Alternatives to Postfix
Compare Postfix alternatives for your business or organization using the curated list below. SourceForge ranks the best alternatives to Postfix in 2026. Compare features, ratings, user reviews, pricing, and more from Postfix competitors and alternatives in order to make an informed decision for your business.
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1
Greatmail
Greatmail
Dependable cloud based email hosting with spam filtering, antivirus protection, generous storage and webmail. Compatible with Outlook and all other POP3/IMAP clients. High volume SMTP service for responsible senders. Outbound relay service for transactional messages, email marketing campaigns, newsletters and other applications. Dedicated email servers, clustering and multiple IP load balancing for high volume senders. Fixed monthly cost with unlimited sending and reputation monitoring. Greatmail is an email service provider (ESP) specializing in business class email hosting, SMTP hosting and email servers. For ISPs, application programmers and cloud developers, we also provide custom solutions including dedicated IP servers and process specific, load balanced configurations with multiple servers. -
2
SendGrid
Twilio SendGrid
Email is the backbone of your customer engagement. The Twilio SendGrid Email API is the email service trusted by developers and marketers for time-savings, scalability, and delivery expertise. Our flexible Email API and proprietary Mail Transfer Agent (MTA), intuitive console, powerful features, and email experts make it easy to ensure all your email gets delivered in seconds and without interruption. Monitor engagement data and optimize deliverability with our Deliverability Insights dashboard. Whether you’re sending 100 emails or 100 billion, SendGrid is built to scale. Integrate with our RESTful APIs and SMTP in minutes, with sample code libraries available in 7 languages, interactive docs, templates, and more.Starting Price: $19.95 per month -
3
SMTP.com
Ziff Davis
Reliable SMTP relay and email delivery services. Powerful email delivery services that enable you to send and track high volume emails effortlessly. Integrate and start sending in minutes. All your transactional, email relay and email delivery needs under one roof. Whether you need a low-latency email delivery provider for your transactional emails, scalable infrastructure for high-volume sends or reliable backend solution for your marketing campaigns, SMTP is built to deliver. Reputation Defender is SMTP’s proprietary technology that uses big data to proactively monitor your email list health and safeguard your domain and IP reputation among ISPs by suppressing bad emails in your sends from hard and soft bounces. This ensures your delivery rates and inbox placement incrementally gets better over time.Starting Price: $25 per month -
4
Apache James
The Apache Software Foundation
James stands for Java Apache Mail Enterprise Server. It has a modular architecture based on a rich set of modern and efficient components which provides at the end complete, stable, secure, and extendable Mail Servers running on the JVM. Create your own personal solution of email treatment by assembling the components you need thanks to the Inversion of Control mail platform offered and go further customizing filtering and routing rules using James Mailet Container. The Apache James project wires together the different libraries composing James to provide running services, ready to download on the Apache mirrors.Starting Price: Free -
5
Dovecot
Dovecot
Dovecot is an excellent choice for both small and large installations. Dovecot is among the best performing IMAP servers while still supporting the standard mbox and Maildir formats. The mailboxes are transparently indexed, which gives Dovecot its good performance while still providing full compatibility with existing mailbox handling tools. Dovecot is standards compliant. Dovecot passes all IMAP server standard compliancy tests while most other servers fail many of them. Dovecot’s indexes are self-optimizing. They contain exactly what the user’s client commonly needs, no more and no less. Dovecot is self-healing. It tries to fix most of the problems it notices by itself, such as broken index files. The problems are however logged so the administrator can later try to figure out what caused them. Dovecot tries to be admin-friendly. Common error messages are made as easily understandable as possible.Starting Price: Free -
6
Exim
Exim
Exim is a mail transfer agent (MTA) used in Unixllike operating systems. The first version was written in 1995 by Philip Hazel for use in the University of Cambridge Computing Service's e-mail systems. Exim is distributed under the GPL, and therefore is free to download, use and modify. Exim somewhat resembles Smail 3, but it has diverged and now surpasses it in user friendliness and flexibility. They both follow the Sendmail design model where a single main binary controls all the facilities of the MTA. This monolithic design is considered by some to be inherently less secure and slower, but despite this, Exim's security record is much better than Sendmail and comparable with Qmail and Postfix, as is its speed. In advanced areas such as queue handling, address routing and testing, it exhibits excellent performance. Exim doesn't have a Graphical User Interface (GUI) to help you configure it, but some Linux distributions add one. -
7
Halon
Halon
Halon reinvents email infrastructure for today’s fast-moving, high-volume world. Their solutions- Halon Engage, Halon Protect, and Halon Classify offer a fully composable platform that empowers you to define, control, and automate every aspect of your email infrastructure stack with intelligence built in. Ideal For: - Enterprises or platforms sending high volumes of transactional, marketing, or lifecycle emails - Email service providers (ESPs) looking for more control and agility - Teams who want real-time visibility, proactive delivery, and the ability to evolve on their own terms Benefits: - Develop features 10x faster - Reduce manual triage - Decrease traffic jams - Reduce escalations - Keep your email operations teams happier - Supercharge client satisfaction - Increase your top line and grow your business -
8
Mail-in-a-Box
Mail-in-a-Box
Mail-in-a-Box lets you become your own mail service provider in a few easy steps. It’s sort of like making your own gmail, but one you control from top to bottom. Technically, Mail-in-a-Box turns a fresh cloud computer into a working mail server. But you don’t need to be a technology expert to set it up. Each Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software. It also includes contacts and calendar synchronization. The box also includes other standard mail functionality like spam protection (spam filtering and greylisting), mail filter rules, email client autoconfiguration, and automated backups to Amazon S3 and other services. The box also includes automatic DNS configuration when you let it become your nameserver so that it can set important DNS records for mail deliverability and security including SPF, DKIM, DMARC, and MTA-STS. When enabled, DNSSEC (with DANE TLSA) provides a higher level of protection.Starting Price: Free -
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MailerQ
MailerQ
MailerQ is a high-performance on-premise Mail Transfer Agent (MTA) for delivering millions of emails per day. It is built with a strong focus on performance, ease-of-use, and insights. The MTA comes packed with an intuitive Management Console, REST API, and other functionality necessary for every serious sender to retain and improve their sender reputation and deliverability rates. That’s why it's increasingly becoming the preferred solution of choice for senders of all kinds, from Email Service Providers and e-commerce platforms to banks and government institutes. The management console allows for real-time insights in delivery attempts and results, queues, error logs and a lot more per MTA, IP, target and even per customer, campaign or message type. Response patterns allow you to classify bounces, process feedback loops and adapt MTA behavior based on server responses. This will help you maximize your email deliverability and sender reputation.Starting Price: €10,000 one-time payment -
10
Modoboa
Modoboa
Regain your independence and protect your privacy by installing your own email server. It takes less than 10 minutes! Create your mail server for free in less than 10 minutes with Modoboa When it comes to create a mailbox, you generally have several solutions: - Use the services offered by Internet providers (Orange, Vodafone...) of infrastructure providers (OVH, Gandi...) with a monthly or annual subscription. However, customization and configuration possibilities, domains and mailboxes number are limited. - Use the services of free email providers (Gmail, Live, Yahoo...) which are limited and your data is used for commercial purposes. - Install your own email server, which requires important technical knowledge to setup and configure the system. Modoboa is an alternative to those 3 options. It frees you from dependence on email providers and makes accessible to all the creation his own secure email server. The whole thing, in less than 10 minutes and freely.Starting Price: Free -
11
MDaemon Email Server
MDaemon Technologies
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.Starting Price: $360 per year -
12
SquirrelMail
SquirrelMail
SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. It has very few requirements and is very easy to configure and install. SquirrelMail has all the functionality you would want from an email client, including strong MIME support, address books, and folder manipulation. The need arose in our organization for the access of email and address books from anywhere in the world. Obviously a web interface is ideal for this, given that the user has access to the Internet. After reviewing several open source projects we realized that we were going to need to do some fairly major customizations to get things to be a nice fit for our needs. -
13
Sendmail
Proofpoint
The sendmail Sentrion platform is specifically designed for large, complex environments, but we make a subset of that solution available as an open-source offering. Sentrion is not for everyone, but if you are using open source email for a large complex environment and need an enterprise platform that will enable your messaging roadmap for years to come (virtualization, consolidation, cloud migration, etc.). The Domain Keys Identified Mail (DKIM) Internet standard enables email senders to digitally sign their messages so that receivers can verify that those messages have not been forged. The DKIM sender authentication scheme allows the recipient of a message to confirm a message originated with the sender’s domain and that the message content has not been altered. A cryptography-based solution, DKIM provides businesses an industry-standard method for mitigating email fraud and protecting an organization’s brand and reputation at a relatively low implementation cost. -
14
Zimbra
Synacor
Zimbra 9 : Extensibility for Collaboration Superheroes! Users move seamlessly between desktop, mobile and tablet browsers with a consistent email and collaboration experience. Designed for extensibility and features best- in-class, out-of-the-box integrations with Slack, Dropbox and Zoom, with many more underway. Zimlet framework and APIs let you customize Zimbra to meet your specific requirements. Zimbra’s dependable server infrastructure for the security, privacy and data sovereignty Zimbra customers expect. Expect an easy upgrade process moving to Zimbra 9 — with no data migration. Zimbra 9's modern, responsive UI is built on Zimbra's dependable server infrastructure for the security, privacy and data sovereignty you expect from Zimbra. Unlike competitors with closed platforms, Zimbra 9 is flexible and extensible. Break free from Microsoft and Google and integrate with the 3rd party collaboration services you use today—Slack, Zoom, Dropbox and more.Starting Price: Varies -
15
iRedMail
iRedMail
The right way to build your mail server with open source softwares. Works on CentOS Stream, Rocky, Alma, Debian, Ubuntu, FreeBSD, OpenBSD. With iRedMail, you can deploy an OPEN SOURCE, FULLY FLEDGED, FULL-FEATURED mail server in several minutes, for free. We did the heavy lifting of putting all the open source components together and applying best practices. Our product does all the major tasks for you. Furthermore we offer professional support to back you up in case you have some problems. You have all personal data on your own hard disk, you can control the email security, inspect transaction log. No other organization can see the content of all messages. All components used in iRedMail are open source softwares, and you get the bug fixes and updates from the Linux/BSD venders you trust. iRedMail is the right way to build your mail server with open source softwares.Starting Price: Free -
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mailcow
mailcow
mailcow: dockerized is an open source groupware/email suite based on Docker. mailcow relies on many well known and long used components, which in combination result in an all around carefree email server. Each container represents a single application, connected in a bridged network.Starting Price: Free -
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hMailServer
hMailServer
hMailServer is a free, open source, e-mail server for Microsoft Windows. It's used by Internet service providers, companies, governments, schools and enthusiasts in all parts of the world. It supports the common e-mail protocols (IMAP, SMTP and POP3) and can easily be integrated with many existing web mail systems. It has flexible score-based spam protection and can attach to your virus scanner to scan all incoming and outgoing email.Starting Price: Free -
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qmail
qmail
qmail is a secure, reliable, efficient, simple message transfer agent. Security isn't just a goal, but an absolute requirement. Mail delivery is critical for users; it cannot be turned off, so it must be completely secure. qmail's straight-paper-path philosophy guarantees that a message once accepted into the system, will never be lost. qmail also optionally supports maildir, a new, super-reliable user mailbox format. Maildirs, unlike mbox files and mh folders, won't be corrupted if the system crashes during delivery. Even better, not only can a user safely read his mail over NFS, but any number of NFS clients can deliver mail to him at the same time. qmail is vastly smaller than any other Internet MTA. Other MTAs have separate forwarding, aliasing, and mailing list mechanisms. qmail has one simple forwarding mechanism that lets users handle their own mailing lists. -
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Postfix
AXSMarine
AXSMarine’s Postfix is an AI-powered, Outlook 365 plugin and document management system built specifically for the complex post-fixture phase in maritime chartering. Once a fixture is confirmed, Postfix automatically identifies, normalizes, and tags fixture-related data from emails and documents, such as recaps, CPs, port logs, and correspondence, transforming fragmented communications into structured, searchable records. Via the Outlook plugin, users can file communications directly into a customizable, secure storage environment (AXSDrive), preserving familiar folder structures. Integrated smart forms and business intelligence dashboards then provide actionable insights through KPIs, filters (by broker, commodity, office, etc.), and analytics tools for enhanced operational visibility and strategic planning. With support for compliance workflows, audit trails, and seamless API-based integrations into broader systems, Postfix streamlines post-fixture workflows. -
20
Rspamd
Rspamd
Rspamd has been started to handle mail flows that has grown over the last decade by more than ten times. From the very beginning of the project, Rspamd was oriented on highly loaded mail systems with development focus on performance and scan speed. Rspamd is written in plain C language and it uses a number of techniques to run fast especially on the modern hardware. On the other hand, it is possible to run Rspamd even on an embedded device with a very constrained environment. You can also check the recent performance analyze article to have a better impression about how fast Rspamd could be. Rspamd can be treated as a faster replacement for SpamAssassin mail filter with the ability to scan ten times more messages using the same rules (by means of SpamAssassin plugin). In the next graph, you can see how switch to Rspamd from SA helped to reduce CPU load on scanner machines. Rspamd can work with the most popular mail transfer systems, such as Postfix, Exim, Sendmail or Haraka. -
21
Haraka
Haraka
Haraka can serve thousands of concurrent connections and deliver thousands of messages per second. Haraka and plugins are written in asynchronous JS and are very fast. Haraka has very good spam protection (see plugins) and works well as a filtering MTA. It also works well as an MSA running on port 587 with auth and dkim_sign plugins enabled. Haraka makes no attempt to be a mail store (like an exchange or postfix/exim/qmail), an LDA, or an IMAP server (like Dovecot or courier). Haraka is typically used with such systems. Haraka has a scalable outbound mail delivery engine built in. Mail marked as relaying (such as via an auth plugin) is automatically queued for outbound delivery. Haraka's plugin architecture provides an easily extensible MTA that complements traditional MTAs that excel at managing mail stores but do not have sufficient filtering.Starting Price: Free -
22
ClrStream
Mithi Software Technologies
29% of businesses that face a data breach end up losing revenue. And email is the #1 target of attack. Secure your email systems with ClrStream. A security and continuity solution for MS Exchange, Office 365, MDaemon, Postfix, Postmaster, Zimbra & other mail solutions. 88% of businesses experience data loss and email is the main culprit. An email scrubbing solution with guaranteed protection from Malware, Ransomware, Virus and Spam. Low latencies for mail delivery and a low rate of false positives. A peripheral, out-of-environment solution to mitigate DDOS attacks. A solution that can provide email Continuity when the primary mail server is unavailable or down. A solution offering with built-in redundancies and scale eliminating the need for a mail parking service. A cloud-based SaaS solution that helps de-congest bandwidth and eliminates management headaches. -
23
zdaemon
Python Software Foundation
zdaemon is a Unix (Unix, Linux, Mac OS X) Python program that wraps commands to make them behave as proper daemons. zdaemon provides a script, zdaemon, that can be used to run other programs as POSIX (Unix) daemons. (Of course, it is only usable on POSIX-complient systems.) Using zdaemon requires specifying a number of options, which can be given in a configuration file, or as command-line options. It also accepts commands teling it what to do. Start a process as a daemon. Stop a running daemon process. Stop and then restart a program. Find out if the program is running. Send a signal to the daemon process. Reopen the transcript log. Commands can be given on a command line, or can be given using an interactive interpreter. We can specify a program name and command-line options in the program command. Note, however, that the command-line parsing is pretty primitive.Starting Price: Free -
24
Microsoft SMTP Service
Microsoft
Microsoft SMTP Service is a mail server software that enables Microsoft Windows Server operating systems to send and receive emails. It is a component of Internet Information Services (IIS) and is used to relay emails between mail servers. Microsoft SMTP Service is a popular choice for organizations that need a reliable and scalable mail server solution. It is easy to install and configure and can be used with a variety of email clients. Microsoft SMTP Service supports a number of features, including: Relaying emails between mail servers: Microsoft SMTP Service can relay emails between mail servers, which means that it can be used to send and receive emails for multiple domains. Supporting multiple email clients: Microsoft SMTP Service can be used with a variety of email clients, including Microsoft Outlook, Mozilla Thunderbird, and Apple Mail. Providing security features: Microsoft SMTP Service provides a number of security features, such as authentication and encryption -
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Bit SMTP
Bit Apps
Many site owners face the spam mail problem for using the WordPress default PHP mail function. There may be some restrictions when it comes to mail service: sometimes emails are not delivered, sites cross the limit of outgoing mail. Bit SMTP plugin allows you to authenticate the mail service of your site by configuring the SMTP server of your desired mail service. SMTP is a protocol that helps your WordPress site make its email deliverability more easygoing & reliable. By enabling this feature, you can send mail from your site to your recipients via your preferred mail server. -
26
Argent
Argent Software
Argent Guardian® Ultra is the world's most scalable monitoring solution for all Windows, Linux, UNIX (AIX, HP-UX, SCO, Solaris), and iSeries Servers. Using a patented agent-optional architecture, Argent Guardian® Ultra monitors servers with or without installing agents, providing the power and flexibility to define the monitoring architecture to match customers' exact needs. The days of manually scheduling and managing batch processes are over. Business process automation lowers overall IT costs, ensures application efficiency, enhances IT service and assists with compliance requirements. Argent Job Scheduler and Argent Queue Engine automate business processes, alert customers via Argent Console when issues occur and provide Service Level Agreements so that management receives the Business View of IT. Argent Job Scheduler provides a single point of control across all operating systems, applications and databases for Windows, Linux, Solaris, HP-UX, AIX, SCO and iSeries Servers. -
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Unison File Synchronizer
Unison
Unison is a file-synchronization tool for OSX, Unix, and Windows. It allows two replicas of a collection of files and directories to be stored on different hosts (or different disks on the same host), modified separately, and then brought up to date by propagating the changes in each replica to the other. Unison runs on both Windows and many flavors of Unix (Solaris, Linux, OS X, etc.) systems. Moreover, Unison works across platforms, allowing you to synchronize a Windows laptop with a Unix server, for example. Unlike a distributed filesystem, Unison is a user-level program: there is no need to modify the kernel or to have superuser privileges on either host. Unison works between any pair of machines connected to the internet, communicating over either a direct socket link or tunneling over an encrypted ssh connection. It is careful with network bandwidth and runs well over slow links such as PPP connections. -
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SocketLabs
SocketLabs
SocketLabs is a reliable email delivery engine built designed to help companies of all sizes send marketing and transactional email fast and easy. Trusted by leading organizations such as Virgin and the American Red Cross, SocketLabs combines a feature-rich outgoing mail server delivery solution, an easy-to-use dashboard interface, and an even easier setup. It also features outgoing mail servers, advanced analytics, and top notch customer support. -
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WP Mail SMTP
WP Mail SMTP
If you're having issues with WordPress not sending emails, you're not alone. With the rise of aggressive spam filtering, it's tough to reach the inbox unless your emails are configured correctly. Once you've switched from the default WordPress email settings over to WP Mail SMTP, your email deliverability issues will be solved for good. Are you missing out on leads and sales because emails sent from your WordPress site are ending up in the spam folder? Missing out on these opportunities can be a big hit to your bottom line. When your emails are properly authenticated using SMTP, they'll be recognized as legitimate and bypass those aggressive spam filters. WP Mail SMTP integrates with all of the best secure SMTP providers. No matter how many emails you need to send, you can connect with the right provider for your business needs and budget.Starting Price: $49 per year -
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SMTP Provider
SMTP Provider
Experience the next level Email Marketing at an affordable price. Use a dedicated IP address to increase your sender reputation and avoid blacklisting of your IP due to someone else’s actions. Show that it’s really your own company and domain sending the message, and minimize the amount of messages that are marked spam by using the special cryptographic signatures SPF and DKIM. Our SMTP servers send your emails using secure SSL connection. Moreover, it's lightning fast. For each mailing list, you can discover the amount of messages sent out, the number of conversions made and links clicked, and many other details. Our SMTP service generates sending reports and delivery error reports. All reports can be downloaded to your computer. Your mailings won’t be sent to any addresses on the list of recipients who have unsubscribed, even if they are on a mailing list. Make sure that your emails are delivered to the inbox and not the spam folder. -
31
Xeams
Synametrics Technologies
Xeams is, a secure and powerful complete mail server for Windows, Linux, Solaris, MacOSX and other flavors of UNIX. Xeams supports SMTP, POP3, and IMAP. It features a powerful spam filtering engine that eliminates up to 99% of junk email upon installation. The software offers a flexible approach to email, making it a very user-friendly server. Xeams can block 99% percent of all junk messages right out of the box. The filtering rules are fully customizable and get better as Xeams adapts to your email environment. IMAP and POP3 servers built right into the system to easily fetch emails from an email repository to a client's machine. Xeams can be used as an email firewall in front of another server, such as MS Exchange, or as a full email server requiring no other software to process emails. Use Xeams in front of your Office 365 infrastructure to gain additional filtering, reporting and archiving capabilities that you don't get with Office 365 alone.Starting Price: $20.00/year/user -
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AuthSMTP
AuthSMTP
AuthSMTP is the outgoing SMTP email service for your e-commerce website, mailing list or email application on most current computers and mobile devices. With instant setup, a money back guarantee and very low cost starter accounts you can test and start sending email in minutes with no risk. Our systems are custom designed / built for reliability and performance when processing and delivering very high volumes of email. We use high performance and redundant systems to help ensure we can provide the highest levels of availability. We provide an online Control Panel plus email and web based support backed by knowledgable support staff on hand to provide help if required. We have over 15 years experience providing email services and getting emails delivered quickly and accurately to your recipients.Accounts are created instantly when you sign up so with our setup guides you can start sending email within minutes.Starting Price: $36 per year -
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Postmastery
Postmastery
Postmastery provides a platform for professional email monitoring that goes far beyond the obvious ‘click & open’ statistics. Postmastery’s Delivery Analytics platform processes SMTP delivery data from both on-premises mail servers and SMTP providers. It reads data from Microsoft SNDS, Return Path Sender Score and relevant blacklists. Users have access to real time dashboards and receive automatic alerts. High bounce rates, increased delivery times, junk foldering or blacklisting are serious problems in email marketing and they impact your business. Since they affect your reputation , it's best to stay ahead of them. Postmastery offers a baseline for improvement and carries out an email delivery assessment. And, if needed, our specialists provide hands-on support at infrastructure level as well. Focus on your core business and outsource your delivery monitoring to Postmastery. Email delivery experience, expertise and tooling is at your disposal via our 'email delivery control centre'. -
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mySMTP
mySMTP
Send email to whoever you wish with unlimited capacity and traffic. The mail server works regardless of whether you are using your desktop computer at home or a laptop, tablet or telephone while you’re on the move. Avoid blacklistings and forget maintenance, updates, down time and other hindrances. We send your email campaigns to the entire world via stable SMTP cloud servers. If you choose a dedicated SMTP cloud server, you send email using your own IP number and domain. This gives you full control of the reputation of what you send. If you need a fullscale professional system to handle email lists and make state of the art email content - we offer Mailwizz. More emails are sent than ever before and there is still no new product on the market that looks like it would be able to replace email as the direct route to the attention of the recipient. When it comes to marketing, email gets the highest marks for return on investment with regard to advertising in social media, for example. -
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EmailSuccess
DIENNEA SRL
EmailSuccess is an enterprise-level SMTP Server for high volume email sending. EmailSuccess is an MTA (Mail Transfer Agent) solution for senders of any size: ESPs and Marketing Automation Companies. High Performance EmailSuccess is an MTA designed to deliver high email volumes, giving the business full control over Speed, Latency, Reliability and Deliverability parameters. Deliverability Deliverability is key for the clients to reach their target easily. Ensure that the email has the best chance of avoiding spam filters and landing in the inbox. Advanced Sending Intelligence Optimized delivery by tuning email delivery parameters automatically and in real-time; making platform tuning ever so easy.Starting Price: $0 - $4000 -
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OutboundSMTP
OutboundSMTP
DKIM Signing improves the inbox placement of mailbox providers like Gmail, Office365. Multiple Servers in the USA and Europe for increased reliability. No more headaches of managing and maintaining your own email server and IP reputation. Create SPF and DKIM records for your domain names, no prior experience required. If you are suffering from an IP blacklisting our SMTP relay service can solve your reputation problems. 24×7 technical support via phone, chat or email. We are here to ensure your mail gets delivered. you’ll be able to deliver your mail reliably to the inbox. We optimize our sending routes and closely monitor our IP reputations to ensure you the best possible service. We have a Zero Spam Policy that allows us to block or restrict messages that would damage our reliability or the reputation of our customers. You may send from an unlimited number of “From” addresses or domains after you have verified your domain ownership via DNS.Starting Price: $4 per 2,500 messages -
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ActFax
ActFax Communication-Software
ActFax the fax server software for Windows and Unix. As a leading product for company-wide integration of network fax solutions, ActFax sets standards for years. Fax messages are sent from any workstation and any application in a matter of seconds. Many major companies from different business lines all over the world are our customers and trust in ActFax. The client/server architecture of ActFax stands for a fast and simple integration of fax and email with Windows as well as other operating systems, like Unix (i.e. AIX, HP-UX, Solaris), Linux, DOS or mainframes. The software also offers full support for terminal server and Citrix (XenApp) environments. The connection to the public switched telephone network can be done through analog lines, ISDN, VoIP/FoIP, SIP and T.38, as well as Web Fax Providers. The easy integration of ActFax into own applications is used for fully automated fax transmissions. -
38
Bash
Bash
Bash is a free software Unix shell and command language. It has become the default login shell for most Linux distributions. In addition to being available on Linux systems, a version of Bash is also available for Windows through the Windows Subsystem for Linux. Bash is the default user shell in Solaris 11 and was the default shell in Apple macOS from version 10.3 until the release of macOS Catalina, which changed the default shell to zsh. Despite this change, Bash remains available as an alternative shell on macOS systems. As a command processor, Bash allows users to enter commands in a text window that are then executed by the system. Bash can also read and execute commands from a file, known as a shell script. It supports a number of features commonly found in Unix shells, including wildcard matching, piping, here documents, command substitution, variables, and control structures for condition testing and iteration. Bash is compliant with the POSIX shell standards.Starting Price: Free -
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HP-UX
Hewlett Packard Enterprise
Highly integrated UNIX operating system and tools that deliver the highest availability, reliability, and security on mission-critical HPE Integrity servers. Streamline your operations using a highly integrated UNIX operating system with tools that delivers the highest reliability, availability, and security on mission-critical HPE Integrity servers. HP-UX gives you a dynamic, secure, and unified environment and comes pre-integrated on mission-critical HPE Integrity servers. Meet your specific UNIX mission-critical requirements. HP-UX offers four operating environments tailored to specific needs. Holistic server security and system management that includes HPE Systems Insight Manager functionality with power management, health check, and deployment tools. It also provides full performance analysis tools for kernel processes and applications. Protect your business’s most critical applications and services to keep your business on target. -
40
Amazon SES
Amazon
Amazon Simple Email Service (SES) is a cost-effective, flexible, and scalable email service that enables developers to send mail from within any application. You can configure Amazon SES quickly to support several email use cases, including transactional, marketing, or mass email communications. Amazon SES's flexible IP deployment and email authentication options help drive higher deliverability and protect sender reputation, while sending analytics measure the impact of each email. With Amazon SES, you can send email securely, globally, and at scale. Using either the Amazon SES console, APIs, or SMTP, you can configure email sending in minutes. Amazon SES also supports email receiving, enabling you to interact with your customers at scale. Regardless of use case or sending volume, you only pay for what you use with Amazon SES.Starting Price: $0.10 per month -
41
SendPulse
SendPulse
A multi-channel marketing automation platform designed to help marketers create personalized promotional campaigns. Users can choose between email, SMS, and web push notification or build an elaborate message sequence by combining several channels in a single campaign. When it comes to email marketing, the platform packs all the necessary tools to automate lead nurturing and lead generation. Users can create custom subscription forms and grow their mailing list. Intuitive drag and drop allows users to design mobile-friendly email templates or choose a predesigned one from a massive gallery. The company, also, offers a transactional email service that users can use to send up to 12000 free emails via SMTP or API. SendPulse has its own chatbot builder. Users can create a Facebook Messenger chatbot or a Telegram chatbot and use it to send personalized campaigns or as an autoresponder.Starting Price: $9 per month -
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Bulk Mailer
Bulk Mailer
Bulk Mailer is the best email marketing software created to design, send and monitor bulk messages. The utility has its own built-in SMTP server that enables it to deliver mass email messages directly to the recipients' mailbox. Bulk Mailer makes it possible to control the effectiveness of your email campaign, it enables you to monitor who, when and where (from what country) opens your email. With mass email software it becomes easy to manage your contacts lists and create personalized HTML messages. This program is indispensable for those who run bulk email campaigns. With its powerful features bulk email software yields spectacular results and beats your business rivals. Bulk Mailer accepts mailing lists generated in Access, Excel, DBF, Word, made in ASCII text files (.txt, .lst). It should be mentioned that it is possible to enter an unlimited number of email addresses. Bulk Mailer provides you with an extremely flexible sending engine. -
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MailerLogic
MailerLogic
MailerLogic is an Enterprise Email Delivery Platform combining ESP-grade infrastructure with real-time deliverability intelligence. It bridges the gap between transactional APIs and bulk sending, ensuring emails land in the inbox, not spam. Key Functionality: 1. Smart Routing: Separates transactional and bulk streams automatically to keep priority mail fast and reputation high. 2. Email Validation: Real-time syntax, domain, and risk checks to reduce hard bounces before sending. 3. Deliverability Tools: Content scoring (spam-risk preview), abuse prevention, and a live 0–100 Health Score for reputation monitoring. 4. Developer-First API: Clean REST endpoints and SMTP relay with SDK examples for Node, Python, and cURL. 5. Webhooks & Analytics: Real-time event notifications (delivered, opened, bounced) and aggregated statistics APIs for external dashboards. 6. Automated Compliance: Built-in suppression list management for unsubscribes and bounces at the transmission layer.Starting Price: $9/month -
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Courier
Double Precision, Inc.
The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework. Individual components can be enabled or disabled at will. The Courier mail server now implements basic web-based calendaring and scheduling services integrated in the webmail module. Advanced groupware calendaring services will follow soon. The Courier mail server's source code should compile on most POSIX-based operating systems based on Linux, and BSD-derived kernels. The Courier mail server should also compile on Solaris and AIX, with some help from Sun's or IBM's freeware add-on tools for their respective operating systems. The Courier mail server evolved out of several related projects, that merged together (more on that later). The Courier mail server implements SMTP extensions for mailing list management.Starting Price: Free -
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turboSMTP
turboSMTP
TurboSMTP understands that email is not just a means of communication but the backbone of your customer engagement strategy. TurboSMTP Email API is trusted by developers and marketers alike for its time-saving features, scalability, and delivery expertise. Our service offers a flexible SMTP relay solution along with advanced features tailored to meet the needs of businesses of all sizes. With our intuitive dashboard, powerful features, and dedicated support, ensuring the delivery of your emails is seamless and uninterrupted. TurboSMTP's infrastructure is built to scale, whether you're sending a few hundred emails or millions. Integration with our service is effortless, with sample code libraries available in multiple languages, interactive documentation, and customizable templates. Monitor engagement data and optimize deliverability with our comprehensive reporting tools. Trust TurboSMTP to deliver your emails reliably and efficiently, empowering you to engage with your audience.Starting Price: $14.95 per month -
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jOfficeConvert
Qoppa Software
Convert Microsoft Word documents and Excel spreadsheets to PDF directly from your Java applications, without user intervention and without the need for any other software. jOfficeConvert is a Java library that can read and render MS Word and Excel documents natively to convert to PDF, to convert to images, or to print the documents automatically. The library is 100% Java so it can run on any platform that supports Java, including Windows, Linux, Unix (AIX, Solaris Spark, Solaris Intel, HP-UX) and Mac OSX. The library does not use any third party software or native calls, it can be run in a server environment or integrated into a desktop application. Main Features Convert Word documents (.doc, .docx) to PDF Convert Excel documents (.xlsx) to PDF Convert Word, Excel to HTML5 (when combined with jPDFWeb) Merge multiple Word, Excel files into a single PDF document Set permissions and passwords on resulting PDF documents. -
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SMTP2GO
SMTP2GO
Send and track all emails easily and securely with SMTP2GO, a reliable outgoing email service solution. SMTP2GO features a redundant, multi data center infrastructure that allows users to send emails even if there is a major internet outage. SMTP2GO has features like real-time analytics, bounce/spam tracking, weekly summaries, spamtrap detection, blacklist monitoring, DKIM/SPF, and more.Starting Price: $10 per month -
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Kingmailer
KingSMTP.com
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.Starting Price: $0 per month -
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Migomail
Migomail
Using an SMTP relay service like Miogmail is the simplest way to get started sending marketing and transactional emails. Send emails as per specific action or send series based bulk email relentlessly. Design creative customize email templates using drag-drop editor or use readymade responsive template. Security is Security is first priority, secure email infrastructure integration with SSL, DKIM, DMARC, SPF, SSL, TLS. Increase your email delivery with advanced management tools and Dedicated IP address. Create professional-looking personalized transactional, promotional and newsletter email. Utilize transactional/promotional SMTP or SMTP API to send bulk email. -
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Instant Bulk SMTP
Instant Bulk SMTP
We understand how important role marketing plays in business and by looking that we have designed our Instant Bulk SMTP service which help to start sending your campaign in less than 30 minutes. Manage multiple contact lists, add, remove, delete, and import-export. Not only can you check bounces, opens, and click-throughs using our email analytics. You can set up or integrate with your applications. Easy to upgrade to a higher plan without any hassle. Instant Bulk SMTP is an outgoing email service that will allow you to send emails from your email address whether you have your own software or you don’t have your own software. We understand how important the role marketing plays in business and by looking at that we have designed our Instant Bulk SMTP service which helps to start sending your campaign instantly. Unlike typical email marketing services, our high-volume SMTP hosting service lets you send from your own application server, email client or a combination of different sources.Starting Price: $50 per month
