eM Client
Desktop email, calendar, tasks, and chat in one app, with encryption and offline-first sync.
About
eM Client is a Czech-built desktop client for Windows and Mac (with iOS and Android companions) that combines email, calendar, contacts, tasks, notes, and chat. It supports Gmail, Outlook/Exchange, iCloud, and most IMAP providers, with server-side search, PGP and S/MIME encryption, automatic blocking of tracking pixels, instant message translation, snooze, watch-for-reply, and mass mail. The company reports serving over 2.5 million users and 100,000 companies (provider-claimed).
A free tier covers personal, non-commercial use with two accounts; Pro licenses run about $60 one-time or yearly depending on the current lineup. In October 2024 eM Client acquired Postbox and ended that client's development, offering migration discounts to Postbox users. Recent versions added an AI composition add-on and, in v11 (October 2026), a bring-your-own-AI-provider option.
What it can do
- Unified email, calendar, tasks, contacts, notes, and chat
- PGP and S/MIME encryption with tracking-pixel blocking
- Server-side search and instant message translation
- Snooze, watch-for-reply, mass mail, and templates
- AI composition add-on with bring-your-own-provider (v11)
Setup
Download for Windows or Mac, add accounts via the setup wizard, and enable encryption or AI features in settings.
Prerequisites
An email account; paid license for commercial use or more than two accounts.
Use cases
Works with
Trust score — 8/10
Scored 8/10 (verified tier, metrics-v1). Evidence: Czech desktop client (Windows/Mac/iOS/Android): mail, calendar, tasks, contacts, chat, PGP/S-MIME; Acquired Postbox Oct 2024; v11 (Oct 2026) adds AI assistant and bring-your-own-AI-provider; 2.5M+ users / 100k companies is provider-claimed; Pro licenses ~$60 one-time or yearly. License: Proprietary (freemium; free for personal non-commercial use).
How the trust score is built
Full methodology →- Adoption · stars/downloads, log-scaled vs peers
- 8.0/10
- Maintenance · recency, releases, issue load
- 8.0/10
- Openness · license + docs
- 2.0/10
- Manual review · sanity read + red-flag check
- 8.0/10
- · Czech desktop client (Windows/Mac/iOS/Android): mail, calendar, tasks, contacts, chat, PGP/S-MIME
- · Acquired Postbox Oct 2024; v11 (Oct 2026) adds AI assistant and bring-your-own-AI-provider
- · 2.5M+ users / 100k companies is provider-claimed; Pro licenses ~$60 one-time or yearly
Sources
Every fact above was checked against these sources. Where a claim comes from the provider and couldn't be independently verified, the text says so.