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Open source Spark alternatives

Top Email Clients & Providers like Spark

The most popular alternative to Spark is Mailspring, which has a free version. Other great alternatives to Spark are Thunderbird and Proton Mail.

Most alternatives to Spark are in the Email Clients & Providers category, compared here by price, platform and features.

Spark alternatives
AllFreeOpen source
3 apps

All Spark alternatives

  1. Mailspring is a free, open-source desktop email client for Windows, macOS and Linux that works with Gmail, Office 365, iCloud and any IMAP account. It offers a unified inbox, fast search, themes and templates, and runs its mail sync engine locally rather than in the cloud. An optional Pro subscription adds read receipts, link tracking, send later and reminders.

    7 Mailspring alternatives

    Pros

    • Free and open source on Windows, Mac and Linux
    • Sync engine runs locally rather than through a cloud service
    • Unified inbox, themes and templates in a clean interface

    Cons

    • Send later, reminders and read receipts require Pro
    • A Mailspring ID account is required even for the free version
    • No mobile apps to go with the desktop client
    Cost / License
    FreemiumOpen source
  2. Thunderbird is a free and open-source email client for Windows, macOS and Linux, with an Android app based on K-9 Mail. It manages multiple accounts in a unified inbox and includes a calendar, address book, chat and built-in OpenPGP encryption. Add-ons and themes customize it extensively, and it is developed by MZLA Technologies, a Mozilla Foundation subsidiary funded by user donations.

    9 Thunderbird alternatives

    Pros

    • Free and open source, funded by donations rather than ads
    • Built-in OpenPGP encryption, calendar and address book
    • Highly customizable with add-ons and themes

    Cons

    • Interface feels busier than minimalist modern clients
    • Getting the most out of it takes some setup and add-ons
    Cost / License
    FreeOpen source
  3. Proton Mail is an end-to-end encrypted email service based in Switzerland. Messages between Proton users are encrypted automatically, emails to others can be password-protected, and stored mail uses zero-access encryption so Proton cannot read it. Its apps are open source, paid plans add custom domains and more addresses, and it is part of a suite with Proton Calendar, Drive, VPN and Pass.

    9 Proton Mail alternatives

    Pros

    • End-to-end and zero-access encryption protect stored mail
    • Based in Switzerland, with open source apps
    • Part of a suite with Proton Calendar, Drive, VPN and Pass

    Cons

    • Free plan is tight on storage and addresses
    • Using IMAP clients requires Proton Mail Bridge and a paid plan
    Cost / License
    FreemiumOpen source

Spark vs its alternatives at a glance

Pricing, platforms and the key features of Spark, compared with its most popular alternatives.

Spark vs its alternatives at a glance
AppPricingPlatformsAI assistantSend laterTeam collaborationUnified inbox
SparkFreemiumWindows, Mac, iPhone, Android
MailspringFreemiumOpen sourceWindows, Mac, Linux
ThunderbirdFreeOpen sourceWindows, Mac, Linux, Android
Proton MailFreemiumOpen sourceWeb, Windows, Mac, Linux, iPhone, Android

Spark alternatives: frequently asked questions

What is the best alternative to Spark?

The most popular alternative to Spark is Mailspring: Open-source desktop email client for Windows, Mac and Linux. Other great alternatives are Thunderbird and Proton Mail.

Is there a free alternative to Spark?

Yes, 3 alternatives are free or have a free plan, including Mailspring, Thunderbird, and Proton Mail.

Is there an open source alternative to Spark?

Yes, 3 open source alternatives are listed, including Mailspring, Thunderbird, and Proton Mail.

Is Spark free?

Spark has a free plan, with paid plans that unlock more features.

Compare Spark with its alternatives

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