Best Mail Servers in the USA

The MDaemon Email Server was one of the first Microsoft Exchange alternatives offered to businesses around the world. It has been developed with the ongoing input from IT professionals seeking an easy-to-use, reliable, and secure mail server that does not require expensive administration or impose high per-user costs. It simplifies messaging and collaboration with a focus on security and privacy, an intuitive, user-friendly web mail design and by offering administrators Mobile Device Management, Business Instant Messaging, Document Sharing, and other enterprise-class features that can be managed with minimal support. MDaemon Email Server supports IMAP, SMTP, and POP3 protocols, and features include: integrated webmail with IM and document sharing, Outlook support, compromised password alerts, color-coded log files for quick and easy troubleshooting, customizable email policy setting to fit your unique network environment, Mobile Device Management, Account Hijack Detection, and more.

KumoMTA is an Open-Source, enterprise-grade email message transfer agent (MTA) software for sending high-volume, business-critical emails. KumoMTA is typically chosen by high-volume email users looking to replace PowerMTA, Momentum, or traditional Open Source MTAs. KumoMTA offers high-performance message relay to the tune of millions of messages per hour per server, combined with extreme flexibility and configurability through its use of a Lua scripting engine for configuration and message management. For more information on KumoMTA see our Sourceforge project page.

XgenPlus is a next-generation, feature-rich, and highly secure email solution designed to meet the growing communication needs of businesses, enterprises, and individuals. Developed by Bharat Sync Technologies Pvt. Ltd., Xgen Email stands out as the first email service in the world to support Internationalized Domain Names (IDN), enabling users to create email addresses in multiple Indian languages such as Hindi, Gujarati, Tamil, Telugu, Punjabi, and Urdu. With cutting-edge security features, real-time tracking, advanced collaboration tools, and seamless mobile and desktop integration, Xgen Email ensures that users get the most efficient, private, and productive email experience. Whether you're a startup, a large enterprise, or an individual professional, Xgen Email is the best choice for a secure, smart, and efficient email solution.

KingSMTP.com (formerly known as Kingmailer.co, founded in 2017) is a Transactional SMTP service provider. It’s designed to help businesses reliably send emails such as order confirmations, password resets, or notifications, but it’s not intended for mass email campaigns or marketing.

SmarterMail is the ideal Microsoft Exchange alternative. It’s the only business email server on the market that offers native support for Exchange protocols: MAPI, EWS, and EAS, without requiring any additional software or plug-ins for Microsoft Outlook or other desktop or mobile clients. It delivers all the features of Exchange at a fraction of the cost. SmarterMail also includes audio/video group chat and Online Meetings for team collaboration at no extra charge. Its newest feature, the SmarterMail Marketplace, enables seamless integration with platforms like OnlyOffice, Collabora, and AI tools such as OpenAI’s ChatGPT. Available for both Windows and Linux, SmarterMail has lower hardware requirements, superior stability, and reduced maintenance costs. It’s the perfect solution for businesses of any size or industry seeking Exchange-level functionality, without the high costs.

Offer your customers secure, business-level email hosting with various value added services. An excellent solution for SPs, suitable for thousands to millions of users. Acquire new customers by offering a premium email server solution with a high degree of flexibility, allowing you to automate it within your existing infrastructure. Manage your email, organize and share calendars, sync your mobile devices, all based on a secure and powerful mail server. The perfect answer for businesses of all sizes. Axigen is quite knowledgeable, out of the many hats it wears, take a peek inside and choose what fits you. Manage your email and get stuff done easily with calendars, tasks or notes. Enjoy desktop usability in your browser via keyboard navigation and shortcuts, drag-and-drop, "live" email list view, frequent folders, email filters, out-of-office messages, individual blacklist / whitelist.

SOGo is a fully supported and trusted groupware server with a focus on scalability and open standards. SOGo is released under the GNU GPL/LGPL v2 and above. SOGo provides a rich AJAX-based Web interface and supports multiple native clients through the use of standard protocols such as CalDAV, CardDAV and GroupDAV, as well as Microsoft ActiveSync. SOGo is the missing component of your infrastructure; it sits in the middle of your servers to offer your users a uniform and complete interface to access their information. It has been deployed in production environments where thousands of users are involved.

The only office rule is, there is no office. Business email, TeamChat for project teamwork, real-time office document collaboration and online meetings. All in our secure cloud and for half the usual cost. Chat in teams organized around projects, upload files, mention coworkers, comment on posted emails, pin important posts. Integration with email enables sharing received messages directly to TeamChat room for colleagues‘ attention. Skyrocket your office work effectivity with Desktop Client and Desktop Office documents on Windows as well as Linux devices. Get the complete Suite, or choose only the app you need.

Our end to end Unified Communications technology begins with the platform CommuniGate Pro. The system enables large scale Unified Communications with open API’s for integration into business applications. CommuniGate Pro scales dynamically to 100’s of millions of accounts. Ideally suitable for “Nation” scale alert systems, multimodal communications within web applications, or compartmentalized high-security network topologies. However, big scale does not mean trade-offs on efficiency or reliability. The platform is extremely agile for resilient applications in military or embedded environments. CommuniGate Pro is approved for governmental agency use in Europe and in the USA. Military, transportation and research center use is legendary for mind bending stability with uptimes like VMS. CommuniGate Pro enables banks to deploy mail to millions of clients for online self care while respecting compliance regulations. The signaling features of the server can be deployed in a hybrid system.