Summary
When active customer emails are suppressed in transactional email tools like SES due to bounces or complaints, manually removing them from the suppression list is a short-term fix, but it's crucial to address the root causes to prevent recurrence and protect sender reputation. Suppressions are typically implemented by email service providers (ESPs) like SES to safeguard your sending reputation by preventing further sends to problematic addresses. Simply un-suppressing without understanding why can lead to increased bounces, complaints, and potential blocklist issues, impacting your overall email deliverability, even for important transactional messages. Understanding the specific reason for suppression, such as hard bounces versus spam complaints, is vital for formulating an appropriate strategy. For instance, an email address that has generated a spam complaint should be handled with extreme caution, often requiring explicit re-opt-in from the customer. Conversely, some transient bounces might resolve themselves.
Key findings
- Suppression purpose: Transactional email tools use suppression lists to protect your sending reputation by preventing further emails to addresses that have bounced or lodged complaints.
- ESPs vs. Mailbox providers: Suppression in tools like SES is distinct from mailbox provider (Google, Yahoo) filters; it is an internal measure by the ESP to manage risk.
- Reason matters: The reason for suppression (bounce, complaint) dictates the appropriate action. Manually removing an address suppressed for a complaint without user re-confirmation is risky.
- Risk of re-engagement: Sending a sudden spike of emails to previously suppressed addresses, especially those that bounced permanently or complained, can negatively impact your sender reputation and lead to new delivery issues. Learn more about managing deliverability when re-engaging inactive subscribers.
- Transactional definitions: If transactional emails are generating complaints, it may indicate they are not truly transactional or are too frequent/noisy, leading recipients to mark them as spam.
Key considerations
- Investigate suppression reasons: Before un-suppressing, obtain detailed reasons for why each address was added to the list, including last delivery date, bounce type, or complaint status. This information is available from your ESP, for example, how SES handles bounce suppression.
- Handle complaints with caution: For addresses suppressed due to spam complaints, avoid automatic re-enabling. Instead, reach out manually or require explicit re-opt-in from the customer to ensure they genuinely want to receive emails, including transactional ones.
- Address hard bounces: For permanent (hard) bounces, un-suppressing will likely result in immediate re-suppression or severe deliverability issues. It's often best to keep these addresses suppressed unless confirmed valid by the recipient. Learn what to do when a user's email hard bounces.
- Implement proactive user re-engagement: If transactional emails are critical, consider in-app banners or help pages prompting users with suppressed emails to update their address or explicitly request re-activation. This shifts the burden of re-engagement to the user.
- Review transactional email content: Ensure your transactional emails are strictly transactional (e.g., receipts, password resets) and don't contain marketing content that might trigger spam complaints. Proactively avoid issues by including a 'sent to wrong address' option.
What email marketers say
Email marketers often face the challenge of distinguishing between various suppression reasons and their impact, especially for active customers. While the goal is to ensure critical transactional emails reach recipients, there's a strong emphasis on not undermining sender reputation by prematurely re-engaging addresses that have signaled disinterest or are no longer valid. The general consensus points towards a cautious, data-driven approach, prioritizing the health of the sending domain over immediate re-engagement without user confirmation.
Key opinions
- Distinguish suppression reasons: Marketers must understand the specific reasons for suppression, such as bounces versus complaints, as this dictates the appropriate re-engagement strategy. Not all suppressions are created equal.
- Complaint sensitivity: Re-enabling addresses suppressed due to complaints is highly risky and generally discouraged without explicit re-confirmation from the customer, as it can severely harm sender reputation. You should always review best practices for unengaged subscribers.
- Bounces are less critical: Transient bounces may resolve, allowing for re-engagement, but permanent bounces will likely recur. The primary concern with bounces is managing volume to prevent reputation damage, rather than direct user intent.
- Customer-driven re-engagement: It is better to have customers actively request to be re-enabled (e.g., through an in-app prompt) rather than unilaterally removing them from a suppression list.
- True transactional mail: Marketers should ensure that emails sent from transactional domains are strictly transactional to minimize complaints, which can jeopardize critical communications. Learn about the difference between transactional and marketing emails.
Key considerations
- Review complaint rates: If transactional emails are generating complaints, it's a 'canary in the coal mine' that indicates a potential larger issue with content, frequency, or user expectations that needs immediate investigation.
- Segment suppression lists: Consider maintaining different policies for addresses suppressed due to bounces versus those suppressed due to complaints.
- Implement self-service options: Offer clear pathways for customers to update their email addresses or re-subscribe if they believe they are missing important transactional communications. This can be through in-app notifications or a dedicated help page.
- Audit transactional content: Regularly audit your transactional emails to ensure they only contain necessary information and are not perceived as marketing messages. This can prevent unnecessary spam complaints.
- Prioritize deliverability: The long-term health of your sending reputation (and thus, deliverability of all emails) is more important than individually forcing emails to potentially unwilling or invalid recipients. Read more about troubleshooting transactional emails going to spam.
Marketer view
Email marketer from Email Geeks explains that you should have comprehensive details about why addresses were suppressed, including the last delivery date, bounce status, or complaint reason. Breaking these down into groups, such as bounces versus complaints, allows for different policies to be applied, ensuring more nuanced handling.
Marketer view
Email marketer from Campaign Refinery emphasizes that implementing real-time suppression processing is crucial to immediately honor unsubscribe requests and prevent sending to new complainers. They suggest using separate suppression lists for different campaign types to maintain better control and segment your audience effectively.
What the experts say
Experts strongly advise a cautious and data-driven approach when dealing with suppressed active customer emails. They emphasize that an ESP's suppression list is primarily a protective measure for your sender reputation, not directly tied to mailbox provider filtering. The key is to understand the underlying cause of suppression, especially distinguishing between bounces and complaints, as these warrant vastly different re-engagement strategies. Unilaterally removing an address from a suppression list, particularly after a complaint, can backfire by generating more complaints or hard bounces, thus hurting your overall sender reputation. Instead, experts advocate for user-initiated re-engagement processes and a strict adherence to what constitutes a 'transactional' email to prevent future suppression.
Key opinions
- SES suppression is internal: An expert from Email Geeks clarifies that SES suppression lists primarily manage sending to protect the sender's reputation and are not directly related to mailbox provider filters like Google or Yahoo. This means un-suppressing only affects SES's internal sending rules.
- Complaints are serious: An email expert from Word to the Wise suggests being extremely wary of removing someone suppressed due to complaints. This action should only be considered after manually reaching out to the customer or requiring them to explicitly re-opt in, as complaints significantly impact sender reputation and can lead to being listed on a blocklist or blacklist. Find out what happens when your domain is on a blocklist.
- Bounces and re-suppression: An email expert from Spam Resource notes that if bounces were transient, un-suppressing might lead to delivery, but permanent bounces will simply be suppressed again. This highlights that re-engaging hard bounces is often futile and risky.
- Customer intent is key: Experts advocate for users to explicitly signal their desire to receive emails again. This could involve updating their email, confirming their address, or interacting with a help article. This approach respects user preferences and improves deliverability.
- Not always unfortunate: An expert from Email Geeks suggests that an email being reported as spam, even a transactional one, isn't always 'unfortunate' from a deliverability perspective. If recipients are marking it as spam, they likely mean all mail from that sender, including transactional messages. This points to a potential issue with message clarity or relevance, or that the transactional email wasn't perceived as such.
Key considerations
- Analyze complaint rates: If active customer emails are suppressed due to complaints, it's a significant indicator that your transactional emails may not be perceived as such by recipients, or they are too frequent. This 'canary in the coal mine' situation demands a thorough review of your transactional email strategy. Learn why your emails might be failing.
- Respect user preference: Even for transactional emails, if a user has complained or hard-bounced, it's often best to keep the suppression in place unless the address owner explicitly requests to receive more mail. Forcing emails can damage sender reputation.
- Provide clear re-engagement paths: Instead of manual un-suppression, experts recommend creating a clear help page or in-app banner for users who are not receiving emails. This allows them to update their email or request re-activation, ensuring their consent.
- Legal and compliance: In sensitive sectors like healthcare or banking, there are often legal implications related to sending information to the wrong person. This makes cautious re-engagement (e.g., postal letters, in-office confirmation) even more critical.
- Review email classification: Ensure your emails are genuinely transactional. If they contain marketing elements, they are more likely to generate complaints, even if legally permitted, and could lead to suppression issues. Understand if suppression lists prevent transactional emails.
Expert view
Email expert from Email Geeks indicates that SES's suppression lists are specifically designed to prevent future problems when mailing to certain addresses, rather than being directly influenced by the recipient's mail filtering systems. This implies that managing suppression within SES is primarily about maintaining your standing with Amazon, not directly with the inbox provider.
Expert view
Email expert from Word to the Wise warns against automatically removing someone from a suppression list if they were added due to complaints. Such action should be taken with extreme caution, ideally after manual contact or requiring the customer to explicitly opt in again, to avoid further damage to sender reputation.
What the documentation says
Official documentation from email service providers and industry bodies consistently highlights that suppression lists are a key mechanism for maintaining sender reputation and compliance. They generally operate by automatically adding email addresses that result in hard bounces or spam complaints, preventing further sends to avoid damaging the sender's IP and domain health. While documentation often provides methods for manual removal, it implicitly or explicitly warns about the risks associated with re-engaging problematic addresses without addressing the root cause. The emphasis is on understanding why an address was suppressed and adhering to best practices, particularly for transactional emails, which are often exempt from general marketing suppression rules but can still be blocked due to poor sending hygiene or user complaints.
Key findings
- Automated suppression: Transactional email tools like SES automatically suppress email addresses due to various events, including bounces (hard and soft) and complaints, to protect the sender's reputation.
- Reputation preservation: The primary goal of a suppression list is to prevent further sends to problematic addresses, thereby preserving the sender's deliverability and avoiding blocklistings. Find out why your emails are going to spam.
- Transactional email exceptions: Some documentation indicates that suppressed profiles might still receive transactional emails, but this depends on the specific suppression reason (e.g., permanent bounce vs. unsubscribe). For example, Klaviyo explains transactional email suppression.
- Distinction from marketing: Transactional emails are typically defined as automated, one-to-one communications triggered by a user action, distinctly separate from marketing campaigns. This distinction often influences how suppression lists are applied.
Key considerations
- Audit suppression sources: Routinely check your ESP's suppression lists and understand the specific triggers (e.g., hard bounce, soft bounce threshold, complaint) for each entry. This granular data is critical for informed decisions.
- Re-engagement protocols: While manual removal is possible, documentation often implies or explicitly suggests that re-engaging suppressed addresses, especially those with complaints or persistent bounces, should follow strict re-opt-in protocols to avoid further deliverability issues.
- Separate sending practices: Maintain clear segregation between transactional and marketing email streams and ensure that transactional emails adhere to their strict definition to minimize the risk of complaints. This might involve using different subdomains.
- Monitor deliverability metrics: Actively monitor your bounce and complaint rates for transactional emails. High rates, even on transactional streams, signal underlying issues that could lead to broader deliverability problems. Learn more about why emails are not delivered through Amazon SES.
Technical article
Documentation from Amazon Web Services (AWS) explains how to lift a permanent bounce suppression in SES. It advises checking if the address is on your account's suppression list and removing it if necessary, then attempting to send a new email to see if delivery is successful.
Technical article
Documentation from Klaviyo Help Center clarifies that suppressed profiles generally still receive transactional emails, with the only exceptions being if the suppression reason was specific, such as an email address bouncing permanently or a direct unsubscribe. This highlights the nuance in how suppression lists interact with different email types.
Related resources
10 resources
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