Why has Gmail deliverability dropped recently and emails are going to spam?
Matthew Whittaker
Co-founder & CTO, Suped
Published 18 May 2025
Updated 18 Aug 2025
7 min read
It’s a frustrating scenario: your emails, once reliably landing in Gmail inboxes, are now veering off into the spam folder. This drop in deliverability can significantly impact your communication, sales, and overall email marketing efforts.
Many senders have noticed a shift recently, and it's not always clear why. While the core principles of good email sending remain, major mailbox providers like Google (Gmail) have been refining their spam filtering algorithms and implementing stricter requirements, especially for bulk senders. Understanding these evolving standards is crucial to ensuring your messages reach their intended recipients.
Understanding recent changes and sender requirements
Gmail, alongside Yahoo, introduced significant new sender requirements for bulk senders (those sending over 5,000 emails per day to Gmail addresses) that came into effect in early 2024. These changes are designed to improve security and reduce spam for their users. If your sending practices don't align with these updated guidelines, your deliverability to Gmail can drop dramatically, leading to emails going to spam or being outright rejected.
The primary pillars of these new requirements include robust email authentication, a very low spam complaint rate, and easy one-click unsubscribe options. Failing on any of these fronts can immediately signal to Gmail that your emails are not trustworthy, regardless of your past sending history. It's no longer enough to just “hope” your emails get through, active compliance is a must.
For instance, robust email authentication means properly configuring SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance). These protocols verify that you are who you say you are and that your emails haven't been tampered with in transit. Without these in place, or with misconfigurations, Gmail's filters are highly likely to flag your messages as suspicious or spam. For more specific information, refer to Google’s email sender guidelines.
You can learn more about how to fix common DMARC issues. Proactively addressing these technical aspects is fundamental to maintaining a positive sender standing.
The critical role of sender reputation
Good sending practices
Consistent sending volume: Maintain a steady email sending volume rather than sending large, infrequent bursts.
High engagement: Focus on sending relevant content that encourages opens, clicks, and replies.
Low complaint rates: Keep spam complaints to an absolute minimum, ideally below 0.1%.
Clean lists: Regularly remove inactive or unengaged subscribers.
Poor sending practices
Spiky sending volume: Sending huge volumes after periods of inactivity can appear suspicious.
Low engagement: Sending to unengaged subscribers can harm your sender reputation.
High complaint rates: Too many users marking your emails as spam will quickly lead to blocklists.
Outdated lists: Sending to old or purchased lists increases bounce and spam trap hits.
Your sender reputation, encompassing both your sending IP address and domain reputation, is paramount to Gmail deliverability. Gmail tracks how recipients interact with your emails, and this behavior directly influences your reputation score. A poor reputation signals to Gmail that your emails are unwelcome, resulting in them being sent to the spam folder, or even blocked entirely.
Key factors influencing your sender reputation include low engagement rates, a high volume of emails marked as spam by recipients, and excessive bounce rates. Gmail recommends maintaining a spam rate of below 0.1%, with a maximum tolerance of 0.3%. You can find more details on these thresholds and the 2024 changes in this guide to 2024 email deliverability updates. Exceeding this tiny threshold can trigger severe deliverability issues, indicating that your audience either doesn't want your emails or finds them irrelevant.
Maintaining a good reputation requires consistent monitoring and proactive list management. If you notice a sudden increase in Gmail spam filtering, it often points back to a shift in these engagement metrics or an issue with your sending practices. Addressing these foundational elements is crucial for long-term inbox placement.
Content quality and list hygiene
The danger of unengaged subscribers
Impact on deliverability: Gmail prioritizes user engagement. Sending to a high proportion of users who don't open or click your emails tells Gmail your content isn't wanted, leading to spam folder placement for all your emails, even those sent to active users.
Inactive account deletion: Google has announced policies to delete inactive accounts. Sending to these addresses will result in bounces and further harm your sender reputation.
The content of your emails also plays a significant role in how Gmail's filters perceive them. While not the sole factor, certain content characteristics can contribute to emails being flagged as spam. This includes using excessive capitalization, too many exclamation marks, generic or misleading subject lines, or containing broken links. Ensure your email design is clean and professional, avoiding elements that are commonly associated with spam.
Beyond content, the health of your email list is a critical deliverability factor. Sending to inactive or invalid email addresses can lead to high bounce rates and even hit spam traps, which are designed to catch senders with poor list hygiene. Regularly cleaning your email list to remove unengaged subscribers or those with invalid addresses is a best practice that improves your overall sender reputation and reduces the likelihood of landing in the spam folder.
An unengaged subscriber who consistently ignores your emails can negatively impact your sender reputation, as Gmail interprets this as a lack of interest in your content. This can lead to your emails being placed in the spam folder for even engaged users. Make sure you avoid common pitfalls that cause emails to go to spam.
Technical configurations and blocklists
Example DMARC record (TXT record)DNS
_dmarc.yourdomain.com IN TXT "v=DMARC1; p=none; rua=mailto:reports@yourdomain.com; ruf=mailto:forensics@yourdomain.com; fo=1;"
Proper technical setup is the backbone of good email deliverability. This includes ensuring your DNS records for SPF, DKIM, and DMARC are correctly configured and remain valid. Errors in these configurations can prevent your emails from authenticating properly, making them prime targets for Gmail's spam filters. A DMARC record, for instance, allows you to tell receiving mail servers how to handle emails that fail SPF or DKIM authentication for your domain.
Your sending IP address or domain might also end up on an email blacklist (or blocklist). These lists are maintained by various organizations and track IPs or domains known for sending spam. If you find your domain on a blacklist, it's a major red flag for Gmail, almost guaranteeing your emails will go to spam. Regularly checking your blocklist status is an essential part of proactive email deliverability management.
Regularly clean your email lists of unengaged subscribers to improve overall deliverability and sender reputation.
Carefully monitor bounce messages for specific error codes and URLs provided by Gmail for troubleshooting.
Implement and continually verify all email authentication protocols: SPF, DKIM, and DMARC.
Adapt to evolving spam filter rigidity by staying informed about industry changes and provider requirements.
Common pitfalls
Relying solely on inflated open rates (e.g., due to MPP) as a true measure of engagement.
Failing to address bounce messages, which often contain critical information about delivery issues.
Not understanding the full impact of sending to inactive or unengaged email accounts.
Neglecting to monitor your domain and IP reputation, leading to undetected deliverability problems.
Expert tips
Consider hiring a deliverability consultant if you're struggling to diagnose complex email delivery issues.
Recognize that the "cat and mouse game" with spam filters is ongoing, requiring continuous adaptation.
Prioritize verifiable engagement metrics over potentially inflated ones when assessing list health.
Proactively cut back on sending to subscribers who have recently opened but haven't clicked to improve engagement signals.
Marketer view
Marketer from Email Geeks says: My team has noticed Gmail getting more rigid with spam filters lately, and we're constantly adapting to changes in their algorithm, which sometimes causes collateral damage.
2023-05-20 - Email Geeks
Marketer view
Marketer from Email Geeks says: We've started to cut back on recent openers who haven't clicked in a while to address issues, as we believe Gmail is cracking down on senders who concentrate on openers not genuinely engaging.
2023-05-23 - Email Geeks
Navigating Gmail's evolving landscape
The recent shifts in Gmail's deliverability, leading to more emails landing in spam, are a clear signal of their commitment to a cleaner inbox experience for users. For senders, this means a heightened focus on email authentication, maintaining an impeccable sender reputation, ensuring genuine subscriber engagement, and rigorous list hygiene. It's a dynamic environment, but by prioritizing these core principles, you can significantly improve your chances of consistently reaching the inbox.
(Gmail) have been refining their spam filtering algorithms and implementing stricter requirements, especially for bulk senders. Understanding these evolving standards is crucial to ensuring your messages reach their intended recipients.
Yahoo, introduced significant new sender requirements for bulk senders (those sending over 5,000 emails per day to Gmail addresses) that came into effect in early 2024. These changes are designed to improve security and reduce spam for their users. If your sending practices don't align with these updated guidelines, your deliverability to Gmail can drop dramatically, leading to emails going to spam or being outright rejected.
