The Complete Email Clients Directory: Desktop, Web, Mobile

What an Email Client Is

An email client is the software you read and write mail in. It connects to a mailbox over a protocol, downloads or synchronises messages, and submits the ones you send. Thunderbird, Outlook, Apple Mail, Mailbird, BlueMail and eM Client are all email clients.

Clients differ on more than layout: they also cap what you can attach, covered in attachment size limits by client and mailbox, and they differ on what they let you undo or delay once a message is written, as in recalling a sent message in Outlook and its real limits and scheduling a message to send later.

The word gets stretched, and the stretch causes most of the confusion on this topic. Gmail and Outlook.com are mailbox services that happen to ship an interface. Thunderbird is an interface with no mailbox behind it: it is useless until you point it at an account somewhere else. Both end up in a directory of email clients because both are what people actually read their mail in, but only one of them is something you can install and aim wherever you like.

The practical consequence is about lock in. A client can be replaced on a Tuesday afternoon without telling anybody, because your mail lives on a server and the client is only a window onto it. Changing provider is a DNS project. Changing client is an afternoon, as long as the account speaks IMAP and SMTP rather than a proprietary protocol.

This directory covers three shapes: desktop applications installed on Windows, macOS or Linux; web interfaces that run in a browser; and mobile applications on iOS and Android. Many products are two or three of those at once.

How to Use This Directory

Start with the table for the platform you are on. Read the pricing and open source columns if either matters to you, and read the last column, which is the only one that says what the client is actually for. Then follow the link on the client name for the download page or the server settings, both of which live on this site.

What this page deliberately does not do is tell you which client is best. There is no such client. The choice is decided by which platforms your team is on, whether you need a calendar in the same window, whether your provider supports IMAP at all, and how many accounts you are juggling. A ranking would hide all four.

Desktop Email Clients

Software you install, which connects to one or more accounts over IMAP, POP3 or a provider protocol. This is where you find the power user features: local search across years of mail, rules, PGP, and offline access.

Web and Mobile Email Clients

Interfaces that run in a browser or on a phone. Most of these come attached to the mailbox service itself, which is why the client and the provider share a name.

Discontinued Email Clients

Recommendations, by Situation

The tables above are the reference. This section is the opinion, and it is deliberately short. Three situations come up constantly, and each has an answer that holds up.

Utilities That Are Not Email Clients

Some tools connect to a mailbox without replacing the software you read it in. They are worth knowing about precisely because they are easy to mistake for clients, and choosing one instead of a client leaves you without an inbox.

Mailbox migration

Migration tools connect to two accounts over IMAP or a compatible protocol, copy messages and folder structure across, and keep the two in step until you are ready to cut over. MailJerry is one such tool. The value is in the synchronisation window: mail continues arriving at the old host while the copy runs, and the tool keeps catching up until DNS moves.

This is a job you meet whenever a domain changes provider, and it is one of the two halves of a migration. The other half is the DNS work, which decides when mail starts arriving at the new host and is where migrations actually fail.

Inbox cleaning and automation

Clean Email and similar services connect to an existing mailbox, group messages into views such as newsletters, notifications or old unread mail, and let you act on thousands at once. Rules then keep future mail sorted. Every change is written back to the account over IMAP, so it shows up in whatever client you actually use.

It fits a specific problem: a mailbox with years of accumulated subscriptions that no amount of manual filing will fix. It does not fit the problem of a client that lacks features, because it is not a client and you still need one for daily reading and sending.

Sending platforms are a different category entirely

One boundary worth stating plainly, because it produces expensive mistakes. An email client is for correspondence. Sending campaigns or application generated mail through the same mailbox puts the account’s limits and your domain reputation in the path of every send. That traffic belongs on an SMTP relay or, at volume, on a platform built for high volume sending. No client in the tables above is a bulk sender, and configuring one as though it were is a reliable way to get an account throttled.

How This Directory Is Maintained

This list is kept by the SMTPedia team from hands on work with these clients in deliverability and support work, rather than compiled from vendor marketing pages or app store rankings.

What we look at for each entry: which protocols it speaks and whether it supports modern authentication; how it handles large mailboxes and multiple accounts at once; how it renders HTML mail, which varies far more than people expect; and whether the vendor is still shipping. That last point is why the discontinued table exists as a separate section rather than as a footnote.

Entries move to the discontinued table when the vendor announces end of life or when releases stop for long enough that the software cannot connect to current providers. Nothing is removed from the page when that happens, because a name that no longer works is exactly the name someone is searching for.

Frequently asked questions