FMail2 is a free, third-party native Mac application that wraps the Fastmail email service in a dedicated macOS window — complete with Dock icon, unread badge, and system notifications. It is not made by Fastmail; it is an independent open-source project built by developer Arie van Boxel.
What is FMail2?
FMail2 is a macOS wrapper that takes Fastmail's full web interface and promotes it to a proper desktop application, bypassing the browser entirely. Rather than connecting to Fastmail over IMAP and reconstructing a generic mail view the way Apple Mail does, FMail2 loads the genuine Fastmail web app — every rule builder, calendar tab, masked-email generator, and keyboard shortcut intact — inside a self-contained native shell. Open it from the Dock, switch to it with Cmd-Tab, and leave browser distractions behind in one move.
What does FMail2 do best?
The clearest win is focus. Fastmail's web app is excellent, but living in a browser tab means it competes with every other open URL for your attention and is one accidental Cmd-W away from vanishing. FMail2 solves that permanently. It gives you a fixed, always-available home for email that sits in the Dock exactly where you'd expect a mail client to be.
Because the full Fastmail interface runs inside the wrapper, nothing gets lost in translation. All of Fastmail's signature capabilities — snooze, scheduled send, custom filtering rules, JMAP-powered speed, and the integrated contacts and calendar — work exactly as Fastmail designed them. There is no feature-parity gap to worry about, no plugin to install, and no IMAP quirks to debug. The biggest change you'll notice after switching is simply that you stop losing your Fastmail tab.
Is FMail2 free?
FMail2 is free to download directly from the developer's website. The only real cost involved is your existing Fastmail subscription — Fastmail is a paid email service, and FMail2 requires a Fastmail account to be of any use whatsoever. Think of it as a no-cost upgrade on top of a service you're already paying for, not a separate product with its own price tag. As an independently maintained open-source project, it does not carry its own subscription, trial period, or in-app purchase.
Who should use FMail2?
Fastmail subscribers who treat email as a genuine work tool. If you rely on Fastmail's filtering logic, reach for masked emails to protect your privacy, or depend on keyboard shortcuts to triage your inbox quickly, you already know how good the web UI is — FMail2 simply moves it out of the browser where it belongs. It is also a natural fit for anyone who prefers macOS system notifications over browser push alerts, which tend to be unreliable and easy to miss.
If you barely open Fastmail once a day, the browser tab is probably fine. For anyone whose inbox is genuinely part of their daily workflow, though, a dedicated window removes a surprising amount of friction.
How does FMail2 compare to Apple Mail?
Apple Mail connects to Fastmail via IMAP and CardDAV — it is fully native, Spotlight-indexable, and supports Handoff across your Apple devices. What it cannot replicate is Fastmail's own interface. The rule builder, masked email dashboard, calendar UI, and a handful of JMAP-specific speed optimisations are web-only features that simply do not travel over IMAP. FMail2 keeps all of that intact, at the cost of feeling more like a web app in a chrome than a truly native client. I run both: Apple Mail for Spotlight-searching old threads, FMail2 for everything I actually do in Fastmail day to day.
What are the best FMail2 alternatives?
The realistic alternatives for Fastmail users fall into two camps. Native IMAP clients — Apple Mail (free), Airmail 5 (subscription), and Canary Mail (privacy-focused, subscription) — all speak Fastmail fluently but surrender the web interface in the process. Generic site-wrapper tools — Fluid and Unite — let you build your own Fastmail app, but they ship with no Fastmail-specific defaults and require meaningful setup time. Spark is worth knowing about for households juggling Gmail and other accounts alongside Fastmail; Mimestream is superb but Gmail-only. FMail2 remains the only wrapper that arrives pre-configured specifically for Fastmail, making it the lowest-friction option for existing subscribers who simply want a dedicated app.
