Does mentioning covid-19 in email impact deliverability?
Matthew Whittaker
Co-founder & CTO, Suped
Published 26 Jul 2025
Updated 16 Aug 2025
6 min read
When the COVID-19 pandemic first struck, many businesses and organizations found themselves in uncharted territory, needing to communicate critical information rapidly to their audiences. A question quickly emerged within the email marketing community: would simply mentioning "COVID-19" in an email impact its deliverability and cause it to land in the spam folder?
The short answer is, it did, but mostly during the initial surge. Now, the direct impact of the keyword itself is far less significant. Instead, the focus has shifted to the indirect effects, primarily driven by evolving subscriber sentiment and overall email sending practices.
The initial wave: how ISPs reacted to COVID-19
During the early days of the pandemic, Internet Service Providers (ISPs) faced an unprecedented challenge. There was a massive surge in email volume, including a distressing amount of scams, phishing attempts, and misinformation disguised as legitimate COVID-19 updates. This necessitated a strong response from ISPs.
Some ISPs, particularly in regions heavily targeted by these fraudulent emails, temporarily implemented stricter filtering rules. This meant that certain keywords, including "COVID-19" or "coronavirus," could trigger a higher scrutiny level, potentially leading to emails being quarantined or blocked outright. For instance, some French ISPs were observed to block based on these keywords due to the sheer volume of malicious content.
This was primarily a defensive mechanism to protect inboxes from harm and reduce the overwhelming "noise" in the email channel. It wasn't an arbitrary punishment for using the words, but a reaction to the global crisis and the opportunistic bad actors exploiting it.
Legitimate senders with strong sender reputations and proper email authentication protocols in place (like SPF, DKIM, and DMARC) were generally more resilient. While they might have experienced temporary dips, their established trust helped them navigate these hurdles more effectively compared to senders with weaker reputations.
The pivot in email deliverability during a crisis
Initially, ISPs (Internet Service Providers) implemented stringent filtering for COVID-19 related terms due to a high volume of scams and misinformation. This was a temporary, protective measure to safeguard inboxes.
Today, direct keyword blocking for "COVID-19" is rare for legitimate senders. The challenge now lies more with subscriber fatigue and polarized opinions, which can lead to higher spam complaints and lower engagement rates, impacting sender reputation.
The subtle shift: from technical blocks to human reactions
While direct technical filtering for the word "COVID-19" has largely subsided, its mention can still indirectly affect deliverability, primarily due to shifts in subscriber sentiment and behavior.
COVID-19 became a highly divisive and emotionally charged topic. Emails mentioning it, even from legitimate organizations or government bodies, could provoke strong negative reactions from recipients. This often manifested as increased spam complaints, even from subscribers who had explicitly opted in.
Higher complaint rates significantly hurt sender reputation, far more than specific keywords do today. Mailbox providers interpret high complaints as a sign that your audience does not want your emails. This negative feedback loop can push future emails to the spam folder, even if your content doesn't use what might traditionally be considered spam trigger words. Regularly checking your Google Postmaster Tools to monitor your spam rate is crucial.
This evolving impact highlights that deliverability is less about isolated words and more about overall audience engagement and satisfaction. When recipients react negatively, it can suggest that COVID-19 related emails are causing deliverability issues by hurting your sender reputation.
Strategies for sending sensitive content
When addressing sensitive topics, whether they are health crises, political developments, or social issues, your email strategy must prioritize audience relevance and value. Avoid the urge to send mass emails to your entire list unless the information is truly critical and universally applicable to all recipients.
Audience segmentation is paramount. Only send information about sensitive topics to those who have explicitly opted in for such content or for whom it is directly and unequivocally relevant. This approach significantly reduces the risk of unwanted emails leading to complaints or unsubscribes, as detailed in best practices for sending to unengaged lists during a crisis.
Focus on clarity, empathy, and providing genuine value. Your subject lines should accurately reflect the content and set clear expectations. Vague, sensational, or alarmist language can backfire, increasing negative reactions. For further guidance, Mailgun offers excellent insights on COVID-19 email communications.
Crucially, ensure your overall email program adheres to fundamental deliverability best practices. This includes robust email authentication (SPF, DKIM, DMARC) and consistent list hygiene. You should always check your blocklist status, as being on a blacklist can severely impact your ability to reach the inbox. Adweek also covers common deliverability mistakes to avoid during crises.
Sending during a crisis
Audience segmentation: Target only truly engaged or relevant subscribers with crisis communications.
Clear communication: Provide factual, concise, and helpful information.
Value proposition: Explain why the email is necessary and beneficial to the recipient.
Frequency adjustment: Consider reducing sending frequency to avoid overwhelming subscribers with sensitive topics.
Impact on deliverability
Complaint rates: Expect higher complaints if content is unwanted or perceived as political.
Unsubscribe rates: Increased unsubscribes from fatigued or disengaged recipients.
Engagement metrics: Potential decline in opens and clicks, signaling lack of interest.
Sender reputation: Negative interactions can lead to a damaged sender reputation.
Long-term deliverability lessons
The experience of sending emails during the pandemic reinforced the enduring principles of email deliverability. Mailbox providers prioritize user experience above all else. This means that emails consistently generating complaints or low engagement will suffer, regardless of the specific keywords they contain.
Proactive monitoring of your email program is essential for long-term success. Regularly review your engagement metrics, such as open rates, click-through rates, and spam complaint rates. Additionally, routinely check if your sending domain or IP is on any public email blocklists (or blacklists). These indicators are far more critical than isolated content terms.
Implementing strong email authentication is non-negotiable. A well-configured DMARC, SPF, and DKIM setup is fundamental for proving your emails are legitimate and protecting your domain reputation from spoofing and phishing attempts.
Ultimately, focusing on maintaining a healthy, engaged list, ensuring strong authentication, and providing relevant, valuable content will always be the most effective strategies for maintaining high inbox placement. These principles apply to all email marketing efforts, not just communications during a crisis.
Views from the trenches
Best practices
Segment your email lists to ensure COVID-19 content is sent only to relevant and engaged subscribers.
Prioritize providing clear, concise, and value-driven information in your crisis communications.
Regularly monitor your email engagement metrics, including open rates, click-through rates, and spam complaints.
Maintain strong email authentication protocols like SPF, DKIM, and DMARC for all your sends.
Common pitfalls
Sending mass COVID-19 emails to unengaged or entire lists, risking high complaint rates.
Using alarmist or vague subject lines that do not clearly communicate the email's purpose.
Failing to acknowledge evolving subscriber sentiment and potential fatigue towards crisis-related content.
Neglecting to monitor sender reputation indicators, which are crucial for long-term deliverability.
Expert tips
Understand that while direct keyword filtering for "COVID-19" may have decreased, recipient reaction still heavily influences inbox placement.
Treat sensitive topics with the same strategic planning as highly important marketing campaigns, focusing on audience consent and relevance.
Recognize that even official or necessary communications can face deliverability challenges if they trigger strong negative subscriber responses.
Leverage DMARC reports to identify authentication issues that might be contributing to deliverability problems.
Marketer view
Marketer from Email Geeks says that they have not seen deliverability issues recently related to mentioning COVID-19, provided other email practices are sound and consent is clear.
July 22, 2022 - Email Geeks
Marketer view
Marketer from Email Geeks says that at the beginning of the outbreak, some French ISPs blocked emails with COVID-19 keywords due to a high volume of scams, but this was a temporary measure.
July 22, 2022 - Email Geeks
Key takeaways for email deliverability
While the direct impact of mentioning "COVID-19" in emails on deliverability has largely diminished since the early days of the pandemic, the indirect effects stemming from subscriber perception and reaction remain crucial.
The biggest lesson learned is that user engagement and sentiment are paramount. A strong sender reputation, built on consistent permission-based sending, relevant content, and diligent monitoring, will always be your best defense against deliverability challenges, regardless of the specific topic you are discussing.
