Best Free Email Clients 2026: 8 Options Compared
Best free Email Clients compared: Thunderbird, Mailspring, eM Client, Microsoft Outlook and 4 more, with free-plan limits, platforms and prices from official pages checked October 24, 2026.
•3 min read•Email, Calendar & Scheduling
Quick comparison
| Tool | Price | Platforms | Best for | Tested |
|---|---|---|---|---|
| Thunderbird | Free (Free and open-source desktop mail client; no paid plan stated on the about page) | Windows, macOS, Linux | The default open-source client | Docs only |
| Mailspring | Free (Free tier includes unified inbox, snooze, send later, rules and templates) | Windows, macOS, Linux | A modern interface on desktop | Docs only |
| eM Client | Free (Free version: 2 email accounts, registration required, home use on 1 device); paid from $49.95 per year (Personal, 3 devices; Business $59.95 per device per year) | Windows, macOS, iOS, Android | One or two personal accounts | Docs only |
| Microsoft Outlook | Free (Free Outlook.com mailbox and web app; the desktop client comes with Microsoft 365 plans) | Windows, macOS, iOS, Android, Web | Microsoft users | Docs only |
| Gmail | Free (No-cost plan with 15 GB pooled storage per user) | Web, iOS, Android | Web-first email | Docs only |
| Proton Mail | Free (Up to 1 GB (500 MB at start, rising to 1 GB after a setup checklist)); paid from $3.99 per month, billed annually (Mail Plus; $47.88 every 12 months) | Web | Encrypted personal email | Docs only |
| Zoho Mail | Free (Forever Free: up to 5 users, 5 GB mail storage per user, one domain) | Web, iOS, Android | Small teams on their own domain | Docs only |
| Tuta | Free (1 GB storage, 1 calendar, 3 labels, no custom domain) | Web, iOS, Android | Encrypted mail with a calendar | Docs only |
Independent comparison. Paid placements are labelled separately; editorial links earn no affiliate commissions. Learn more.
Good fit if
- You want one desktop inbox for many accounts (Thunderbird is the pick)
- You like a polished interface and snoozing (Mailspring is the pick)
- You want encrypted mail (Proton Mail is the pick)
- You need a small team on a custom domain (Zoho Mail is the pick)
Not ideal if
- You need paid-tier features, uptime guarantees or support that these free plans leave out
An email client is software on your computer or phone that collects mail from your existing accounts, so free usually means free software rather than a free mailbox. Thunderbird is the standard open-source choice for Windows, macOS and Linux, with a built-in calendar and no cost. Mailspring is a modern GPL-3.0 client with unified inbox, snooze, send later and templates free, and a monthly Pro subscription for tracking features. eM Client's free version is limited to two accounts and home use on one device, and the Personal plan costs $49.95 a year. Outlook and Gmail are free as web mailboxes, and their apps work as clients for other providers too. If you want privacy rather than convenience, Proton Mail and Tuta give free mailboxes with 1 GB, and Zoho Mail's Forever Free plan covers up to five users on one domain. The trade-off is that mailbox providers lock you into their address, while a client lets you keep existing addresses and switch providers later. Check IMAP support for your account, since that is what makes mail sync across devices. If you manage several accounts and want one inbox, pick Thunderbird or Mailspring first; if you only use one account, the provider's own app is usually enough.
Thunderbird
MPL-2.0 desktop client for Windows, macOS and Linux with a built-in calendar. No paid plan is stated; donations are voluntary. Phone sync needs a separate app.
Price: Free (Free and open-source desktop mail client; no paid plan stated on the about page) (Thunderbird pricing, checked 2026-10-23).
Platforms and license: Windows, macOS, Linux. MPL-2.0 (open source).
Best for: The default open-source client.
Mailspring
GPL-3.0 client for Windows, macOS and Linux. Unified inbox, snooze, send later, rules and templates are free; link tracking and read receipts need Pro.
Price: Free (Free tier includes unified inbox, snooze, send later, rules and templates) (Mailspring pricing, checked 2026-10-24).
Platforms and license: Windows, macOS, Linux. GPL-3.0 (open source).
Project activity: 18k GitHub stars · latest release 1.26.2 (Oct 22, 2026) · last commit Oct 27, 2026
Best for: A modern interface on desktop.
eM Client
Free version covers 2 accounts for home use on 1 device and needs registration. Personal is $49.95 a year for 3 devices.
Price: Free (Free version: 2 email accounts, registration required, home use on 1 device); paid from $49.95 per year (Personal, 3 devices; Business $59.95 per device per year) (eM Client pricing, checked 2026-10-24).
Platforms and license: Windows, macOS, iOS, Android. Proprietary.
Best for: One or two personal accounts.
Microsoft Outlook
Free Outlook.com mailbox and web app; the desktop client comes with Microsoft 365. The Microsoft pricing page timed out, so no paid price is stated.
Price: Free (Free Outlook.com mailbox and web app; the desktop client comes with Microsoft 365 plans) (Microsoft Outlook pricing, checked 2026-10-23).
Platforms and license: Windows, macOS, iOS, Android, Web. Proprietary.
Best for: Microsoft users.
Compare: Microsoft Outlook alternatives
Gmail
No-cost plan with 15 GB pooled storage. Works through the web and mobile apps, and as an account in other clients.
Price: Free (No-cost plan with 15 GB pooled storage per user) (Gmail pricing, checked 2026-10-23).
Platforms and license: Web, iOS, Android. Proprietary.
Best for: Web-first email.
Compare: Gmail alternatives
Proton Mail
Free plan holds up to 1 GB with end-to-end encryption. Mail Plus is $3.99 a month billed annually.
Price: Free (Up to 1 GB (500 MB at start, rising to 1 GB after a setup checklist)); paid from $3.99 per month, billed annually (Mail Plus; $47.88 every 12 months) (Proton Mail pricing, checked 2026-10-23).
Platforms and license: Web. Proprietary.
Best for: Encrypted personal email.
Compare: Proton Mail alternatives
Zoho Mail
Forever Free plan for up to 5 users, 5 GB per user and one domain. The sixth user moves you to a paid plan.
Price: Free (Forever Free: up to 5 users, 5 GB mail storage per user, one domain) (Zoho Mail pricing, checked 2026-10-23).
Platforms and license: Web, iOS, Android. Proprietary.
Best for: Small teams on their own domain.
Tuta
Free plan with 1 GB storage, 1 calendar, 3 labels and no custom domain. Check the pricing page for current paid plans.
Price: Free (1 GB storage, 1 calendar, 3 labels, no custom domain) (Tuta pricing, checked 2026-10-23).
Platforms and license: Web, iOS, Android. Proprietary.
Best for: Encrypted mail with a calendar.
Which one to pick
- You want one desktop inbox for many accounts: Thunderbird
- You like a polished interface and snoozing: Mailspring
- You want encrypted mail: Proton Mail
- You need a small team on a custom domain: Zoho Mail
Limits of this review
Docs-only for Thunderbird, Mailspring, eM Client, Microsoft Outlook, Gmail, Proton Mail, Zoho Mail, Tuta: we did not install or run them, so feature claims come from vendor pages. Vendor prices and free limits change; confirm on the linked pricing page before you commit.
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Kevin Fan
Kevin Fan is a SaaS founder. He runs Free Instead Of, which tracks free and open-source alternatives to paid software and checks each price and free-plan limit against the vendor's own pages.
Methodology
Based on official pricing, license and product pages checked between 2026-10-23 and 2026-10-24: Thunderbird, Mailspring, eM Client, Microsoft Outlook, Gmail, Proton Mail, Zoho Mail, Tuta. Prices, free limits and licenses are the figures shown on those pages on those dates. No tool on this page was installed or run. No accounts were created.