If your email volume suddenly jumps from a few hundred emails a day to thousands, especially on a new or less established sending domain, mailbox providers may view this as suspicious. They implement volume limits to prevent spammers from exploiting the system. While 10,000 emails a day might seem substantial, it is still considered a relatively low volume by major providers. However, a sudden spike without proper domain warm-up can still raise red flags. This challenge is magnified if you're effectively acting as an Email Service Provider (ESP), sending on behalf of other parties or managing a high volume of unengaged recipients, which requires a more robust deliverability strategy.
Even plain text emails can encounter deliverability issues if they lack sufficient engaging content or include elements that trigger spam filters. While simple content can be effective for product-related messages, it is important to balance simplicity with indicators of legitimacy and value. This means ensuring your content avoids common spam triggers and aligns with recipient expectations. Furthermore, the format of attachments, such as tickets delivered as .pdf files, can sometimes be an issue for certain mailbox providers, making it preferable to send links instead.
Technical and infrastructure best practices
Email authentication is the bedrock of good deliverability. If your SPF, DKIM, and DMARC records are not correctly set up, your emails are far more likely to be flagged as spam. These protocols verify that your emails are legitimately sent from your domain, preventing spoofing and improving your sender reputation. A simple guide to DMARC, SPF, and DKIM can help you understand the basics.
It is best practice to separate your transactional emails from your marketing or bulk sends. This means using different IP addresses (or subdomains with different IP pools) for each category. Transactional emails, like order confirmations or password resets, typically have high engagement and are expected by recipients, giving them a higher deliverability priority. Marketing emails, on the other hand, might experience fluctuating engagement rates and can impact the reputation of the IP they are sent from. By segregating these flows, you protect the critical path of your product emails from being affected by the performance of your marketing campaigns. If your transactional emails are going to spam, this separation is a crucial first step.
Beyond authentication, ensuring your sending IP has a properly configured PTR (Pointer) record that matches your sending domain is important. While less critical than SPF, DKIM, and DMARC for some providers, a missing or misconfigured PTR record can still contribute to emails being flagged, especially by older or stricter spam filters. It is a fundamental part of the email sending infrastructure that verifies the sender's identity in reverse.
Engagement: High, as recipients typically initiate the action triggering the email.
Sending IP: Use a dedicated or highly reputable IP to maintain consistent deliverability.
Volume: Can vary but should be consistent with user actions.
Content and engagement
The content of your product emails, even if plain text, should be carefully reviewed. While attachments like PDFs are often convenient for tickets, they can sometimes trigger spam filters. Consider sending a link to a secure download or a web-based version of the ticket instead. Furthermore, ensure the subject line is clear, concise, and immediately conveys the email's purpose. Avoid overly promotional language or spam trigger words, even in transactional emails. For more in-depth advice on content, Postmark's guide on why emails go to spam offers valuable insights.
Recipient engagement is a major factor for mailbox providers. If recipients aren't opening, clicking, or marking your emails as not spam, your sender reputation can suffer. This is particularly challenging when someone else buys a product or ticket for the email recipient, meaning the recipient might not recognize your brand. To combat this, consider: asking the purchaser to inform the recipient to look out for the email, sending a follow-up email to the purchaser asking them to confirm receipt, or providing clear instructions on how to whitelist your email address. Building initial recognition is key.
List validation and throttling
Even if you believe your lists are clean, basic email list validation before sending, especially for high-volume or new recipient lists, can significantly reduce bounces and spam trap hits. Sending to invalid or unengaged addresses harms your sender reputation and can lead to blacklisting (or blocklisting) (e.g., being placed on a blacklist). If you are sending batch emails, implementing throttling, which means gradually increasing your sending volume, can help warm up your domain and IP, preventing sudden spikes that might trigger spam filters. This is particularly relevant when moving from low season to high season volume.
To accurately diagnose deliverability problems, you need data. Google Postmaster Tools is an invaluable, free resource that provides insights into your sending reputation, spam rates, and authentication errors, particularly for Gmail recipients. If your volume is high enough, it will populate with critical data that can guide your remediation efforts. Similarly, other major providers like Microsoft and Yahoo also offer their own postmaster tools or deliverability guidelines.
Regularly checking if your domain or IP address is listed on any email blacklists (also called blocklists) is essential. While private blocklists used by individual mailbox providers are often more impactful, public blacklists can also indicate a severe reputation problem. A listing on a major blacklist can lead to widespread deliverability issues. Understanding what an email blocklist is and how it works is important for proactive monitoring. If you find yourself on a blocklist, follow the delisting procedures carefully and address the underlying cause of the listing to prevent recurrence.
A comprehensive approach to deliverability means constant vigilance. This includes not only technical checks but also continuous monitoring of your engagement metrics (opens, clicks, complaints) and adapting your sending practices as needed. If your emails are going to spam, analyzing the full email journey, from content to recipient interaction, is vital.
Views from the trenches
Best practices
Maintain strong email authentication (SPF, DKIM, DMARC) for all sending domains.
Segment email streams, using separate IPs/subdomains for transactional vs. marketing emails.
Regularly monitor your domain and IP reputation using postmaster tools.
Prioritize sending links over attachments where possible, especially for tickets or documents.
Common pitfalls
Ignoring domain reputation and focusing solely on IP reputation.
Rapidly increasing email sending volume without proper warm-up procedures.
Sending emails to unvalidated or unengaged lists, leading to spam traps.
Using generic plain text content that doesn't encourage recipient engagement.
Expert tips
Implement email list validation for all new recipient lists, even if seemingly clean.
Set up a DMARC policy with reporting to gain visibility into authentication failures and potential abuse.
For transactional emails, consider marking them up as such to aid inbox providers.
If recipients are not recognizing your brand, explore pre-delivery messaging through the purchaser.
Marketer view
Marketer from Email Geeks says that typically, the domain is much more important in determining email placement than the IP addresses, with only a few exceptions.
2020-01-13 - Email Geeks
Marketer view
Marketer from Email Geeks says that Gmail does not care as much about the IP as it does about the domain reputation, and that plain text content might be an issue if there is not enough to engage with.
2020-01-13 - Email Geeks
Achieving consistent inbox placement
Ensuring your important product emails reach the inbox requires a comprehensive and proactive approach to email deliverability. It is rarely a single issue, but rather a combination of technical configurations, content quality, sending volume management, and recipient engagement that determines success.
By focusing on strong authentication, segmenting your email streams, optimizing your content, validating your lists, and continuously monitoring your performance through tools like Google Postmaster Tools, you can significantly improve your inbox placement. The journey to flawless deliverability is ongoing, but with consistent effort, your critical product emails will consistently land where they belong: in your customers' inboxes, not their spam folders.
Gmail, your domain's reputation is often a more significant factor. This is particularly true if you are sending crucial emails to recipients who may not have actively engaged with your brand or opted in directly, such as when someone else purchases a ticket or service on their behalf. The lack of prior engagement from the recipient's side can make these emails appear unsolicited, triggering stricter spam filters.
Microsoft and 
Yahoo also offer their own postmaster tools or deliverability guidelines.
