Why are my emails going to spam even with a low spam rate?

Key findings

• Lagged reporting: Spam rate data, particularly from tools like Google Postmaster Tools, can reflect complaints from emails sent days prior, leading to spikes on days with zero sending volume.
• Engagement shifts: Changes in user behavior, such as increased scrutiny of inboxes (e.g., during periods of working from home), can lead to higher unsubscribe or complaint rates, even if email content or volume hasn't changed. This can indicate a disconnect between what users want and what they receive, affecting your sender reputation despite low reported spam rates.
• Contextual filtering: Mailbox providers employ sophisticated filtering algorithms that consider a wide array of signals beyond just explicit spam complaints. These can include engagement metrics (opens, clicks), negative actions (deletes without opening, moving to junk), and historical sender reputation, which might not be immediately reflected in a simple spam rate percentage.
• Relative impact: A small number of complaints can translate into a high spam rate percentage if the sending volume for that specific day is very low. For instance, four complaints on a day with 142,314 emails is low, but if no emails were sent that day, the complaints apply to previous volume, potentially inflating the apparent rate for that specific data point.
• Underlying issues: Issues with content, list quality, or even a sudden change in email cadence can trigger filtering, even if the overall reported spam rate remains low. This means a low rate does not necessarily equate to perfect inbox placement.

Key considerations

• Analyze recent sends: Look at the campaigns sent immediately before the observed spam spike. Evaluate their content, audience, and overall engagement metrics for any anomalies.
• Monitor hidden signals: Focus on metrics beyond just spam rates, such as open rates, click-through rates, and unsubscribe rates, as these provide a more holistic view of recipient engagement and overall email deliverability. Poor engagement often signals unwanted mail and can be a strong factor in emails going to spam (even if not explicitly reported as such). Learn how to determine if marketing emails are going to spam.
• Understand spam rate thresholds: Different email service providers (ESPs) have varying spam rate thresholds, which are the maximum rates they will accept before rejecting or marking your emails as spam. Understanding these thresholds can help contextualize your reported rates.
• Review email authentication: Ensure your SPF, DKIM, and DMARC records are correctly configured. Authentication failures can significantly impact deliverability, regardless of content or perceived spam rate. Explore a simple guide to DMARC, SPF, and DKIM.
• Consider audience behavior: Acknowledge external factors affecting how your audience interacts with emails. Changes in daily routines can influence engagement patterns, leading to different inbox cleaning habits.

Key opinions

• Discrepancy in reporting: Marketers frequently express confusion when postmaster tools show a spam spike on a day with no emails sent, indicating a potential lag in reporting or attribution to previous campaigns.
• Unsubscribe rates as indicators: A higher-than-usual unsubscribe rate (e.g., 70 unsubscribes compared to a typical 10 for a 142k send) is considered a potential precursor or parallel indicator to increased spam filtering.
• Impact of user behavior: There's a prevailing theory that external circumstances, such as people spending more time at home, lead to increased inbox scrutiny and a higher likelihood of users cleaning up their inboxes, resulting in more unsubscribes or complaints.
• Engagement vs. sales: Some marketers observe high open and click rates without corresponding sales, which, while not leading to spam reports, suggests that the content or offer may still have missed the mark with the audience.
• Content and IP reputation: Marketers are aware that poor subject lines, problematic keywords, or a compromised IP address can push emails to spam, irrespective of explicit spam complaint rates. For broader guidance, consider how to prevent your emails from going to spam.

Key considerations

• Review recent campaigns: Always look at what was sent immediately before a deliverability dip, as the content or audience targeted might be the root cause.
• Holistic engagement analysis: Don't just rely on spam rates. Analyze unsubscribe rates, open rates, and click rates together. A low spam rate might hide other issues, especially regarding how high sending frequency affects deliverability.
• Acknowledge user context: Consider how external events or changes in daily routines might impact how subscribers interact with emails. This can explain shifts in engagement or complaint behavior.
• Content optimization: Continuously optimize subject lines and email content to ensure relevance and engagement, as these are critical for avoiding spam filters and improving overall domain reputation. For insights into this, see a practical guide to understanding your email domain reputation.

Key opinions

• Zero volume spikes: Experts agree that a spam rate spike on a day with zero sending volume is likely due to complaints from previous days' mailings catching up in the reporting. These short-term spikes usually do not have a lasting negative impact on long-term sender reputation.
• Behavioral shifts: There's a consensus that people spending more time at home might be more inclined to scrutinize their inboxes, leading to higher rates of unsubscribing or filing complaints. This triaging behavior can affect deliverability metrics even without changes from the sender's end.
• Content relevance: The content sent immediately before a spam rate increase is critical. If engagement (like opens) remains steady but clicks or opt-outs drop, it suggests recipients are not finding the call to action or overall content engaging, potentially leading to filtering.
• Hidden filtering: Even with a low reported spam rate, emails can be silently filtered to spam or other tabs by Gmail or other ISPs based on complex algorithms that consider individual engagement signals beyond direct complaints. This means you need to consider understanding Google Postmaster Tools V2 spam rate dashboard fully.
• Sender reputation complexity: Sender reputation is multifaceted, influenced by bounce rates, complaint feedback loops, and consistent audience engagement. These factors provide early warnings about list quality or content problems, which can disproportionately affect deliverability, even if explicit spam flags are low. Sometimes emails just go missing or get silently dropped.

Key considerations

• Proactive list hygiene: Maintaining a clean and engaged email list is paramount. Even if spam rates are low, high unsubscribe rates or low engagement signal underlying list quality issues that will eventually impact deliverability.
• Deeper metric analysis: Look beyond surface-level spam rates. Analyze granular engagement data, including opens, clicks, and especially negative signals like deletes without opening, to catch subtle deliverability shifts. These insights are key to understanding why your emails are going to spam.
• Content and CTA optimization: Regularly review and optimize your email content, including subject lines and calls to action. Low click rates despite good opens can indicate a need for more compelling content, which directly impacts recipient satisfaction and long-term deliverability.
• Authentication checks: Ensure all email authentication protocols (SPF, DKIM, DMARC) are correctly implemented and monitored. Authentication failures can block emails outright or route them to spam, regardless of your content or perceived spam rate.

Key findings

• Sender reputation impact: A poor sender reputation is a critical factor leading to emails being placed in the spam folder. This reputation is built over time based on various signals, not just direct spam complaints.
• Spam rate thresholds: ESPs define a maximum spam rate they will tolerate. Exceeding this threshold can result in emails being rejected or automatically marked as spam, even if the overall rate appears minor to the sender.
• Engagement as a signal: Low engagement rates (e.g., opens and clicks) signal to ISPs that an email might be unwanted or irrelevant, significantly increasing its likelihood of being marked as spam. Conversely, positive engagement helps build trust.
• Content and design: Email content and design play a direct role in avoiding spam filters. This includes careful consideration of subject lines, keywords, and overall message structure.
• Continuous vigilance: High deliverability is an ongoing effort that requires constant adaptation to evolving ISP requirements and spam filtering algorithms, rather than a one-time setup. This emphasizes the dynamic nature of email deliverability issues.

Key considerations

• Prioritize sender reputation: Focus on building and maintaining a strong sender reputation, as it's a foundational element for inbox placement. This involves consistent sending practices and positive recipient interactions.
• Adhere to thresholds: Be aware of and strive to stay well below the spam rate thresholds set by major ESPs to avoid deliverability penalties.
• Optimize for engagement: Design emails and create content that encourages positive recipient engagement, as this is a strong signal of desired mail. Learn more about why your emails fail.
• Regular content audits: Periodically audit your email content for elements that might trigger spam filters, such as overly promotional language, suspicious links, or poor formatting.
• Stay informed: Continuously monitor and adapt to updates in ISP filtering practices and email deliverability best practices to ensure long-term inbox placement.