How to Stop Spam Emails in the Era of AI

Spam remained a problem since the inception of email but the current threat landscape with AI assistance has changed significantly that nuisance. To effectively address how to stop spam emails, it is crucial to understand the evolving tactics used by spammers. By April 2025, 51% of spam was driven by AI software, topping the levels of human produced junk in our inboxes. One further concern: generative AI tools allowed bad actors to generate phishing emails 40% faster than before, and more than 82.6% of all phishing campaigns incorporated AI components.

This fast pace change means phishing attacks appear with preciseness, convincing language, and speed, sometimes able to bypass legacy filters relying on sloppy grammatical mistakes or glaring social engineering elements. There are multiple strategies that can stop this new growth of spam and this blog will cover effective strategies on how to stop spam emails.

Why Conventional Email Spam Filters Fall Short in the Context of “How-To-Stop-Spam-Emails”

Traditional approach to filtering out spam such as using signature blacklists, basic rule sets, and heuristic analysis – are getting uncomfortably obsolete:

• Bayesian spam filters, which were used to filter spam, misclassify up to 73.7 % of LLM‑modified spam as legitimate.

• Image-based spam, such as callback phishing, is completely evasive to OCR scanners and would avoid rule proxies hiding behind pictures, rather than text.

• Sophisticated emails that bypass authentication checks would not be picked up from spam filters

Organizations must develop advanced, multilayered defense strategies that keep pace with rapidly evolving attackers as AI-driven competition intensifies.

Key Mitigation Techniques to Block Spam

Here are the top 10 mitigation techniques to help block out spam:

1. Implement Email Authentication (SPF, DKIM, DMARC)
   • Start with the robust set up of SPF, DKIM, and DMARC. Email authentication validates user domains and will dramatically reduce spoofing, which is a critical component before petal out any layer of protection. AI Driven Email Security deploy
2. Utilize advanced filters that leverage threat intel, LLM analysis and vision models:
   • Mesa Security leverages generative AI and multi-modal detection to identify image based callback phishing, BEC, compromised-account scams, spam, and malware.
   • Mesa’s Email Security API integrates with SIEM/SOAR workflows like Splunk and Office 365, enabling real-time auto-quarantine, account reset, and threat blocking.
3. Stack filters and feedback
   • Combine cloud-based gateways with device-based scanning and user feedback mechanisms. Apache SpamAssassin, for example, remains a valuable tool for pattern detection and Bayesian scoring when recently updated. Feedback loops like user spam reports help train filters to adapt to new threats.

How to Protect on Google or Microsoft

Being proactive on how to stop spam emails can greatly enhance your email security. For Google Workspace users that want to put a stop to unwanted emails in gmail, here are the steps that you can take to protect against spam emails:

1. Activate SPF, DKIM & DMARC via the Admin Console.
2. Set Gmail advanced phishing and malware protection, enabling link scanning and attachment sandboxing
3. Deploy Mesa Security with your Google Workspace tenant to scan every inbound message using the latest AI detection
4. Enable auto-remediation by blocking senders if a suspected spam or phishing message was detected.

For users on Office 365, understanding how to stop spam emails starts with effective email authentication methods. Here are the steps that can be leveraged for your Microsoft tenant on how to stop spam emails:

1. Turn on Microsoft Defender for Office 365: activate Safe Attachments and Safe Links
2. Activate SPF, DKIM & DMARC, and anti-spoof protection in Microsoft Defender Security Policies
3. Integrate Mesa Security as it can add extra detection for subtle signals that bypass traditional filters and sophisticated spam that involve images and other more complex signals.
4. Automate response actions such as Mesa being able to mark spam messages, auto-quarantine emails, block spam senders, and feed intelligence back to your SIEM or SOAR via API integration.

The Importance of Leveraging an AI-Native Platform

Mesa utilizes its multi-modal LLM detection paired with custom threat intelligence to accurately detect sophisticated threats where others fail such as image callback phishing, scams from LLMs, BEC, and compromised accounts. In the context of spam, many more sophisticated spam emails are now bypassing your traditional email filters and Mesa delivers the most accurate detection that can layer on top of your traditional defenses and additionally: allows you to block emails categorized as spam.

Mesa also seamlessly integrates with Google Workspace and Office 365 as well as offer an API that plugs right into your SIEM and SOAR. You can easily deploy Mesa in your tenant in less than an hour and the spam monitoring is completely free to test drive! You can choose to monitor all your users or simply a subset of users to understand the velocity of spam targeting your organization.

4 Key Takeaways

Spam is evolving now that over 50% of spam is now AI driven, with phishing attacks rising thousands of percent. Legacy email filters are ineffective: tools that are now signature-based will miss the next generation of threats that exploit LLMs and use image-based methods. It’s very easy to get started on how to stop spam emails and block spam email addresses.

Remember that every step taken on how to stop spam emails contributes to a safer email environment. Utilizing the following 4 key multiple strategies on how to stop spam emails ensures better filtering in the era of AI:

• Identify inputs to your environment so you can manage your email environment using SPF/DKIM/DMARC with every email you send and receive, everywhere.
• Use layered, AI-native spam detection: leverage native filtering from Microsoft and Gmail to greatly reduce bad email and add Mesa to the mix for detecting AI-generated spam targeting your organization and users.
• Automate remediation: allow the systems to quarantine the threat without needing manual intervention letting them notify admin
• Review & iterate by regularly reviewing your security logs and updating rulesets.

Combining Mesa’s AI-native detection with cloud email vendors and authenticated email protocols like SPF/DKIM/DMARC gives organizations the necessary foundation to protect against the new wave of AI-assisted spam. Techniques on how to stop spam emails will evolve with the changing landscape of email threats but Mesa allows you to try AI-native detection for free today to see if it fits your organization’s needs.