Email client software is the program you read and write mail in, from free desktop apps to paid team inboxes.
This guide ranks eleven products on what the first ninety days cost, what the licence becomes once tracking or AI is added, how mail leaves again, and whether you can run without a partner.
Vendors can pay for visibility on this page. It never changes what an entry
says about a product, including the criticism, and we earn nothing when you click through to a
vendor. How that works.
In short
What email client software does
An email client is software that connects to mailboxes and lets you read, write, search and organise messages on a desktop or phone, separate from the mail service itself.
In this order: setup effort, what it really costs, how your data comes back out, whether
you can leave, and who each email client tool is built for. One rule sits on top of those tests:
Places 1 to 3 go to challengers, vendors outside the best-known brands in a category, wherever the category has them; the established names follow from place 4 in their ranked order. Why those five, and why there is no
score out of ten, is on the how we work page.
Published per-seat monthly plans, priced by AI tier; 14-day trial
—
Gmail-centred professionals who search and draft with an AI assistant daily
Budget buyers or teams wanting email software with no AI cost attached
Country is where the vendor is headquartered or contracts from, which is a
different question from where your data is hosted. Where the two tell different stories, the
entry says so.
Prague-made Windows and macOS mail client, rented yearly or bought once
Ranked #1 of 11 in Best Email Client Software in 2026.
Free tierPublished pricingEurope
eM Client scores best on the exit and independence tests: one Czech company, one program, and a choice between renting and buying. Yearly plans bundle an AI add-on, one-time licences leave the add-on out.
Business licences are counted per device with volume discounts and a licence manager. Budget for the yearly plan if you want AI, and for Lifetime Upgrades if you want to keep buying once.
What stands out
Subscription or one-time licence
Windows and macOS
PGP and S/MIME
Where it costs you
The free tier allows two email accounts and no commercial use
A one-time licence covers the current major version only; later versions need a Lifetime Upgrades purchase
Right for
Individuals and small offices wanting one desktop program with a perpetual-licence option
Wrong for
People on Linux, since only Windows and macOS builds are listed
CzechiaPublished; free tier for home use, yearly subscription or one-time licence; 30-day trial
Keyboard-driven IMAP client for macOS from a Copenhagen studio
Ranked #2 of 11 in Best Email Client Software in 2026.
Published pricingEurope
MailMate is the smallest recommendable vendor in this list and its licence is unusual: a subscription pays for ongoing development, the trial lasts 14 days of active use, and afterwards the program keeps working in Free Mode with a header stating that mode.
Businesses are expected to hold a paid key. Setup takes an hour if you already use IMAP, and a day if you want smart mailboxes tuned.
What stands out
macOS only
IMAP only
Markdown composing
Where it costs you
It speaks IMAP and runs on macOS only; the site lists no Windows or phone version
Stopping the subscription adds a Free Mode marker to the headers of outgoing mail
Right for
Mac users who live on the keyboard and want Markdown mail and deep search
Wrong for
Anyone needing Windows, a phone app or non-IMAP accounts
DenmarkPublished subscription that funds development; trial runs 14 days of active use, then Free Mode
Native Mac client on the Gmail API, from a bootstrapped small team
Ranked #3 of 11 in Best Email Client Software in 2026.
Published pricingNorth America
Mimestream wins on fit for one narrow buyer: Gmail on a Mac. The 14-day trial is fully functional and needs no card, and one subscription covers up to five devices plus immediate family.
Group licences add central billing and seat management. The cost of the narrow focus is exit: a subscriber who later adds a non-Google mailbox needs a second client. The vendor also sells direct, not via the App Store.
What stands out
Gmail API
macOS native
Subscription only
Where it costs you
It connects Google accounts only, so Outlook or IMAP mailboxes cannot be added
No one-time purchase exists, only a monthly or annual subscription
Right for
Mac users whose mail is Gmail or Google Workspace and who want native speed
Wrong for
Teams with Outlook, Exchange or other IMAP mailboxes in the mix
United StatesPublished subscription, monthly or annual, per user or per group seat; 14-day trial without card
Donation-funded desktop client for Windows, Linux and macOS, with an Android app
Ranked #4 of 11 in Best Email Client Software in 2026.
Free tierOpen sourcePublished pricingElsewhere
Thunderbird answers the independence test better than anything else here: nothing to buy, nothing to cancel, files kept locally. Its pages state that no ads are sold in the inbox and that private mail is not used to train AI.
It has a unified inbox, tags and calendars. Plan for setup effort on your own, since no onboarding service is listed, and expect to bring your own filters and add-ons.
What stands out
Open source
Windows, Linux, macOS
Unified inbox
Where it costs you
Funding is by donation, and the home page lists no paid support or team features
The mobile app is offered for Android only, via Google Play and F-Droid
Right for
Individuals and small offices wanting a free desktop client with a transparent licence
Wrong for
Teams wanting shared inboxes, assignments or a vendor service-level agreement
Not stated by the vendorFree to download and use; funded by user donations
Windows and Mac client with a one-account free tier and pay-once Premium
Ranked #5 of 11 in Best Email Client Software in 2026.
Free tierPublished pricingNorth America
Mailbird's real price depends on two toggles on the pricing page: lifetime updates and the Leave Me Alone add-on, each priced separately from the licence. Without them, pay-once buys the current version only.
Volume discounts of 5 to 25 percent apply from two licences upward. The 14-day money-back window is short for a rebuilt product, so test IMAP accounts and Exchange support in that period.
What stands out
Free tier
Pay-once licence
Windows and Mac
Where it costs you
Mailbird Next does not support POP3 accounts yet
Pay-once licences exclude future major versions unless the lifetime-updates add-on is bought
Right for
Windows users wanting several accounts in one window with an optional one-off payment
Wrong for
Owners of POP3 mailboxes or anyone needing an app on Linux
United StatesPublished; free tier with one account, Premium yearly or pay-once; 14-day money-back guarantee
Cross-platform client with GPL source; tracking and send later need Pro
Ranked #6 of 11 in Best Email Client Software in 2026.
Free tierPublished pricingElsewhere
Mailspring serves a niche that others skip, Linux, and keeps the free version usable with unified inbox, search, undo send and signatures.
The cost appears when you want sales-style features: Pro adds tracking, templates and reminders per month and per person. Exit is simple since mail stays in your IMAP accounts. The site names the company but no country, so check the legal entity for contracts.
What stands out
Mac, Windows, Linux
GPL v3 repository
Pro adds tracking
Where it costs you
Read receipts, link tracking and send later are Pro features
The full calendar view is announced as coming later, not yet shipped
Right for
Linux users wanting a graphical client with unified inbox and a paid tracking tier
Wrong for
Teams needing shared inboxes or a ready calendar view
Not stated by the vendorFree version; Pro subscription with published monthly price
Team inbox mixing email, SMS and chat apps, priced per user
Ranked #7 of 11 in Best Email Client Software in 2026.
Published pricingNorth America
Missive sits at the team end of this list, which is why it lands mid-table: it is built to replace shared-mailbox workarounds, not to be one person's desktop client.
Each user may connect up to ten personal and five shared accounts. SOC 2 Type II compliance is stated. Count seats of occasional users too, because they are billed like heavy users.
What stands out
Shared inbox
Email, SMS, WhatsApp
SOC 2 Type II
Where it costs you
Starter allows up to five users; integrations, rules and API access start at Productive
Per-seat billing makes it expensive for one person who only needs a mail window
Right for
Small teams sharing support, sales or client mailboxes across email and messaging channels
Wrong for
Single users wanting a plain inbox without team collaboration
CanadaPublished per-user plans, billed yearly or monthly; 30-day trial without card
One-user licence for four platforms with free, yearly and lifetime options
Ranked #8 of 11 in Best Email Client Software in 2026.
Free tierPublished pricingElsewhere
Canary Mail is cheap at entry and clear about tiers. After seven days at full strength the account drops to Free without a card, so nothing is charged by surprise.
Growth costs about three dollars a month billed yearly, Pro+ about ten, and both can be bought for life. Encryption is the reason to pick Pro+: PGP, SecureSend and impersonation detection are missing from lower tiers.
What stands out
Free tier
Lifetime option
PGP in Pro+
Where it costs you
There is no monthly billing; paid plans run yearly or as a lifetime purchase
Each licence is for one user, with device caps of two on Free and five on paid plans
Right for
Individuals wanting one licence across four platforms with optional encryption
Wrong for
Teams needing shared inboxes or per-seat admin controls
Not stated by the vendorPublished; free tier, yearly or lifetime purchase; 7-day trial of paid features
37signals mail and calendar service with a Screener for unknown senders
Ranked #9 of 11 in Best Email Client Software in 2026.
Published pricingElsewhere
HEY changes the model rather than the window, so the setup test is a migration, not an install. Personal use is a yearly fee for a hey.com address with 100 GB, and HEY for Domains is monthly per user with shared threads and private comments.
Spy pixels are blocked. The 30-day trial needs no card, and trial users can export mail and contacts when they leave.
What stands out
Screener
Own mail service
Mac, Windows, Linux, iOS, Android
Where it costs you
It replaces your mail provider, so it cannot manage existing Gmail or Outlook accounts
Ultra-short hey.com addresses cost far more than the standard yearly price
Right for
Individuals and small firms ready to move their address into a screening workflow
Wrong for
Anyone who must keep an Exchange or Gmail mailbox
Not stated by the vendorPublished; yearly personal price or monthly per-user price for domains; 30-day trial without card
Readdle's multi-account client with team drafts and comments, free for personal use
Ranked #10 of 11 in Best Email Client Software in 2026.
Free tierPublished pricingEurope
Spark gives away the multi-account inbox and charges for collaboration and AI, which makes the free start cheap and the team bill grow per seat.
Plus is listed at ten euro per user monthly and Pro at twenty-two, with yearly discounts shown. Free allows two collaborators and ten assignments per team. Compare the AI quota lines before you commit a whole team.
What stands out
Free tier
Team drafts and comments
AI quotas by plan
Where it costs you
Meeting notes are capped at five for life on Free and 40 a month on Plus
Auto-Drafts, read statuses and unlimited meeting notes require the top self-serve plan, Pro
Right for
Small teams that draft and discuss email together and want a free starting point
Wrong for
Buyers wanting AI included at a flat price with no usage caps
UkrainePublished; free tier, Plus and Pro per user monthly or yearly, Enterprise quoted; 7-day trial
AI-centred client with seat plans that rise with the model tier
Ranked #11 of 11 in Best Email Client Software in 2026.
Published pricingElsewhere
Shortwave ranks last because its price is tied to AI consumption: the same inbox costs more or less depending on the intelligence level and the quota.
Business lists a five-year AI search history, Premier unlimited. Threads per AI search climb from 50 to 150. A 14-day trial helps you measure how many requests a person actually uses before picking a tier.
What stands out
AI assistant
Per-seat tiers
Gmail-style search
Where it costs you
The Business tier carries a daily AI quota of roughly 150 to 300 standard requests
The cost per seat rises fourfold from Business to Max for more AI capacity
Right for
Gmail-centred professionals who search and draft with an AI assistant daily
Wrong for
Budget buyers or teams wanting email software with no AI cost attached
Not stated by the vendorPublished per-seat monthly plans, priced by AI tier; 14-day trial
An email client is software that connects to mailboxes and lets you read, write, search and organise messages on a desktop or phone, separate from the mail service itself. The differences that matter are rarely in the feature list, so this is
the order we would work through them.
01
Decide whether you need a published price
11 of the 11 tools here publish what they cost; the other 0 quote per organisation. The ones you can compare without a sales call: eM Client, MailMate, Mimestream, Mozilla Thunderbird, Mailbird, Mailspring, Missive, Canary Mail, HEY, Spark, Shortwave.
02
Decide how much the jurisdiction matters
These 11 vendors are established in 6 countries across 3 regions (Elsewhere 5, North America 3, Europe 3). That decides whose disclosure law applies to what the vendor holds, wherever the servers are.
03
Consider whether you want the source
1 of these are open source: Mozilla Thunderbird. Hosting one yourself trades a subscription for maintenance.
A client, a mail service or a team inbox: three different products
Email client software hides three products behind one label. Thunderbird, MailMate and eM Client are desktop programs that read mailboxes you already own. HEY is a mail service with its own apps, so choosing it means moving your address. Missive is a team inbox where several people share conversations and mix in SMS and chat channels.
Buying the wrong kind costs the first quarter: a team that picks a single-user client has to bolt on shared mailboxes later, and a person who picks a team tool pays per seat for features nobody uses. Decide first whether the mailbox stays where it is, whether more than one person answers it, and whether you want to leave your current provider.
Write down whether you keep your current mail provider or move it.
List who else must see or answer the mailbox.
Check that the client connects your account type before trialling.
Subscription, one-time licence or donation: how clients charge
Pricing models split the field. eM Client and Mailbird sell both a yearly subscription and a one-time licence, but a one-time licence covers the current major version, so later versions cost extra. Mimestream and MailMate are subscription only. Canary Mail sells yearly or lifetime, and never monthly. Missive and Shortwave bill per seat per month, which scales with headcount.
Thunderbird is free and funded by donations. The cheapest first year is rarely the cheapest fifth year, so price five years including upgrades, add-ons and the extra seats of part-time users, then compare that total with the cost of a free client plus your own setup hours. Vendors also change terms, so note the date you checked the price page.
Price five years, including upgrade fees for one-time licences.
Count part-time users as full seats for per-seat tools.
Ask what happens to your mail and settings when payment stops.
Gmail-only, IMAP or POP3: what the client can connect
Account support differs more than feature lists suggest. Mimestream connects Google accounts only, through the Gmail API. MailMate works with IMAP accounts on macOS. Mailbird Next did not yet support POP3 on its pricing page, and eM Client and Thunderbird cover desktop mail on several systems. Shortwave describes its multi-account use around Gmail accounts. The account type decides which of these can even start.
A Microsoft Exchange or Outlook mailbox, a shared company address or an old POP3 account each rules out some candidates before price or design come into play, so list your mailboxes and their protocol before you read any feature table. Ask also whether the client keeps a local copy of mail, because that decides what you can read offline and what you keep if you leave.
List each mailbox with its provider and protocol before shortlisting.
Test the oldest and the most unusual account first.
Confirm shared mailboxes and aliases work in the trial.
Tracking, AI and encryption: which features sit behind the paywall
The extras that sell paid plans are tracking, AI and encryption, and they are spread unevenly. Mailspring keeps read receipts, link tracking and send later in Pro. Canary Mail puts the AI Copilot in Growth and PGP in Pro+. Spark meters meeting notes and AI by plan, and Shortwave ties its quota to the AI tier.
Read-receipt tracking also depends on the recipient, because HEY and Mimestream block tracking pixels and your tracked mail may be hidden from some readers. Pick the feature you would pay for on its own, then check which plan holds it and what its monthly limit is, before comparing the base price. A cheap plan whose monthly allowance runs out in week two behaves like a free one.
Name the one extra you would pay for and find its plan.
Read the monthly quota for AI and meeting notes.
Check whether encryption needs the top tier.
What goes wrong most often when buying email client software
Choosing a client by its feature list before listing the mailboxes and protocols it must connect.
Treating a one-time licence as permanent, when it covers only the current major version.
Counting only heavy users when a per-seat tool bills occasional users the same.
Relying on read receipts and link tracking as proof of reading, when clients such as HEY block tracking pixels.
07
Frequently asked questions
7 answers
What is the best email client software in 2026?
eM Client leads our ranking of 11. eM Client s.r.o. in Prague sells one desktop program for Windows and macOS with a free tier, a yearly subscription and a one-time licence, plus a business variant counted per device.
The free tier stops at two accounts and home use. A one-time licence covers only the current major version, so later versions cost extra.
Which email client tools publish their pricing?
11 of the 11, with the pricing model each one publishes:
eM Client: Published; free tier for home use, yearly subscription or one-time licence; 30-day trial.
MailMate: Published subscription that funds development; trial runs 14 days of active use, then Free Mode.
Mimestream: Published subscription, monthly or annual, per user or per group seat; 14-day trial without card.
Mozilla Thunderbird: Free to download and use; funded by user donations.
Mailbird: Published; free tier with one account, Premium yearly or pay-once; 14-day money-back guarantee.
Mailspring: Free version; Pro subscription with published monthly price.
Missive: Published per-user plans, billed yearly or monthly; 30-day trial without card.
Canary Mail: Published; free tier, yearly or lifetime purchase; 7-day trial of paid features.
HEY: Published; yearly personal price or monthly per-user price for domains; 30-day trial without card.
Spark: Published; free tier, Plus and Pro per user monthly or yearly, Enterprise quoted; 7-day trial.
Shortwave: Published per-seat monthly plans, priced by AI tier; 14-day trial.
The other 0 quote per organisation.
Is there a free email client tool?
eM Client, Mozilla Thunderbird, Mailbird, Mailspring, Canary Mail, Spark offer a free tier or a free self-hosted edition.
Where are these email client software vendors established?
In 6 countries across 3 regions: Elsewhere 5, North America 3, Europe 3.
eM Client: Czechia.
MailMate: Denmark.
Mimestream: United States.
Mozilla Thunderbird: Not stated by the vendor.
Mailbird: United States.
Mailspring: Not stated by the vendor.
Missive: Canada.
Canary Mail: Not stated by the vendor.
HEY: Not stated by the vendor.
Spark: Ukraine.
Shortwave: Not stated by the vendor.
Which email client tools are open source?
Mozilla Thunderbird.
What should you use instead of eM Client?
MailMate and Mimestream are the next two on this page. MailMate is for Mac users who live on the keyboard and want Markdown mail and deep search; Mimestream is for Mac users whose mail is Gmail or Google Workspace and who want native speed.
Who should not buy eM Client?
People on Linux, since only Windows and macOS builds are listed. The free tier allows two email accounts and no commercial use.
If your email client software product belongs among these 11, tell us what it does and who it is for. Inclusion is an editorial call; what a listing is and is not is set out under software advice.
