List of the Top 20 Email Security Software for Microsoft 365 in 2026

Guardz is the unified cybersecurity platform built for MSPs. We consolidate the essential security controls, including identities, endpoints, email, awareness, and more, into one AI-native framework designed for operational efficiency. With an identity-centric approach, an elite threat hunting team, and 24/7 AI + human-led MDR, Guardz transforms cybersecurity from reactive defense into proactive protection.

NeoCertified protects confidential data through our secure email application, which operates seamlessly on our adaptable Cloud-based platform. It is accessible via any web browser and integrates with Microsoft Office 365/Outlook and Gmail, while also offering dedicated mobile applications for both iPhone and Android devices. Since our inception in 2002, we have been delivering secure mail solutions that comply with federal standards, enabling organizations to send and receive secure emails from any web browser or mobile platform. Our service is compatible with all email providers, ensuring that businesses enjoy the flexibility and robust security they require for their communications. Additionally, our commitment to constant innovation guarantees that we meet the evolving needs of our clients in an increasingly digital world.

SpamTitan's email security solution safeguards businesses, educational institutions, small to medium-sized enterprises (SMBs), and managed service providers (MSPs) from various email threats including spam. It effectively defends against phishing attempts, zero-day vulnerabilities, viruses, malware, ransomware, and other malicious email activities, ensuring a secure mail flow and filtering out unwanted messages. Our user-friendly yet robust email protection is compatible with Office365, making it accessible for a wide range of users. You can try SpamTitan Email Security risk-free with a fully supported trial. SpamTitan – Comprehensive features included: * Protection against CEO impersonation * Safeguarding against spear phishing attacks * Analysis of links within emails * Complete email sanitization * Defense against zero-day attacks * Mail spooling capabilities * Anti-spoofing measures * Protection against ransomware and malware * Checking for SPF, DKIM, and DMARC compliance * Encryption options available * Fully multi-tenant architecture * Customizable user interface for branding * Complete REST API access * Detailed setup documentation and support Recognized as a top solution in the G2 Crowd Email Security category, SpamTitan Email Security stands out for its premium functionalities and reliability. Begin your free trial today and enhance your email security!

Odix, recognized as a frontrunner in the Enterprise CDR (Content Disarm and Reconstruction) sector, has introduced FileWall, a dedicated cybersecurity application specifically designed for Microsoft Office 365 mailboxes. This innovative tool, FileWall™, integrates seamlessly with Microsoft security offerings such as EOP and ATP, providing comprehensive defense against unfamiliar threats posed by email attachments. Furthermore, FileWall™ maintains the integrity of sender-related security features, setting it apart from other Microsoft security solutions that may compromise these capabilities. By ensuring robust protection without sacrificing existing security measures, FileWall™ represents a significant advancement in email security.

Protect against ransomware, spam, phishing, and a range of other cyber threats that pose risks to small and medium-sized businesses, large enterprises, healthcare institutions, and government bodies, including their contractors. MailRoute provides API-level integration with platforms such as Microsoft Office 365 & GCC High, Google Workspace, and other email service providers, effectively reducing the likelihood of email-related attacks that could jeopardize sensitive information and systems. Our service delivers an affordable, multi-layered defense strategy that aligns with CMMC, NIST 800-171, HIPAA, and DFARS compliance, and is recognized by DISA for its email security capabilities. Built to eliminate any single point of failure, our fully owned infrastructure includes geo-distributed data centers that are outfitted with redundant network connections, power sources, and cooling systems, achieving a remarkable uptime of 99.999%. In addition, MailRoute combats email forgery and spoofing through sophisticated email authentication methods and managed DNS adjustments. By continuously overseeing and updating your email network security, we mitigate cyber threats and lessen risks like operational downtime, fostering both predictable costs and dependable services. Our ongoing commitment to reinforce email security reflects our determination to protect your digital assets from the constantly changing landscape of cyber threats, ultimately ensuring peace of mind for your organization. As the digital world evolves, so does our approach, adapting to new challenges to offer the best protection possible.

Effortlessly oversee email signatures for every user across all their devices. Designed specifically for Microsoft 365 and Google Workspace, this platform boasts decades of expertise in managing email signatures effectively. Ensure that all employees have consistent, professionally branded, and current signatures, regardless of their device, department, or location. You can also design targeted email signature marketing banners that appear beneath contact information to communicate updates, highlight achievements, showcase values, promote content, and much more, all featuring clickable calls-to-action to enhance engagement and drive traffic. With a role-based login system, the marketing or communications department can manage everything seamlessly. Once the initial setup is completed in just 45 minutes, IT teams are free from any ongoing responsibilities. The platform is securely hosted in ISO 27001-certified data centers, specifically on Microsoft Azure, guaranteeing optimal security for data storage in compliance with all laws and regulations, including GDPR. This robust framework not only safeguards sensitive information but also enhances user confidence in the management of their email communications.

Efficiently categorize deceptive emails while proactively detecting and isolating questionable URLs. Utilizing big data analytics enables precise classification of mass email communications. This comprehensive solution integrates seamlessly with both Google Workspace and Microsoft 365. Spambrella's Email Security and User Awareness Training technology is trusted by numerous leading security-focused organizations worldwide, spanning various industries and regions. By partnering with Spambrella, you can consolidate your email security strategies and user training initiatives on an international scale. Acting as your dedicated email security team, Spambrella ensures a smooth transition while possessing the technical know-how of other major providers like Symantec.cloud, Mimecast, and MxLogic. To safeguard your email users from potential threats, reach out today to arrange a demonstration with our cybersecurity specialists and enhance your email protection strategy.

LuxSci is dedicated to ensuring the safety of personal information while effectively safeguarding global communications. The company focuses on delivering web and email communication services that adhere to HIPAA regulations. LuxSci develops highly secure and tailored enterprise-level environments and solutions, empowering businesses to meet their unique operational and security requirements effectively. Among the offerings are services like Secure Email, Web, and Forms, which are designed to enhance data protection and facilitate compliance. In addition, LuxSci continuously evolves its services to adapt to the changing landscape of digital security.

Make a wise investment today to bolster your defenses against email security threats by acquiring a robust email security solution tailored for small businesses at affordable rates. Cybercriminals are increasingly targeting high-level executives like CEOs and CFOs across various sectors, alongside crucial departments such as HR and Accounting. While Office 365 offers some level of protection, its capabilities are insufficient to effectively combat impersonations, email fraud, and phishing attacks. Relying solely on custom transport rules to block domains and guard against employee impersonations can leave significant gaps in security. PhishProtection stands out as it is compatible with all email servers, devices, and SMTP services, ensuring comprehensive protection regardless of your location or the email client you use. Whether you access your emails through your phone, Outlook, or other platforms, this solution offers top-notch security for both Android and iOS devices, making it a critical investment for safeguarding your business communications. In today’s evolving cyber landscape, prioritizing email security is not just smart; it's essential for every small business.

Mailock secure email offers companies a reliable method for sharing sensitive information with clients while protecting their data from potential breaches. It employs advanced encryption technology combined with multi-factor identity verification, ensuring that confidential emails are effectively safeguarded against cyber threats, thereby keeping customer data secure. Users can effortlessly create secure emails from their desktop or browser, utilizing specific rules and keywords that activate encryption protocols. Furthermore, they have the ability to set up authentication barriers that verify the identities of recipients, guaranteeing that only those who are authorized can access the sensitive information. Each message is accompanied by comprehensive audit trails, allowing users to track recipient engagement through instant read receipts. Recipients are also given the option to encrypt their replies at no additional charge. This service not only promotes secure communication but also empowers clients to interact with your business in a safe manner. Additionally, it streamlines the delivery of confidential documents to clients in bulk through automated secure email processes, enhancing operational efficiency. Ultimately, Mailock fortifies the integrity and confidentiality of business communications, cultivating trust and security in all client interactions while ensuring compliance with data protection regulations.

Keepnet's comprehensive platform for managing human risk enables organizations to cultivate a culture of security through AI-enhanced simulations, personalized training, and automated responses to phishing attempts. This proactive approach significantly mitigates risks stemming from employees, insider threats, and social engineering tactics within the organization and beyond. By utilizing AI-driven phishing simulations across various channels such as email, SMS, voice, QR codes, MFA, and callback phishing, Keepnet perpetually evaluates human behaviors to minimize cybersecurity vulnerabilities. Furthermore, Keepnet's adaptive learning paths are customized for each employee, taking into account their risk profile, job role, and cognitive tendencies, thereby fostering secure practices over time. Employees are also empowered to promptly report any threats they encounter, while security administrators can react 168 times faster thanks to the platform's AI analysis and automated response capabilities. Additionally, Keepnet identifies employees who frequently engage with phishing links, mishandle sensitive information, or overlook security protocols, ensuring that organizations remain vigilant against potential breaches. This continuous cycle of assessment and adaptation is crucial for maintaining a robust defense against evolving cyber threats.

Libraesva Email Security serves as a robust defense for your organization against both longstanding and new email threats, guaranteeing that only authentic communications are delivered. It provides superior email protection by integrating cloud email solutions with a secure email gateway, further augmented by Libraesva's unique Adaptive Trust Engine. This innovative engine leverages artificial intelligence to analyze typical behavioral trends within organizations and their members, continually assessing the reliability of business communications and proactively identifying any suspicious activities. In addition, Libraesva Email Security thoroughly inspects all incoming and outgoing messages, effectively detecting and neutralizing advanced malware, phishing schemes, business email compromises, spam, and a variety of other potential hazards. Its exclusive sandboxing technology neutralizes dangerous payloads and active content found in attachments, while its proactive URL analysis examines every link, ensuring users are protected from visiting malicious websites. This comprehensive approach not only safeguards your organization’s communications but also enhances overall cybersecurity resilience.

At EmailAuth.io, which is affiliated with Infosec Ventures, our primary focus is safeguarding your most precious digital asset: your email. We are committed to enhancing your email deliverability, ensuring you receive the highest return on investment from your email campaigns, and fostering trust with your customers, partners, and vendors alike. Our approach goes beyond mere support; we take charge of the entire process! EmailAuth employs a strategy that encompasses the full journey toward achieving the highest level of security for your domains. Our team of security specialists, along with dedicated customer success managers, collaborates seamlessly with you to ensure your needs are met effectively. Together, we work towards a secure and trustworthy email experience for all your communications.

Smartlockr is a data security platform that prioritizes the needs of people to facilitate secure email and file sharing across entire organizations. By focusing on human factors, Smartlockr provides an intuitive interface designed to help users minimize the risk of data breaches, acknowledging that human error is the leading cause of such incidents globally. The platform is compatible with all operating systems and devices, and it conveniently integrates with existing systems, including a plug-in for Microsoft 365 (Outlook) and an SMTP relay service. Additionally, Smartlockr allows users to securely send and receive large files, accommodating sizes of up to 5 TB. Moreover, it adheres to strict privacy regulations and security standards, such as GDPR, ISO, and NTA 7516, ensuring comprehensive compliance for organizations. This commitment to security and user-friendliness makes Smartlockr an essential tool for modern organizations aiming to protect their valuable data effectively.

Utilize Trusted Email Identity to protect both employees and customers from sophisticated threats posed by email attacks. These advanced tactics take advantage of critical security vulnerabilities that standard email protection systems often overlook. Agari builds trust among employees, customers, and partners by maintaining the integrity of their inboxes. Its unique AI technology, which receives over 300 million updates each day, proficiently differentiates between genuine communications and malicious ones. Furthermore, global intelligence extracted from trillions of email exchanges provides valuable insights into user behavior and connections. With extensive experience in setting email security standards, Agari has established a benchmark that Global 2000 companies rely on, ensuring they are well-defended against emerging threats. This thorough strategy not only strengthens security measures but also cultivates confidence in all email communications. As a result, organizations can focus on their core operations while knowing their email systems are in safe hands.

Reliable and secure email hosting services are designed for businesses of all sizes, from small enterprises to large corporations. We oversee the secure handling of over 100 million emails monthly for our diverse clientele. Our offerings feature advanced gateway security, effective filtering mechanisms, inbound email protection, reliable email backups, and outbound SMTP services, all supported by state-of-the-art infrastructure to achieve the high standards expected by our clients. We also provide a secure email gateway, backup MX solutions, email forwarding, outbound SMTP, and a variety of additional features. DuoCircle stands out by offering strong defenses against phishing attacks through its Link Click Protection, which is a part of the Advanced Threat Defense Suite. This innovative feature guarantees protection even if a website's content changes between clicks, keeping potential threats at bay. With Link Click Protection, sensitive corporate data is well-protected, as employees are prevented from visiting sites that could exploit this information. Moreover, you will receive prompt notifications when there’s an attempt to click on a suspicious link, ensuring that your security is always prioritized. In summary, our extensive email security solutions significantly bolster the safety of your communications while providing assurance for your organization’s data integrity. Furthermore, we are committed to continuously enhancing our services to meet the evolving demands of today’s digital landscape.

Proofpoint's Adaptive Email Security offers a robust and comprehensive defense against a range of email-related threats, including phishing and Business Email Compromise (BEC). This innovative solution employs behavioral AI technology that adapts to evolving threats, ensuring immediate protection during the email delivery process. By consolidating email security into a unified platform, organizations can simplify operations, reduce the challenges associated with multiple vendors, and achieve significant savings in both time and resources. Additionally, it features advanced capabilities such as internal mail protection, real-time user coaching, and a holistic overview of email security, making it essential for protecting sensitive communications and ensuring compliance with regulations. Implementing this solution not only strengthens an organization's security framework but also promotes a more streamlined workflow across their email operations, ultimately leading to greater productivity. As businesses increasingly rely on digital communications, having such a comprehensive security solution becomes indispensable for maintaining trust and integrity in their interactions.

A remarkable 98% of organizations using Microsoft 365 experience harmful emails infiltrating their inboxes. The Barracuda Email Threat Scanner has identified over 10 million spear-phishing attempts hidden within the email systems of numerous companies. Over 16,000 organizations have utilized this scanning service and discovered serious threats in their email accounts. This complimentary service allows users to see results just minutes after the scan is initiated. Our AI-driven platform is tailored to analyze the intentions of email senders, facilitating the detection of social engineering risks. Users can obtain comprehensive insights regarding each email threat, categorized by time, employee, and type of threat, along with an evaluation of their domain's DMARC status. It is crucial to recognize that email threats do not impact all employees uniformly. By analyzing job titles, assessing risk factors tied to communications, and counting the total number of attacks aimed at specific individuals, organizations can identify who within their workforce is most susceptible to these threats. Recognizing these dynamics plays a vital role in strengthening the overall cybersecurity posture of a business. Ultimately, being proactive in these areas can greatly enhance an organization's defense against email-based attacks.

Sublime revolutionizes traditional black box email gateways through the integration of detection-as-code and collaborative community initiatives aimed at bolstering security measures. Its binary explosion feature conducts a thorough examination of attachments and files automatically retrieved via links, effectively detecting threats such as HTML smuggling, suspicious macros, and various harmful payloads. In addition, Natural Language Understanding plays a crucial role in analyzing the tone and intent of messages, leveraging the sender's historical interactions to reveal attacks that may not rely solely on payloads. The Link Analysis tool, enhanced by a headless browser, meticulously renders web pages while employing Computer Vision to analyze content for counterfeit brand logos, fraudulent login pages, captchas, and other potentially dangerous components. Additionally, sender analysis incorporates organizational context to identify impersonation attempts aimed at high-value users, thereby providing an extra layer of security. Furthermore, Optical Character Recognition (OCR) adeptly extracts essential entities from attachments, such as callback phone numbers, which are vital for detecting phishing schemes. This comprehensive suite of features allows organizations to proactively safeguard their communications against a wide range of evolving threats.

Easily detect and eliminate phishing threats, which encompass malware transmitted via email, business email compromises, and various multi-channel (link-driven) attacks. Enhance your defenses against targeted phishing initiatives that use both email and an assortment of applications to take advantage of users and gain unauthorized access. Experience superior threat detection that requires minimal adjustments to policies and settings, allowing you to conserve time, reduce costs, and enjoy peace of mind while identifying phishing threats that may evade others. Start with a complimentary phishing retro scan to reveal any active threats hidden in your inboxes, and also consider requesting a free phishing risk assessment to gauge the effectiveness of your existing security protocols. It is crucial to maintain ongoing protection against both traditional and emerging phishing tactics, including those designed to circumvent standard security measures. Safeguard your workforce from link-based threats that may target users across various platforms, such as QR-code and deferred attacks, thereby bolstering your overall organizational security. By adopting these preventative strategies, you not only reinforce your defenses but also foster a culture of security awareness within your organization, ultimately empowering your employees to recognize and report potential threats. This proactive approach can significantly reduce the likelihood of a successful phishing attack.