An email client is a software application that lets you send, receive, read, and organize email messages. Email clients come in two main forms: desktop apps installed on your computer and webmail clients accessed through a browser. Most modern options offer both, plus mobile apps.

The right email client can make you faster, more organized, and less stressed about your inbox. The wrong one can waste hours of your week. This guide covers the 12 best options for Windows and Mac across free and paid categories.

Table of Contents

• • Key Insight
• Key Terms
• The 10 Factors That Make a Great Email Client
• The Best Free Email Clients
  • 1. Gmail
    • Quick Summary
    • Who Should Choose Gmail
  • 2. Canary Mail
    • Quick Summary
    • Who Should Choose Canary Mail
  • 3. Mozilla Thunderbird
    • Quick Summary
    • Who Should Choose Thunderbird
  • 4. Mailbird
    • Quick Summary
    • Who Should Choose Mailbird
  • 5. Edison Mail
    • Quick Summary
    • Who Should Choose Edison Mail
  • 6. eM Client
    • Quick Summary
    • Who Should Choose eM Client
  • 7. Mailspring
    • Quick Summary
    • Who Should Choose Mailspring
  • 8. Proton Mail
    • Quick Summary
    • Who Should Choose Proton Mail
    • Pro Tip
• The Best Paid Email Clients
  • 9. Outlook
    • Quick Summary
    • Who Should Choose Outlook
  • 10. Superhuman
    • Quick Summary
    • Who Should Choose Superhuman
  • 11. Front
    • Quick Summary
    • Who Should Choose Front
  • 12. Spike
    • Quick Summary
    • Who Should Choose Spike
• Comparison Table
• Getting Email Analytics From Your Email Client
• Start Here: Your Email Client Checklist
• Frequently Asked Questions
  • What is an email client?
  • What is the best free email client?
  • Is Outlook free?
  • Is Superhuman worth the price?
  • What is the most secure email client?
  • Can I use multiple email accounts in one client?
  • What email client works best for teams?

Key Insight

The email client landscape shifted in 2025 with Grammarly’s acquisition of Superhuman for approximately $825 million. AI-powered features like auto-drafts, smart categorization, and AI writing assistants are now standard expectations, not premium extras. Even free clients like Gmail and Thunderbird have added AI capabilities.

Key Terms

Email Client: Software that lets you send, receive, read, and organize email. Can be a desktop application (Outlook, Thunderbird), a web interface (Gmail), or both.

Webmail: An email client accessed through a web browser with no software installation required. Gmail and Outlook.com are the most popular webmail services.

IMAP (Internet Message Access Protocol): A protocol that syncs email between a server and multiple devices. Changes you make on one device (like reading or deleting) appear on all others.

POP3 (Post Office Protocol 3): An older email protocol that downloads messages to a single device and typically removes them from the server. Less common today because it doesn’t sync across devices.

End-to-End Encryption: A security method where only the sender and recipient can read the email content. Even the email provider can’t access the message. Proton Mail uses this by default.

Unified Inbox: A feature that combines messages from multiple email accounts into a single view. Useful for people managing personal, work, and other accounts simultaneously.

The 10 Factors That Make a Great Email Client

We evaluated every client on this list against 10 criteria. Here’s what matters most when choosing an email client.

1. Desktop vs. webmail. Some clients are desktop-only, some are web-only, and some offer both. Consider where you work most and whether offline access matters to you.

2. Mobile app quality. Most people check email on their phones. A poorly designed mobile app can negate every advantage of a great desktop experience.

3. Organization systems. Outlook uses folders. Gmail uses labels. Superhuman uses Split Inbox. The system matters less than whether it matches how you think. For a comparison, see Outlook vs. Gmail.

4. Storage and attachment limits. Free clients typically cap storage at 1-15 GB. Paid plans expand limits significantly. Attachment size limits (usually 25 MB) apply almost everywhere.

5. Built-in tools. Calendar integration, email scheduling, snooze, reminders, and undo send are now table stakes. Check which tools come standard and which require upgrades.

6. Collaboration features. Shared inboxes, internal comments, and account consolidation matter for teams. Front and Hiver specialize in this. Solo users can skip it.

7. Add-on and extension support. Gmail and Thunderbird have extensive add-on ecosystems. Superhuman and Spike are more self-contained. If you rely on third-party tools, check compatibility first.

8. Customization options. Some users want to change themes, layouts, and notification behavior. Others want defaults that just work. Mailbird and eM Client offer deep customization.

9. Number of users supported. Some free clients limit you to one user or one account. Team-oriented clients like Front scale to hundreds of seats.

10. Cost. Prices range from free to $40/month per user. The most expensive client isn’t always the best fit. Match the price to the features you’ll actually use.

The Best Free Email Clients

These email clients are either completely free or offer robust free versions. For most individual users, one of these will be more than enough.

1. Gmail

Quick Summary

Gmail is the world’s most popular email client, offering powerful search, label-based organization, and seamless integration with Google Workspace. It’s free for personal use with 15 GB of shared storage.

Gmail handles over 1.8 billion active accounts and sets the standard that other email clients measure against. Its search is best-in-class, labels provide flexible organization, and the mobile apps for iOS and Android are polished and fast.

Gmail’s third-party add-on ecosystem is extensive. You can customize it with tools for email tracking, scheduling, CRM integration, and more. Google’s Gemini AI is also now integrated directly into the compose window.

Pricing: Free for personal use (15 GB shared storage). Google Workspace Business Starter at $7/user/month.

Key Features:

• Industry-leading search across all emails and attachments
• Label-based organization with smart categories and filters
• Gemini AI integration for drafting, summarizing, and organizing
• Massive third-party add-on marketplace
• Polished mobile apps for iOS and Android

Who Should Choose Gmail

• Individual users who want a reliable, free email client with powerful search
• Teams already using Google Workspace for docs, sheets, and calendar
• Anyone who wants access to the largest ecosystem of email add-ons

2. Canary Mail

Quick Summary

Canary Mail is a privacy-focused email client with built-in end-to-end encryption and an AI Copilot for composing emails. It works across Windows, Mac, iOS, and Android.

Canary Mail’s AI Copilot helps you write, summarize, and prioritize emails directly in the app. The interface is clean and modern, with cross-platform sync keeping your inbox consistent across all devices.

Built-in encryption sets it apart from most competitors. You get PGP encryption without needing to configure anything manually.

Pricing: Free (basic features). Pro at approximately $20/year for individuals. Teams pricing available.

Key Features:

• AI Copilot for email writing, summarization, and prioritization
• Built-in PGP end-to-end encryption without manual setup
• Cross-platform sync across Windows, Mac, iOS, and Android
• Focused inbox that filters out newsletters and promotions
• Read receipts and email tracking

Who Should Choose Canary Mail

• Privacy-conscious users who want encryption without complexity
• Professionals who want AI writing assistance built into their email client
• Users who work across multiple devices and need consistent sync

3. Mozilla Thunderbird

Quick Summary

Mozilla Thunderbird is a free, open-source desktop email client with support for multiple accounts, add-ons, and deep customization. It’s a common choice for startups and small businesses.

Thunderbird is completely free with no paid tiers or hidden upgrades. It supports IMAP and POP3 for virtually any email provider, and its add-on library lets you extend functionality in dozens of directions.

The Thunderbird team shipped a major interface redesign (Supernova) that modernized the look without sacrificing the flexibility power users love.

Pricing: Free. Open source.

Key Features:

• Completely free with no paid tiers or feature restrictions
• Supports multiple accounts via IMAP, POP3, and Exchange
• Extensive add-on library for customization
• Built-in calendar, task manager, and RSS reader
• Open source with active community development

Who Should Choose Thunderbird

• Users who want a fully free, open-source desktop email client
• Startups and small businesses that need multi-account support at zero cost
• Power users who want deep customization through add-ons

4. Mailbird

Quick Summary

Mailbird is a Windows and Mac email client designed for managing multiple accounts in a unified inbox. It connects with a wide range of third-party apps and offers a one-time purchase option.

Mailbird’s unified inbox pulls messages from all your email accounts into a single view. The interface is clean and customizable with themes, layouts, and notification settings.

Third-party integrations include Slack, Trello, Google Calendar, WhatsApp, and more, making it a productivity hub beyond just email.

Pricing: One-time payment of $39.50, or $19.50/user/year. Free trial available.

Key Features:

• Unified inbox for managing multiple email accounts
• Highly customizable themes, layouts, and notifications
• Integrations with Slack, Trello, Google Calendar, and more
• Email tracking, snooze, and send-later functionality
• One-time purchase option (no recurring subscription)

Who Should Choose Mailbird

• Users managing multiple email accounts who want a unified view
• People who prefer a one-time purchase over monthly subscriptions
• Windows and Mac users who want deep third-party app integrations

5. Edison Mail

Quick Summary

Edison Mail is a completely free email client that never serves ads. It’s designed for mobile-first use with automatic email sorting, package tracking, and sender verification.

Edison Mail’s biggest selling point is its ad-free experience. Unlike Gmail, you’ll never see ads in your inbox. The app automatically categorizes emails into useful groups like package tracking, flight notifications, and subscription management.

One-tap unsubscribe and sender verification features help you keep a clean, safe inbox.

Pricing: Free. No paid tiers.

Key Features:

• Completely ad-free email experience
• Automatic sorting into categories (packages, flights, subscriptions)
• One-tap unsubscribe from mailing lists
• Sender verification to help avoid email scams
• Mobile-first design with a polished smartphone interface

Who Should Choose Edison Mail

• Users frustrated by ads in Gmail who want an ad-free alternative
• Mobile-first email users who primarily check email on their phone
• Anyone who wants automatic email categorization and easy unsubscribing

6. eM Client

Quick Summary

eM Client is a feature-rich desktop email client available in over 20 languages. It includes built-in encryption, an attachment manager, and calendar/scheduling tools. Free for up to 2 email accounts.

eM Client offers a polished desktop experience for Windows and Mac with features you’d expect from paid clients. Built-in PGP encryption, a smart attachment manager, and contact management come standard.

The free version supports up to 2 email accounts, which is enough for many individual users. The Pro version removes that limit and adds commercial use rights.

Pricing: Free (up to 2 accounts). Pro at $49.95/device (one-time). Pro upgrade subscription also available.

Key Features:

• Built-in PGP encryption for secure email
• Smart attachment manager for easy file handling
• Calendar, tasks, and contacts integrated in one app
• Available in over 20 languages
• Free for up to 2 email accounts

Who Should Choose eM Client

• Users who want a feature-rich desktop client without a subscription
• International teams that need support in 20+ languages
• Individuals managing 1-2 accounts who want a capable free option

7. Mailspring

Quick Summary

Mailspring is a cross-platform email client with a unified inbox, built-in translation, automatic reminders, and email snooze. The free version covers core features; Pro adds tracking and analytics.

Mailspring’s free tier includes multiple account integration, email snooze, and RSVP tools. The Pro version adds read receipts, link tracking, and send-later scheduling for just $8/month.

It supports over 60 languages and runs on Windows, Mac, and Linux, making it one of the most broadly compatible clients on this list.

Pricing: Free (core features). Pro at $8/month.

Key Features:

• Unified inbox for multiple email accounts
• Built-in translation supporting 60+ languages
• Email snooze, reminders, and RSVP tools
• Read receipts and link tracking (Pro)
• Cross-platform support: Windows, Mac, and Linux

Who Should Choose Mailspring

• Users who need cross-platform support including Linux
• Professionals who want email tracking at an affordable price
• Multilingual users who benefit from built-in translation

8. Proton Mail

Quick Summary

Proton Mail is a privacy-first email client with end-to-end encryption, created by Swiss scientists who met at CERN. It stores no IP logs and lets you create accounts with no personal information.

Proton Mail encrypts every message end-to-end by default. Even Proton’s own servers can’t read your email content. The service is based in Switzerland under some of the world’s strongest privacy laws.

The free plan provides 1 GB of storage and up to 150 messages per day. Paid plans expand storage, add custom domains, and include Proton’s VPN, calendar, and cloud drive services.

Pricing: Free (1 GB, 150 messages/day). Mail Plus at approximately $5/month. Proton Unlimited at approximately $10/month. Business from $6.99/user/month. All billed annually.

Key Features:

• End-to-end encryption on all messages by default
• Zero IP logging and Swiss privacy law protection
• Self-destructing messages with expiration timers
• Open source with independently audited security
• Bundled VPN, calendar, and cloud drive on paid plans

Who Should Choose Proton Mail

• Privacy-conscious individuals who want encrypted email by default
• Journalists, activists, and professionals handling sensitive information
• Organizations that need Swiss-based data hosting for compliance reasons

Pro Tip

If you’re using Gmail with a team, pair it with EmailAnalytics to track email response times, volume, and activity patterns across all agents. The email client handles delivery; EmailAnalytics handles the performance data you need to improve.

The Best Paid Email Clients

These clients require a paid subscription for full functionality. Each one offers capabilities that go beyond what free clients provide, whether that’s raw speed, team collaboration, or CRM features.

9. Outlook

Quick Summary

Outlook is Microsoft’s email client with a traditional folder-based organization system, deep integration with Microsoft 365 apps, and a built-in calendar. A free web version is available.

Outlook is the default email client for millions of businesses running Microsoft 365. Its folder-based organization feels familiar to long-time email users, and its calendar integration is among the best available.

The new Outlook app (which replaced the classic desktop version) unifies the experience across web, desktop, and mobile with Microsoft’s Copilot AI built in for drafting and summarizing.

Pricing: Free (web version). Microsoft 365 Personal at $69.99/year. Microsoft 365 Business Basic at $6/user/month.

Key Features:

• Deep integration with Microsoft 365 (Word, Excel, Teams, OneDrive)
• Folder-based organization with rules and focused inbox
• Built-in calendar with scheduling assistant
• Microsoft Copilot AI for drafting and summarizing
• Available on Windows, Mac, web, iOS, and Android

Who Should Choose Outlook

• Organizations already invested in the Microsoft 365 ecosystem
• Users who prefer traditional folder-based email organization
• Teams that need tight calendar and scheduling integration

10. Superhuman

Quick Summary

Superhuman is the fastest email client available, built for Gmail and Outlook users who process high volumes of email daily. Acquired by Grammarly in October 2025 for approximately $825 million.

Superhuman’s core promise is speed. Over 100 keyboard shortcuts let you triage email without touching a mouse, and emails render in under 100 milliseconds. Users report getting through email twice as fast and saving over 4 hours per week.

The October 2025 AI update added Auto Drafts (AI writes follow-up emails in your voice), Auto Labels (automatic categorization), and Auto Archive for marketing clutter. The Grammarly acquisition signals deeper AI writing features ahead.

Pricing: Starter at $30/month ($300/year). Business at $40/month ($396/year). Enterprise pricing on request.

Key Features:

• 100+ keyboard shortcuts for mouse-free email triage
• Split Inbox for categorizing emails into custom sections
• AI Auto Drafts, Auto Labels, and Auto Archive
• Read receipts with delivery and open tracking
• CRM integration with HubSpot and Salesforce (Business plan)

Who Should Choose Superhuman

• Professionals processing 200+ emails daily who value raw speed
• Sales teams that need read receipts and CRM integration
• Executives and founders willing to pay a premium for time savings

11. Front

Quick Summary

Front is a shared inbox platform that combines email, chat, SMS, and social media into one collaborative workspace with built-in CRM features. It’s designed for teams, not individuals.

Front turns email into a team sport. Shared inboxes let multiple agents see, assign, and collaborate on customer messages with internal comments and shared drafts. Nobody sends a duplicate reply, and nothing falls through the cracks.

AI features include Copilot for drafting replies, Autopilot for automated resolutions ($0.89/resolution), and Smart CSAT for measuring customer satisfaction without surveys.

Pricing: Starter at $25/seat/month (max 10 seats). Professional at $65/seat/month. Enterprise at $105/seat/month. All billed annually. 14-day free trial.

Key Features:

• Shared inboxes with assignment, commenting, and collision detection
• Omnichannel support for email, chat, SMS, and social media
• AI Copilot for drafting and AI Autopilot for automated resolutions
• Built-in CRM with contact and account management
• Integrations with Salesforce, HubSpot, Slack, and 100+ tools

Who Should Choose Front

• Customer support teams that need shared inboxes with collaboration features
• Operations teams managing high volumes of email across multiple channels
• Companies that want email, CRM, and messaging in a single platform

12. Spike

Quick Summary

Spike transforms email into a conversational chat format with built-in calendar, tasks, notes, video calls, and AI features. It works across desktop and mobile.

Spike displays emails as chat-style conversations, stripping out headers and signatures to show just the message content. This makes email threads easier to follow and faster to skim.

Built-in tools go well beyond email: calendar, task management, collaborative notes, video calls, and voice messages are all included. AI features handle summarization, smart replies, and translation.

Pricing: Free (basic features). Pro at $5/user/month (billed annually).

Key Features:

• Conversational chat-style email display
• Built-in calendar, tasks, notes, and video calls
• AI summarization, smart replies, and translation
• Unified inbox for Gmail, Outlook, Yahoo, and more
• Voice messaging and group chat within email threads

Who Should Choose Spike

• Users who prefer a chat-style interface over traditional email threads
• Small teams that want email, calendar, tasks, and video in one tool
• Budget-conscious professionals who want AI features at $5/month

Comparison Table

#	Email Client	Category	Starting Price	Free Plan?	Platforms	Best For
1	Gmail	Free	Free	Yes	Web, iOS, Android	Best overall free email client
2	Canary Mail	Free	Free	Yes	Windows, Mac, iOS, Android	AI + encryption in one client
3	Thunderbird	Free	Free	Yes	Windows, Mac, Linux	Open-source power users
4	Mailbird	Free	$19.50/yr	Trial	Windows, Mac	Multi-account unified inbox
5	Edison Mail	Free	Free	Yes	iOS, Android, Mac	Ad-free mobile email
6	eM Client	Free	Free	Yes (2 accts)	Windows, Mac	Feature-rich desktop, no subscription
7	Mailspring	Free	Free	Yes	Windows, Mac, Linux	Cross-platform with tracking
8	Proton Mail	Free	Free	Yes	Web, iOS, Android	Privacy and end-to-end encryption
9	Outlook	Paid	$69.99/yr	Web only	Windows, Mac, Web, iOS, Android	Microsoft 365 ecosystem
10	Superhuman	Paid	$30/mo	No	Web, Mac, iOS, Android	Speed and AI for heavy email users
11	Front	Paid	$25/seat/mo	Trial	Web, Mac, Windows, iOS, Android	Team shared inboxes and CRM
12	Spike	Paid	$5/user/mo	Yes	Web, Windows, Mac, iOS, Android	Chat-style email with built-in tools

Getting Email Analytics From Your Email Client

Most email clients show you individual messages, but they don’t show you the bigger picture. How fast is your team responding? How many emails does each person handle per day? Which hours are busiest?

EmailAnalytics fills that gap. It connects to Gmail and Outlook to track your team’s email activity, including average email response time (a critical KPI), emails sent and received per day, and busiest communication hours.

Start Here: Your Email Client Checklist

1. Audit your current email habits. Count how many accounts you manage, how many emails you process daily, and which devices you use most. This determines whether you need a simple client or a power tool.
2. Match the client to your platform. Gmail users benefit most from Gmail’s ecosystem. Microsoft 365 teams should stick with Outlook. Don’t fight your existing infrastructure.
3. Test before committing. Every paid client on this list offers a free trial. Use it for at least a week with your real email volume before subscribing.
4. Track your email performance. Sign up for EmailAnalytics to measure response times and activity patterns. You can’t improve what you don’t measure.
5. Revisit annually. The email client landscape changes fast. Review your choice once a year to make sure it still fits your workflow and budget.

Frequently Asked Questions

What is an email client?

An email client is software that lets you send, receive, read, and organize email messages. Clients come as desktop apps (Outlook, Thunderbird), web interfaces (Gmail), or both. Most modern email clients also include mobile apps for iOS and Android.

What is the best free email client?

Gmail is the best free email client for most users, offering powerful search, smart categories, and a massive add-on ecosystem. For privacy, Proton Mail offers free end-to-end encryption. For a free desktop client, Thunderbird provides open-source flexibility with multi-account support.

Is Outlook free?

Outlook offers a free web version at outlook.com with basic features. The full desktop application requires Microsoft 365, starting at $69.99/year for Personal or $6/user/month for Business Basic.

Is Superhuman worth the price?

At $30/month, Superhuman is worth it for professionals processing 200+ emails daily. Users report saving 4+ hours per week and getting through email twice as fast. For lighter email users, free clients or Spike ($5/month) offer better value.

What is the most secure email client?

Proton Mail is the most secure mainstream email client. It provides end-to-end encryption by default, stores no IP logs, and operates under Swiss privacy laws. It was created by scientists who met at CERN.

Can I use multiple email accounts in one client?

Yes. Mailbird, Thunderbird, eM Client, Spike, and Mailspring all support multiple accounts in a unified inbox. Gmail supports multiple Google accounts plus IMAP connections to other providers. Superhuman supports Gmail and Outlook accounts.

What email client works best for teams?

Front is the best email client for teams needing shared inboxes, internal collaboration, and CRM features. For teams using Gmail, pairing it with EmailAnalytics provides response time tracking and email volume visibility across all team members. Sign up for a free trial to see the data.