Best Email Clients in 2026: Desktop, Mobile, Open-Source and Keyboard-First Apps

The best email client depends on where you read mail. Thunderbird is the best free, open-source choice for the desktop, eM Client suits people replacing Outlook on Windows or Mac, and Superhuman and Spark focus on speed and AI triage. On Android, Thunderbird for Android and FairEmail are the open-source picks.

This guide is about apps, not providers. A client is the program you read mail in, while a provider such as Gmail stores your mailbox, and if you want to change that, read the Gmail alternatives guide instead. The picks are grouped by job: open-source desktop, Windows and Mac, speed and AI, Android, and teams.

Email clients, providers and webmail: what is the difference?

Three things get mixed up. A provider runs your mailbox and has your address, for example Gmail, Fastmail, Proton Mail or Outlook.com. A client is the app that connects to it, on a computer or phone. Webmail is a client that runs in a browser, usually the one your provider supplies.

Most clients connect to many providers through standard protocols, so you can switch client without changing address. Some providers restrict this: Proton Mail, for example, needs its separate Bridge add-on before a desktop email client can read your mailbox, and some clients are built for one provider only, such as Mimestream for Gmail. Microsoft Outlook and Apple Mail blur the line because the names cover both a service and an app, covered below.

How we picked

Each app has to read and send mail from at least one standard mailbox on a computer or phone. Enlisted's data decided the rest: platforms, free plan or trial, licence and recent GitHub activity for open-source projects, and the vendor's own description of features. Facts come from Enlisted's listings and each vendor's site, and privacy statements are the vendors' claims, not our own findings. Prices change, so the live pricing section after this guide is the place to check them. The ranking method behind every Enlisted guide is written up in full.

Best free open-source desktop email clients

1. Thunderbird: best free, open-source desktop email client

Thunderbird is a free, open-source email application from the Mozilla family, built on the same platform as Firefox. Its site lists versions for Windows, macOS, Linux and Android, a unified inbox for managing several accounts, calendar and contacts integration, tags for organizing mail and add-ons for extending it. It is funded by user donations, and its site says it does not collect personal data, sell ads in your inbox or train AI on your private conversations.

Enlisted's listing tracks the source-tree repository on GitHub, a copy of Mozilla's comm-central tree. If you want a more tuned build, Betterbird, which is not in Enlisted's catalogue, describes itself as a fine-tuned version of Thunderbird with extras such as a multi-line view, vertical tabs and account colors, for Windows, Linux and macOS.

• Best for: anyone who wants a free, customizable desktop client that works with many providers.
• Watch out for: its site lists Windows, macOS, Linux and Android but not iOS, so iPhone users need another app. It is more customizable than minimal, so expect some setup.

2. Mailspring: best open-source desktop client with a local sync engine

Mailspring is an open-source desktop email client for Mac, Windows and Linux that keeps its sync engine on your computer. The interface is written with Electron and React and the C++ sync engine runs locally, and the README says email credentials are not sent to the cloud. Its site says it works with Gmail, iCloud, Office 365, FastMail, Outlook.com, Yahoo and any IMAP or SMTP account.

The free version covers multiple accounts, a unified inbox and search, according to Mailspring's site, and a Pro tier adds extras such as read receipts, link tracking and send later. Enlisted lists the licence as GPL-3.0, while Mailspring's own site mentions the MIT licence, so check the repository's licence file if that matters to you.

• Best for: people who want an open-source desktop client for Mac, Windows or Linux with a plugin architecture, mail rules and templates.
• Watch out for: some of the features people want, such as send later and templates, sit in the paid Pro tier, per its site.

Best desktop email clients for Windows and Mac

3. eM Client: best Outlook replacement on Windows and Mac

eM Client is a desktop email client for Windows and macOS, with companion apps for Android and iOS, that puts email, calendar, contacts, tasks, notes and chat in one program. The vendor presents it as a replacement for Microsoft Outlook or Mozilla Thunderbird. Its site lists support for Google Workspace, Office 365, Outlook, Exchange and general IMAP and POP accounts.

It includes inbox categories, quick actions, PGP message encryption, translation and snooze, plus an optional AI add-on that is sold with extra credits. Its site lists a free version for home users, and Enlisted lists paid personal and business licences with a trial. See the eM Client page.

• Best for: people leaving Outlook who want a similar all-in-one client on Windows or Mac.
• Watch out for: it is closed source with no Linux version listed, and the free licence limits the number of accounts.

4. Microsoft Outlook: best if your work runs on Microsoft 365

Microsoft Outlook is Microsoft's email, calendar and contacts application for personal accounts at outlook.live.com and for work or school accounts, with web, desktop and mobile access. Enlisted lists a free plan, and the name covers both a mail service and an app, so the one you use depends on the account you sign in with.

It is the default in many offices because it pairs with Microsoft's calendar and meeting tools. Details on current plans and which apps are included are on Microsoft's site. If you are weighing alternatives, see Outlook alternatives.

• Best for: people and companies already using Microsoft 365 for calendars, meetings and files.
• Watch out for: it is proprietary and tied to Microsoft's ecosystem, so look at eM Client or Thunderbird if you want something vendor-neutral.

5. Apple Mail: best built-in client for Apple devices

Apple Mail is the email client included with Apple's operating systems that manages iCloud, Gmail, Outlook and other IMAP accounts in one app. Because it ships with the system, there is nothing to buy or install.

Recent versions add blocking of messages from specific senders or groups and automatic sorting of incoming mail into Primary, Transactions, Updates and Promotions. On supported devices and languages, Apple Intelligence Writing Tools can summarize text, proofread a draft and suggest wording. Apple publishes a Mail User Guide for each macOS version. See Apple Mail alternatives.

• Best for: iPhone, iPad and Mac users who want a free, no-setup client for several accounts.
• Watch out for: it is proprietary and tied to Apple devices, so it is not an option on Windows or Linux.

6. Mimestream: best native Mac client for Gmail

Mimestream is a native macOS email client that connects through the Gmail API rather than IMAP, which the developer says gives a faster experience and access to Gmail-specific features. It supports Gmail inbox categories, colored labels, server-side filters, Gmail-powered search, snooze, vacation responses and replying to calendar invitations, and it blocks trackers from common services.

It is a paid subscription with a free trial and no one-time purchase, according to Enlisted's data. If Gmail is your mailbox and your computer is a Mac, it is built for exactly that combination. See the Mimestream listing.

• Best for: Mac users who stay on Gmail and want a fast native app.
• Watch out for: it is built around the Gmail API on macOS, so it is not for other platforms, and it is closed source with a subscription.

Best email clients for speed, shortcuts and AI triage

7. Superhuman: best keyboard-first client for clearing a busy inbox

Superhuman is an email client built around keyboard shortcuts, AI drafting and send-later scheduling that now belongs to a wider AI productivity suite. The company lists Mail, Calendar, Docs, Databases and agents, and describes its mail product as one that surfaces important messages and filters out distractions automatically.

Enlisted lists a free plan and paid per-member plans, with Enterprise quoted. Enlisted's entry does not list supported mail providers or platforms, so confirm which accounts it works with on Superhuman's site before you commit. See Superhuman alternatives.

• Best for: people who process large volumes of email and want speed from the keyboard.
• Watch out for: it is a proprietary, subscription product moving toward a broader AI suite, so check which mail features your plan includes.

8. Spark Mail: best for a smart inbox and shared team inboxes

Spark Mail is a commercial email client that aims to cut the noise in a busy inbox with a smart inbox that puts priority contacts first and files newsletters and notifications into their own inboxes. Its tools include Done and Set Aside markers, send later, snooze, follow-up reminders and a Gatekeeper that screens new senders. An AI assistant can search and summarize mail, and an AI writing assistant drafts replies.

Its site lists apps for Mac, iPhone, iPad and Windows, and says it works with IMAP, iCloud, Exchange, Outlook, Yahoo and Google accounts. Teams can share inboxes and discuss messages in private comments. Enlisted lists a free plan and a trial of the paid tiers. See Spark alternatives.

• Best for: professionals on Apple devices and small teams that want to share and delegate email.
• Watch out for: check which features the free plan includes, and note it is closed source.

9. Shortwave: best AI-heavy client built on Gmail

Shortwave is a commercial email client built on Gmail that adds an AI agent for organizing mail, writing replies, searching and scheduling meetings from plain-language prompts. It also offers AI filters written in plain English, a split inbox that divides mail into tabs and integrations with tools such as Slack, Notion, Asana and HubSpot.

Enlisted lists no free plan, and a trial. It is aimed at people who live in Gmail and want AI to do triage. See Shortwave alternatives.

• Best for: Gmail users and teams that want an AI assistant working across their mail.
• Watch out for: it requires a Gmail-based account, it is paid with no free plan, and it is AI-first, which some people would rather avoid.

10. Canary Mail: best for AI features with PGP and a free tier

Canary Mail is a cross-platform email client for Mac, iOS, Android and Windows that pulls several accounts into one inbox. Its AI features draft emails in your voice, summarize long threads and categorize incoming mail, and it adds read receipts, one-click unsubscribe, snooze and templates, plus an integrated calendar.

On security, it supports PGP end-to-end encryption and a SecureSend option aimed at HIPAA needs, as the vendor describes it. Enlisted lists a free plan and a trial, with paid tiers billed yearly or as one-time lifetime plans and no monthly billing. See the Canary Mail page.

• Best for: people who want AI features and PGP in one multi-platform client.
• Watch out for: it is closed source, the security claims are the vendor's own, and paid plans are yearly or lifetime.

Best cross-platform email client, including Linux

11. BlueMail: best free cross-platform client with a Linux version

BlueMail is a cross-platform email client for iOS, Android, macOS, Windows and Linux that consolidates accounts into a unified inbox. It offers instant push, groups mail by people and clusters, and includes a calendar, an optional team messaging product and an AI assistant called GemAI that drafts, translates and summarizes.

It advertises PGP and S/MIME encryption, tracker blocking and a zero-knowledge philosophy, which are vendor claims. Enlisted lists a free Personal plan, and paid Plus and Team plans with trials. See the BlueMail entry.

• Best for: people who want one client on Linux, desktop and phone with a free tier.
• Watch out for: it is closed source, and the privacy claims are the vendor's, so read its security pages.

Best email clients for Android

12. Thunderbird for Android: best open-source Android email app

Thunderbird for Android is an open-source email app for Android that manages multiple accounts with an optional unified inbox. It is the Android edition of Thunderbird and is based on K-9 Mail, which was the project's earlier name, and it is written in Kotlin. The project says Thunderbird never treats private data as a product.

It is released under Apache-2.0 and can be installed from Google Play, F-Droid, GitHub releases and other routes, in stable or beta channels. Pair it with Thunderbird on the desktop for a matching setup. See the Thunderbird for Android page.

• Best for: Android users who want an open-source, free app from the Thunderbird project.
• Watch out for: it is Android only, and it is a client, so you bring your own mailbox.

13. FairEmail: best privacy-focused minimal client for Android

FairEmail is an open-source email app for Android designed around privacy and a deliberately minimal interface. It is an email client only, so you bring your own address, and it works with virtually all providers using IMAP, POP3 and SMTP, including Gmail, Outlook and Yahoo.

It supports unlimited accounts, a unified inbox, conversation threading, push notifications and offline use. Privacy features include OpenPGP and S/MIME encryption, a safe message view that strips unsafe HTML and scripting, tracking-image detection and confirmation before opening links. It is released under GPL-3.0. See the FairEmail listing.

• Best for: privacy-minded Android users who want fine control over how mail is displayed.
• Watch out for: it is Android only, and a minimal interface suits people who prefer control over polish.

Best email client for teams sharing an inbox

14. Missive: best collaborative inbox for team email

Missive is a collaborative inbox that brings team email, chat and shared drafts into one app, built for teams that do most of their work over email. Colleagues can see who is dealing with a conversation without forwarding messages around, and several people can edit one draft. It also turns emails into trackable work and pulls context from other tools, with an AI assistant and apps for desktop and mobile.

Enlisted lists no free plan and a 30-day trial, with per-user paid plans. Its pages describe use cases such as support, accounting, law, real estate and logistics. See the Missive page.

• Best for: support, accounting and law teams that share mailboxes and need delegation.
• Watch out for: it is built for teams and priced per user, so it is more than a solo user needs.

Webmail and other clients worth knowing

Roundcube is an open-source, browser-based IMAP client with an address book, folder management and a plugin API, which people often put in front of a self-hosted mail server; see the Gmail alternatives guide for those servers. Mailbird is a Windows client that merges several accounts and connected apps into one inbox. Mailpile is a web-based client with PGP-focused encryption, but Enlisted notes development of the original version has halted pending a rewrite. For hosted providers, Fastmail, Proton Mail and HEY each publish their own apps.

How to choose the best email client

Start with your device, then your mailbox, then how much you want to pay.

Check two things before you switch. First, confirm your provider supports standard connections or has its own app, because some providers limit third-party clients. Second, note that AI features, tracking features and sync options vary between free and paid tiers. If you are also reconsidering your provider, read the Gmail alternatives guide, and browse the email category for more tools. For related picks on getting through your day, see the best productivity apps guide.