Alternatives to Letterbox
Compare Letterbox alternatives for your business or organization using the curated list below. SourceForge ranks the best alternatives to Letterbox in 2026. Compare features, ratings, user reviews, pricing, and more from Letterbox competitors and alternatives in order to make an informed decision for your business.
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1
Proton Mail
Proton AG
Proton Mail is the simplest way to protect your communications with built-in end-to-end encryption. Prevent data breaches, stay compliant with regulations like GDPR and HIPAA, and earn client trust. Protected by Swiss privacy laws and trusted by over 50,000 businesses, Proton Mail keeps your business data confidential and under your control. With Proton Mail and Calendar, your team can securely manage their inbox and schedule, while your organization maintains a professional presence with support for custom email domains and personalized branding. And with the Easy Switch tool, migrating from Google or Microsoft is seamless, no IT expertise required. -
2
CounterMail
CounterMail
CounterMail is a secure and easy to use online email service, designed to provide maximum security and privacy without any unnecessary complexity. You can access your email account at any time, from anywhere in the world. Your account will always be encrypted and anonymous. CounterMail's encryption works automatically and transparently, it requires no specialized computer skills or knowledge. If you are comfortable using services like Hotmail or Gmail, you will be comfortable using CounterMail's secure email! We are using a strong encryption protocol called OpenPGP, with 4096 bits encryption keys to protect your data. To the best of publicly available information, there is no known method which will allow a person or group to break OpenPGP:s encryption by cryptographic or computational means. -
3
SalaX Secure Mail is an easy-to-use and highly secure email encryption solution that can be embedded in your existing email services to protect confidential email communications. Verify all users (senders and recipients alike) with various authentication methods (including strong authentication bank ID, SMS OTP, mail OTP, and password). Ensure security with monitoring features, like audit trails and various reporting options. Protect your communications with end-to-end encryption, all the way from sender to recipient. Secure Mail supports various email security protocols (DMARC, DKIM, SPF) as well as S/MIME-based encryption. You are in control of your data, flexible deployment is possible in the cloud or on-premises. Secure Mail also offers multiple configuration options (APIs, web interfaces). Classify confidential data and adjust security levels according to your policies. Stay compliant with data privacy laws and regulations (e.g. GDPR) thanks to government-grade security.
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4
Mailpile
Mailpile
Mailpile is an effort to reclaim private communication on the Internet. A project to rescue our personal lives from the proprietary cloud and prevent our conversations from being strip-mined for corporate profit and government surveillance. Mailpile is taking e-mail back. Powerful search & tagging makes your pile of mail managable, whether you have just a few messages, thousands or even millions. Mailpile is designed to be fast and responsive, outperforming "the cloud" even on slow computers. And it works even when the Internet is down. OpenPGP signatures and encryption are part of Mailpile's core design, not an afterthought. Mailpile makes it easy to sign and encrypt your mail. It's ironic that most web-mail solutions filter out spam, only to replace it with their own advertisements. Mailpile has no ads. -
5
ZixMail
Zix Corporation
ZixMail is the desktop email encryption solution that provides individuals with a high level of security in their email communications. It's an easy-to-use service that lets users encrypt and decrypt emails and attachments with a single click. Trusted by key figures in Government, Financial, Healthcare, and Legal fields, ZixMail is a unique Email Encryption application that differentiates itself from other solutions by focusing on both the sender and receiver experience. Combining best-in-class encryption technologies with easy to use interfaces, ZixMail is the perfect fit for your organization's email security needs. -
6
Atomic Mail
Atomic Mail
Atomic Mail is a secure and user-centric email hosting provider, dedicated to offering privacy-first email services. With features such as alias creation, robust security measures, and seamless account recovery, AtomicMail ensures your email experience is both private and hassle-free. Creation of Aliases (Hide-my-email): Maintain your privacy by creating multiple email aliases; Spam Free, No Ads; Email Password Protection; End-to-End Encryption: only you and your intended recipient can read the message; Zero Access Encryption: Atomic Mail cannot access your emails; Account Recovery with Seed Phrase: Recover access to your account with a unique seed phrase. Can regain control of your email account without compromising security.Starting Price: $0 -
7
MailHippo
MailHippo
HIPAA compliant email made easy and affordable. MailHippo is the easiest way to securely send and receive sensitive information and attachments by email. There's no setup or configuration required. Just sign up and start sending and receiving HIPAA-compliant emails right away. End-to-end encryption means your sensitive emails and attachments are always secure, both in transit and at rest. MailHippo works with your current email address, and with any email provider. MailHippo looks and works great on any smartphone or tablet. Get a unique link that empowers you to receive totally-secure emails from anyone. Get our HIPAA-compliant email platform with secure encrypted email messaging for FREE during our limited-time Beta program!Starting Price: $4.95 per month -
8
Edison Mail
Edison Software
We spend most of our time in mail, often reading about innovation and productivity. Somewhere along the way, mail got lost. So, we set out to build the best mail experience in the world for mobile. Get organized with categories. The app's assistant will automatically categorize messages for you to make it easier to find. Like peanut butter and jelly, some things go together. Get alerts for flight status changes including delays, cancellations and gate changes. Monitor the price protection window on recent purchases and get notified if the price drops. Get the forecast for my upcoming trips in the assistant to help me pack. Get notified when packages are out for delivery, and view details right in the assistant. Newsletters and mailing lists you don't read and may want to unsubscribe from. Surface directions to the airport for your next flight or your hotel for quick one tap access. -
9
Skiff
Skiff
Skiff is a private, end-to-end encrypted workspace with Mail, Calendar, Pages, and Drive products for completely secure communication and collaboration. All Skiff products are designed with security and privacy in mind. All apps are built with end-to-end encryption (E2EE), so you never have to share your personal information, sensitive data, or private keys with anyone else. At all times, only you can access the content of your emails. Generous free tier - Enjoy 10 GB of free storage for your email, attachments, documents, and notes. - Create up to 4 free email aliases to protect your identity. Open-source and audited - Skiff Mail is open-source, uses open-source cryptography, and undergoes external security audits. - You can access our whitepaper and code at skiff.com. No trackers or ads - Sign up and upgrade without sharing any personal information; use crypto payments in many different currencies to upgrade. - Your data is never collected, sold, or shared. -
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Aspida Mail
Aspida
Aspida Mail was developed with simplicity in mind. We know it's important for you to be able to continue with business as usual. Aspida Mail's setup is seamless and works with any IMAP enabled device. Aspida is HIPAA compliant encrypted email. -
11
gpg4o
Giegerich & Partner
Preserve the privacy of your electronic correspondence. Send confidential email in Microsoft® Outlook® 2010/2013/2016 safely once and for all with gpg4o®, developed by Giegerich & Partner, based on OpenPGP, one of the most widely used and safest cryptographic techniques worldwide. gpg4o® is suitable both for private and enterprise use. gpg4o® by Giegerich & Partner guarantees the privacy of your electronic correspondence by mail encryption. gpg4o® enables the integration of one of the most widely used and safest email encryption systems into Microsoft® Outlook® 2010, Microsoft® Outlook® 2013, Microfost Outlook 2016 and for Microsoft® Outlook® 2019. Easy installation and an intuitive user experience help you preserve the privacy of your email. With the gpg4o® product maintenance, you will always get the latest features for more security and even better user experience.Starting Price: $93 one-time payment -
12
Mailfence
Mailfence
Mailfence is an encrypted email service that offers OpenPGP based end-to-end encryption and digital signatures. Mailfence comes with a plethora of features that boost collaboration without compromising security and convenience. Mailfence documents allow you to safely store and edit documents, you can also share docs with your team with the push of a button. Mailfence calendar will keep your tasks, meetings, and events all in one secure place. Mailfence contacts will store your contacts and it will give you the ability to create mailing lists to maximize efficiency. We designed Mailfence to be a fully interoperable suite, which means you can synchronize Mailfence with most services out there. Mailfence business offers fully customizable whitelabel versions of the Mailfence interface. To put the cherry on top, Mailfence donates 15% of revenues of PRO subscriptions to IFF and EDRI to bolster the fight for Online privacy.Starting Price: $2.50/month/user -
13
Z1 SecureMail Gateway
Zertificon
25% of the 100 German companies with the highest turnover choose Zertificon. Z1 SecureMail Gateway is our highly automated Enterprise Email Encryption solution for effortless, secure communications with anyone, anywhere. Your entire organization encrypts and decrypts, just as well manages & verifies email signatures smoothly in the background. Z1 SecureMail Gateway requires minimal maintenance. And the browser-based admin interface needs no special skills. Keys are managed automatically & central policies enforce security. Integration is fast into your Cloud or On-premises email infrastructure. Your workflows and business are uninterrupted — no employee training needed plus frictionless experience for recipients. With Z1 SecureMail Gateway, encryption is centrally configurable and proofed against human error. You easily achieve and maintain compliance and the highest security standards. You also own all encryption keys and attain German-engineered data sovereignty with no backdoors.Starting Price: from $ 1.50 per user/per month -
14
myMail
My.com
An expert way to manage all email accounts. Your email provider doesn’t support push notifications? With myMail it does. Hate it when an email wakes you at night or distracts you from your barbecue? Choose when you want to receive push notifications. myMail brings profile pictures of your contacts to your message list. Take a look at your inbox to instantly know who’s writing you. myMail displays icons from popular services so that you can recognize the sender in a blink. Your friends don’t use an avatar? We’ll do it for them! For a contact that has no avatar, myMail displays the first letter of the contact’s name. myMail does exactly what it’s meant to do – help you manage your emails – and it does this incredibly well. Traffic compression brings your messages into your mailbox quickly. So you can use your data plan for other things, like watching that cool video. Brings your email in superfast even if the number of messages and contacts you have grows to an amazing size. -
15
Superhuman Mail
Superhuman
Superhuman Mail is an AI-powered email application designed to help professionals manage their inbox faster and more efficiently. The platform focuses on improving productivity by reducing the time users spend reading, writing, and organizing emails. With features like keyboard shortcuts, reminders, and AI-assisted writing, Superhuman helps users respond to important messages quickly and consistently. The app integrates with Gmail and Outlook, allowing teams to upgrade their existing email workflows without switching platforms. Users can schedule emails, snooze messages for later, and receive reminders to follow up on unanswered emails. Built-in read receipts and activity indicators provide insight into when recipients open messages or when teammates are replying. By transforming email into a task-driven workflow, Superhuman Mail helps users stay organized and avoid missed communication.Starting Price: $30 per user per month -
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Amazon WorkMail
Amazon
Amazon WorkMail is a secure, managed business email and calendar service with support for existing desktop and mobile email client applications. Amazon WorkMail gives users the ability to seamlessly access their email, contacts, and calendars using the client application of their choice, including Microsoft Outlook, native iOS and Android email applications, any client application supporting the IMAP protocol, or directly through a web browser. You can integrate Amazon WorkMail with your existing corporate directory, use email journaling to meet compliance requirements, and control both the keys that encrypt your data and the location in which your data is stored. You can also set up interoperability with Microsoft Exchange Server, and programmatically manage users, groups, and resources using the Amazon WorkMail SDK. Amazon WorkMail features simple, low, monthly per-user pricing and costs $4 per user per month which includes 50GB of storage per user.Starting Price: $4 per user month -
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TouchMail
TouchMail
TouchMail is an email app that brings all your accounts into one place with a visual, colorful display that saves you time on your email! TouchMail looks and works great with a touchscreen, or keyboard and mouse. Color code messages by sender. Browse messages at a glance. Less clutter in a few taps. Sort and quickly clean up mail from top senders. The top-rated email app for Windows 10, with over 1.5 million downloads, and one of Microsoft's "Essential Windows 10 Apps". Works great with touch, or quickly scroll and browse with your mouse or touchpad. TouchMail is the fastest and easiest way to find what matters most and clean up the rest in Gmail, Outlook.com, Yahoo Mail, iCloud, AOL, Office 365, and most IMAP email accounts. Turn your email into a visual and colorful inbox that you can explore the way you want – using touch, mouse and keyboard, or pen – with rich visualizations, colorful message tiles you can resize, and familiar interactions.Starting Price: $29.99 one-time payment -
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PBHS SecureMail
PBHS
Achieve and maintain data privacy compliance. PBHS Secure Mail is a mature HIPAA encrypted messaging solution for doctors, dentists, hospitals and other healthcare providers. Compliancy made easy! There is no software to install, configure or maintain. PBHS Secure Mail works on any device, from any location. It’s simple to share. Documents, Radiographs, CT Scans, and Messages are organized and available to all colleagues working on a case. Account initiation is as simple as logging in with your ADA Membership ID. Our optional Outlook Plug-in enables users to send and receive messages directly via Microsoft Outlook on your PC. Treatment Letters and private communications that are delivered from your practice management software to Outlook are now encrypted. Radiographs that are delivered from your digital x-ray systems to Outlook are now encrypted. No need to change how you email your colleagues and patients. Continue to use Outlook without violating HIPAA.Starting Price: $10 per month per account -
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QQmail
Tencent
QQmail app gives you an excellent email experience and instant new mail notifications. You may access your QQ e-mails from an Android device more efficiently. Get new mail notifications instantly, and send photos and files from your phone using QQmail. Preview attachments online or open them with apps on your phone. Search emails in all or specific folders and manage emails easily in the inbox,group-mail folder, personal folders, and other POP account folders. Access emails with enterprise email accounts. Synchronous update data between your phone and computers.Starting Price: Free -
20
K-9 Mail
K-9 Mail
K-9 Mail is designed for both novice and power users and offers lots of features for everyone. K-9 Mail has controllable debug logging. Users can activate logging to help diagnosing problems and errors. As an open source privacy-conscious project we don’t implement an always-on logging system that reports all the device’s activity to a central server. While this would make issues easier to fix it would also be costly to host the server and compromise the privacy of our users. Communication security is an increasingly important subject. K-9 Mail aims to provide intuitive e-mail security in many forms, both in terms of supporting secure login to your e-mail server and in the security of the e-mail itself. -
21
Vivaldi Mail
Vivaldi Technologies
A powerful email client built right into your browser. Vivaldi Mail makes it easy to manage emails from multiple accounts, mailing lists and feeds in a unified inbox. A database of all your messages, labels, filters, searches is maintained by Vivaldi and the bedrock of our powerful email client. Mail from all of your accounts is indexed, so it’s searchable offline. Having a mail client built into your browser just makes sense. Compose messages in new tabs, keep multiple messages open and manage them with ease using Vivaldi’s extensive tab features. There are two counters next to folders in Vivaldi Mail. Brand new mails that have never been seen before are called Unseen. Emails that you have seen but not dealt with are Unread. Use customizable Keyboard Shortcuts to work through email faster. Use the Back/Forward buttons to jump in through “history” and views while you work.Starting Price: Free -
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StartMail
StartMail
StartMail is a secure, private email provider designed to protect your privacy. With StartMail, you can create disposable email addresses anytime, keeping your real inbox safe from spam. We believe privacy is a fundamental human right, and we’ve made it simple for you to protect yours. Even when your recipient doesn’t use encryption, you can still send password-protected messages with just one click. Our service complies with Dutch privacy laws—some of the strictest in the world—and adheres to European privacy standards. For professionals, StartMail also provides the option to secure your own domain with custom email addresses. No software downloads or installations are required; our easy setup gets you up and running in minutes.Starting Price: $35.93 per year -
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Technical Doctor
Technical Doctor
Our HIPAA Compliant E-mail Service lets you Access E-mail, contacts, calendars and files from anywhere, anytime. Increase productivity by collaborating securely with coworkers, customers and suppliers. Save money by not having to purchase licenses, backup or Anti-virus software for your E-mail platform. Maintain data security with hosted E-mail in highly secure data centers with Firewall & Anti-Virus softwares. Mitigate Risk by protecting you against accidental or intentional deletion of E-mails by end usersStarting Price: $25.00 per user per month -
24
Hushmail
Hushmail
Hushmail protects your clients by adding encryption to your emails, web forms and e-signatures. It’s secure, HIPAA-compliant, and trusted by healthcare professionals worldwide. Best of all, Hushmail is easy to set up and use. Send your first encrypted email today, and set up a secure online intake form in minutes. Your Hushmail account works just like a regular email account, with added security features to help keep your data safe. Send and receive encrypted email on the web and iPhone. Access your account using Outlook, Apple Mail or your Android smartphone. Move your forms online in minutes. Hush™ Secure Forms is our secure alternative to old-fashioned paper forms and includes online signing for your most important digital forms. Switching from pen and ink to e-signatures has never been easier.Starting Price: $9.99/month/user -
25
BlueMail
Blix
BlueMail by Blix a free, beautifully designed, universal email app, capable of managing an unlimited number of mail accounts from various providers, allowing for smart push notifications and group emailing while enabling personalization across multiple email accounts. The BlueMail app connects directly to your mail server and is the perfect replacement for your stock email app. With a wide range of visual and technical customizations, swipe actions and menus, action bars and buttons, colors and themes – BlueMail delivers powerful capabilities for your Team. Whether you go Pink or Blue. Go BlueMail. Available on Windows, Mac, Linux, Android, iOS, and Amazon. With the people-centric mailbox, you can focus your attention on emails from only people at the flip of a switch by using People Mode. BlueMail’s navigation picker helps you access any account: IMAP, Exchange or POP3 in a breeze. Each account can be identified by a service provider avatar.Starting Price: $5.99 per user per month -
26
SEPPmail
SEPPmail AG
Sending and receiving digitally signed and encrypted emails is easier and more convenient than ever before. Thanks to the Secure E-Mail Gateway from SEPPmail with integrated and patented GINA procedure for spontaneous encryption, SMEs and large companies secure their entire e-mail communication at the highest level, with the least effort and simplest handling for sender and recipient. With its comprehensive Secure Email solution, SEPPmail is setting new standards for secure, GDPR-compliant email communication. As one of the world’s leading email encryption and signature solutions, SEPPmail includes all the features to protect the sending of confidential data via email, guarantee the authenticity of the sender and ensure the confidentiality and integrity of the message. Thanks to its modularity, the secure e-mail gateway solution can be configured according to customer-specific requirements and expanded seamlessly.Starting Price: 4.5 € per user per month -
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SmarterMail
SmarterTools
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.Starting Price: $500.00/one-time -
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Ciphermail Appliance
in-put
Email encryption with CipherMail Most emails are sent in plain text. This means that anyone who has access to the data stream can read the content of the emails. This is unacceptable for most companies, institutions and organizations and may also violate applicable law. E-mail encryption ensures security and trust in communication. CipherMail is a central mail transfer agent (MTA) that works on the “store and forward” principle. Incoming e-mails, regardless of whether they are from internal or external sources, are only saved until they have been encrypted / decrypted and can be forwarded to the recipient. This happens without changing the email client and is possible in combination with any SMTP server! E-mail encryption can be done using S / MIME, PGP or in a PDF file - in principle or triggered by a trigger in the subject line. CipherMail also includes a Data Leak Prevention (DLP) module.Starting Price: $670 one-time payment -
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Mailspring
Foundry 376
Boost your productivity and send better email with Mailspring, the best mail client for Mac, Linux, and Windows. Multiple accounts (IMAP & Office 365), touch and gesture support, advanced shortcuts, lightning-fast search, undo send, unified inbox, read receipts, link tracking, and more, mac, windows, and linux support, themes and layouts (including dark mode), localized into 9 languages. Mailspring indexes your mail so you can use advanced, Gmail-style search queries and search message contents across all your connected accounts. Never lose an email again. Understand your audience. Send timely follow-up. Turn clicks and opens into actionable insights. Mailspring Pro is your unstoppable email sidekick for sales and business. Mailspring Pro removes the limits in the free version, so you can snooze messages, schedule reminders, and send later an unlimited number of times and conquer your inbox. Understanding your contacts and customers is the key to connecting with them.Starting Price: $8 per month -
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PerfectMail Antispam
PerfectMail
PerfectMail delivers better than 99% filter accuracy with false positives (wanted e-mail blocked as spam) at less than 0.1%. PerfectMail automatically learns about your users and their regular e-mail peers and never blocks their e-mail. The only time PerfectMail might have an issue is with a questionable e-mail from new senders. This takes the risk out of antispam filtering. Most spam filters work like this: receive e-mail, queue, filter, deliver or send a non-delivery reply. The problem with this model is that mail is delayed and senders/recipients may never realize that wanted messages were blocked. PerfectMail works in real-time meaning that it filters messages as they are received - without queuing. This means that PerfectMail tells the sender if their message is being blocked. - PerfectMail's antispam engine is programmed C - the fastest programming language in the world.Starting Price: $499 one-time payment -
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Mail Pilot
Mail Pilot
Mail Pilot is a privacy-first email app designed to help users manage email fatigue and declutter their inboxes. With a clean, focused interface, it allows users to prioritize their most important messages while organizing others into a calm, manageable workflow. Mail Pilot supports all standard IMAP email servers and ensures your emails stay on your device, avoiding third-party servers. The app is native to macOS and offers an intuitive task-based approach to handling emails. Users can sort emails into actionable tasks, schedule messages, and archive emails with ease, all while maintaining an emphasis on privacy and simplicity. The app’s streamlined design has received praise for making email management both efficient and visually appealing. Additionally, Mail Pilot provides a secure environment for managing personal and professional correspondence, ensuring that users can control their inboxes without feeling overwhelmed. -
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RainLoop
RainLoop
Modest system requirements, decent performance, simple installation and upgrade, no database required - all these make RainLoop Webmail a perfect choice for your email solution. Modern user interface. Complete support of IMAP and SMTP protocols including SSL and STARTTLS. Sieve scripts (Filters and vacation message). Minimalistic resources requirements. Direct access to mail server is used (mails are not stored locally on web server). Allows for adding multiple accounts to primary one, simultaneous access to different accounts in different browser tabs is supported. Additional identities. Administrative panel for configuring main options. Really simple installation and update. Integration with Facebook, Google, Twitter and Dropbox. Managing folders list. Simple look'n'feel customization. Configurable multi-level caching system. Extending functionality with plugins installed through admin panel. Perfect rendering of complex HTML mails. Drag'n'drop for mails and attachments.Starting Price: $95 per year -
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Notion Mail
Notion
Notion Mail is an AI-powered email platform that reimagines the inbox with a minimalist, customizable interface designed to streamline communication and enhance productivity. It allows users to organize their inboxes through AI-driven auto-labeling that categorizes emails based on content, such as job offers, travel bookings, or newsletters. Users can create custom "Views" to filter emails by topic, sender, or urgency, enabling focused attention on what's most important. It supports Notion-style slash commands for formatting, built-in scheduling linked with Notion Calendar, and AI-assisted email drafting to expedite responses. Snippets allow for reusable email templates, reducing repetitive writing tasks. Notion Mail maintains robust security standards, including SOC 2 Type 1 certification and HIPAA compliance, ensuring user data is protected.Starting Price: $10 per month -
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Airmail
Airmail
Airmail 3 — This fully accessible mail client was designed specifically for iOS, macOS and watchOS. Email workflow is optimized with extensive customizations, custom actions and deep integration with a wide range of apps and services. Airmail is designed from the ground up to be a powerful mail client which allows you to customize it to meet your needs. Integrate your favorite apps, and create custom actions to make your life easier. Whether you're using your Mac, iPad, iPhone or even your Apple Watch, Airmail can be wherever you need. Add as many email accounts of any type your like to Airmail. (Gmail, GSuite, iCloud Mail, Exchange, Office 365, Microsoft Outlook, IMAP and POP3). See all of the email in all of your inboxes at once with the unified inbox feature. You can even exclude accounts from this view if you want to. When you just want to see the important emails, the smart inbox is here for you.Starting Price: $2.99 per month -
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Clyton
Gammadyne Corporation
Clyton is an email client with advanced security and spam filtering features. The spam filter is highly configurable and supports DNS blacklist checking (DNSBL). Expect 85% of spam to be eliminated with the default configuration. Email that is suspicious but not obviously spam is quarantined for 24 hours and then retested, providing the blacklist enough time to react to new spam sources. The built-in address book supports personalized mass-mailings. Received email cannot run scripts, download multimedia, or use embedded objects without your approval. Other features include encrypted storage, whitelisting, powerful HTML editor, attachment viewer, message drag and drop, custom message templates, SSL encryption, USB flash drive installation, and much more.Starting Price: $29 -
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VirtualPostMail
Virtual Post Solutions
We Scan Your US Postal Mail. You Read It Online. Anytime. Anywhere. Fully Managed Mail Service. VPM is the smartest and easiest way for you to manage your mail and packages so you can focus on what really matters. Permanent Mailbox Address. VirtualPostMail provides you with a street address to receive postal mail. The unopened envelopes are scanned so you can view your mail online at your convenience. Then, you decide whether to have the mail opened and scanned, mail forwarded, or destroyed. Managing your postal mail online is so easy; you’ll never want to handle mail the traditional way again. Check Deposit. Deposit any checks received in your VirtualPostMail account without having to go to the bank. VirtualPostMail Check Deposit Service is a simple and convenient way to deposit checks you receive in your VirtualPostMail account. When you receive a check in your mailbox, you can request to have it deposited into your bank account.Starting Price: $20 per user, per month -
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MailAI
MailAI
MailAI is an AI-powered email-automation platform that deploys personal AI agents that run 24/7 in secure, isolated sandboxes to manage, respond to, and automate workflows in your inbox and calendar. Your agent can auto-respond to customer inquiries, monitor invoices via Stripe, coordinate meeting schedules, generate daily summaries of unread emails, and carry out custom tasks, all triggered by simple plain-English instructions. Built for enterprise-grade data security, MailAI integrates deeply with tools like Gmail, Google Calendar, and Stripe, and supports conversational interaction where you can ask your agent to “find all emails from Sarah about the Q4 deadline” or “schedule a check-in meeting and send the invite.” The system includes powerful features like inbox management, invoice and task tracking, email templates, performance-based workflows, and built-in compliance protections (CASA-verified sandboxes, encryption, GDPR/CCPA support).Starting Price: $25 per month -
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Yahoo! Mail
Yahoo!
Yahoo Mail is a free email service from Yahoo, as well as a mobile app for email management. Thanks for checking out the Yahoo Mail app—the best email app to organize your Gmail, Microsoft Outlook, AOL, AT&T and Yahoo mailboxes. Whether you need a clutter-free mailbox, added customization, different views for deals, receipts, and attachments, or even more storage, we’ve got you covered. -
39
Sylpheed
Sylpheed
Sylpheed is a simple, lightweight but featureful, and easy-to-use e-mail client. Sylpheed provides intuitive user-interface. Sylpheed is also designed for keyboard-oriented operation, so Sylpheed can be widely used from beginners to power users. Sylpheed runs on many systems such as Windows, Linux, BSD, Mac OS X and other Unix-like systems. Sylpheed uses GTK+ GUI toolkit. The newest version of Sylpheed works with GTK+ 2.4 or later (2.6 or later is recommended). Sylpheed is a free software distributed under the GNU GPL (the library part is GNU LGPL). You can freely use, modify and redistribute it under the license. Sylpheed adopts 3-paned display similar to the popular e-mail clients for Windows such as Outlook Express and Becky. So it is easier to use it on the first time. The user-interface is constantly improved, and Sylpheed achieves attentive, comfortable operationality. -
40
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 -
41
Claws Mail
The Claws Mail Team
Claws Mail is an email client (and news reader), based on GTK+, featuring quick response, graceful, and sophisticated interface, easy configuration, intuitive operation, abundant features, extensibility and robustness and stability. The appearance and interface are designed to be familiar to new users coming from other popular email clients, as well as experienced users. Almost all commands are accessible with the keyboard. The messages are managed in the standard MH format, which features fast access and data security. You'll be able to import your emails from almost any other email client, and export them just as easily. Lots of extra functionality, like an RSS aggregator, calendar, or laptop LED handling, are provided by extra plugins. Claws Mail is distributed under the GPL. -
42
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. -
43
ProDMARC
PROGIST
Attackers use spoofed emails to phish your customer’s & employee’s credentials. Hackers send forged invoices through mails to your partners & suppliers. Attackers send malicious mails containing malware like Ransomware. Attackers sell illegal goods like weapons or drugs using mail by spoofing trusted brands. DMARC is an email validation protocol built on 2 globally accepted authentication protocols namely SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). SPF is an email authentication protocol that allows the receiving mail server to check if the sender mail server is authorized to send emails on behalf of the organization. DKIM is a public and private cryptography based authentication protocol designed to ensure that messages aren’t altered in transit between the sender & receiver mail server.Starting Price: $100 per year -
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500Mail by 500apps
500apps
500Mail is an email client software by 500apps that provides secure, encrypted, and ad-free emails service used by small enterprises for accessing emails reliably and world-class data security. The main USP's of 500Mail include providing world-class data security, accessing any device, and providing unlimited mailboxes. 500Mail has an added feature to add multiple domains in a single interface and facilitate access to unlimited mailboxes for particular domains. With 500Mail filters, users can organize their inbox by applying conditions and actions for the incoming and outgoing emails. Signatures at the end of the emails are added to promote your business.Starting Price: $14.99 per month -
45
Lavabit
Lavabit
Secure email for the world. Because everyone has the right to communicate privately. Flow is the most secure email solution for traditional email—compatible with most email clients. Volcano—our free, open source mail client—takes full advantage of the Dark Internet Mail Environment. Magma is our open source server for the Dark Internet Mail Environment—perfect if you need to host your own secure email. We're pioneers in encrypted email who believe all people have the right to private and secure communication. By establishing secure, end-to-end encryption standards and technologies, we're revolutionizing how the world communicates and protects its digital privacy. -
46
HCL Notes
HCL Software
Integrate social collaboration, messaging and business applications into a single workspace. HCL Notes is the email client software that gives teams access to email, calendar, and contact management capabilities, and seamlessly integrates other collaboration tools and HCL Domino business applications. With an improved user experience and enhancement of essential mail features, HCL Notes transforms your everyday email into an operational center and becomes even more essential to how your team’s work. Integrate social collaboration, messaging and business applications into a single workspace with Notes. Now, with an improved user experience and enhancement of essential mail features. From leading logistics companies to powerful banks and fashion houses, thousands of the smartest businesses in the world rely on Notes to help run their everyday. -
47
Proton Calendar
Proton AG
Your calendar is a record of your life. Proton Calendar helps keep it private. Proton Calendar automatically secures all your events with end-to-end encryption. Events received from people who use other calendars are secured with zero-knowledge encryption. In both cases, event details, including the title, description, location, and people invited, are encrypted so not even we can see them. Proton Calendar makes staying on top of your schedule simple while keeping your information secure. Proton Calendar was built by the team behind Proton Mail, the world’s largest encrypted email service. Over 50 million people and some of the world’s largest organizations have signed up with Proton. Proton Calendar comes with a Proton Mail email address that you can use to securely send event invites. You can also add events to Proton Calendar directly from your Proton Mail inbox.Starting Price: Free -
48
Escapees Mail Forwarding
Escapees RV Club
Escapees RV Club operates the country’s oldest, largest and most economical private mail forwarding service. Since 1985, our Mail Forwarding Service, a commercial mail-receiving agent licensed by the U.S. Postal Service, has enabled full-time and part-time RVers to receive their mail and packages wherever they travel in North America, whenever they want, and always with our friendly, personal attention. You'll have a unique mailing address in Texas, South Dakota or Florida, usable as your legal domicile. We can forward your mail to you wherever your RV takes you, on request or on a schedule you specify. Our in-house staff will review your mail with you by phone. An optional service that lets you view your received First Class envelopes and mail contents online. Choose to receive only certain types of mail, or specify only particular senders or items to forward. Set forwarding instructions, view your postage balance, and more from your mail service dashboard.Starting Price: $95 per year -
49
Mailtrim
Mailtrim
Reinventing email to live in your inbox! A powerful standout mail tool to send and receive organised email communications. Sync all your emails Manage all your emails and contacts from multiple accounts easily in one unified inbox. Best free email client. Highly customisation. Give a new look to your email with the finest outlook alternative, the mailtrim. Choose from a ton of customizations to send a unique type of business email. Best free email client. Secure and private. Have round-the-clock control on the emails you send and receive! Acquire this secure email client and apply pgp encryption to hide the contents of your emails. Sophisticated and slick UI. Have high user-experience with a minimally designed interface. Find everything fast! Have this best free email client for personal and professional use that has an easy-to-navigate immersive user interface. The quick to use email client for windows and mac allows the users to send smart emails.Starting Price: Free -
50
Aussie Mailman
Aussie Mailman
Australia’s premier virtual address, mail forwarding and redirection service. Aussie Mailman provides the means so you can stay regularly and securely in contact with all your mail correspondence for home or work from anywhere in Australia or the world, so that you can manage your affairs. Aussie Mailman dispatch via Australia Post or upload your mail for you every business day of the year, except on NSW public holidays. We even have plans with your permission that allow us to open your mail and scan the contents of your mail so you can read your mail anywhere at any time. So for better or for worse, wherever and whenever you travel, you need your mail. Aussie Mailman is an Australian mail scanning service and mail redirection business operating since 2010 based in Sydney, New South Wales. We offer the ideal mail scanning and forwarding service anywhere to keep you up to date with all your mail correspondence whether you are in Australia or elsewhere in the World.Starting Price: $15 per month