eM Client 11 lets you bring your own key

eM Client 11 went out on 7 October. The Prague company has been building the same desktop mail client for years — Windows and macOS, with free Android and iOS apps that need no licence — and this release is the biggest one it has shipped. Most of what is new is AI: an assistant that lives in the sidebar and follows you through mail, calendar, contacts and tasks; one-click replies; a writing composer; summarise on a message or a whole thread; search you can type as a sentence instead of a query; rules you describe rather than build.

That list reads like every mail client's 2026 checklist. What matters is where the AI comes from, because eM Client made two choices most clients have not.

The model is not the product

First: Bring Your Own Key. Organisations running eM Client 11 can point the assistant at a compatible provider and model of their choosing instead of a bundled service. The mailbox data sits in the client on your machine; the model is whoever you signed with. On a mail client — the one app that holds every contract, invoice and private thread you have ever received — that separation is what keeps your mail under your control. It is not "European AI". It is the client's maker declining to become your AI provider.

Second: the client now speaks MCP, the Model Context Protocol. External assistants and agents can be granted controlled, read-side access to email data and supported app functions, which turns a closed desktop application into a data surface other tools can work with. Copilot in Outlook works the other way around — Microsoft holds the mailbox and the model in the same cloud. Here the client stays local, the agent is external, and the access is a permission you grant rather than an architecture you accept.

The timing helps them. Microsoft started phasing out Exchange Web Services for Microsoft 365 accounts this month, and eM Client 11 adds Microsoft Graph support in the same release — the protocol bridge Exchange shops were going to need anyway.

Owning the client does not own the AI

The pricing page keeps one honest wrinkle. eM Client still sells a perpetual licence — $74.95 Personal, $89.95 Business, one payment, yours for the current major version. But the AI is not in that box. Perpetual holders get the AI features through an add-on subscription from $3 per month per seat. The yearly licences ($49.95 Personal, $59.95 Business per device) bundle the same add-on, which the site values at $30. You can own the client outright and still rent the assistant.

The free tier stays genuinely free — two accounts, home use, no AI — and the mobile apps cost nothing at all. A 30-day trial and a 30-day money-back window cover the rest.

European mail in this directory mostly means services: Proton Mail and Tuta are places your mail lives. eM Client is the other kind — a client that sits in front of whatever IMAP, Exchange or Google account you already have and leaves the hosting question to you. Version 11 extends the same instinct to the model layer: your key, or theirs, but the mailbox never becomes someone else's training set by default.

Whether BYOK actually reaches the model you want is the open question, and it is the one worth asking before the trial runs out. But the shape of the offer is right: a client you can buy, an assistant you can replace.