If you have decided to leave Gmail behind, two names come up again and again: Fastmail and Proton Mail. They are both excellent, both paid, and both built by companies that take email seriously, but they are aiming at slightly different people. Fastmail is the fast, no-nonsense workhorse for anyone who lives in their inbox and wants it to be quick and flexible. Proton Mail is the privacy-first option built around end-to-end encryption and a Swiss legal home. Picking the right one comes down to what you actually want email to do for you.
We have used both extensively, and below we break down how they compare on the things that matter: privacy and encryption, speed and usability, custom domains, the wider ecosystem, and price.
The quick verdict
If your priority is the maximum privacy that email can realistically offer, with messages encrypted so that not even the provider can read them, Proton Mail is the one to pick. If your priority is a fast, flexible, genuinely pleasant daily email experience with first-class support for your own domains, Fastmail is the better tool, and it is the one we reach for ourselves. Both respect you far more than the free ad-supported services do.
Privacy and encryption
This is where the two diverge most sharply. Proton Mail is built around zero-access, end-to-end encryption: your mailbox is encrypted in a way that means Proton itself cannot read your messages, and emails between Proton users are encrypted automatically. Combined with its base in Switzerland and strong privacy laws, it is the stronger choice for anyone whose threat model includes the provider itself, or who simply wants the highest assurance available.
Fastmail takes privacy seriously too. It does not scan your mail to sell ads, its business model is simply you paying for the service, and it has a clear, privacy-respecting stance. What it does not do is zero-access encryption, because the data is encrypted at rest and in transit but Fastmail can technically access it to provide features like fast server-side search. For most people that is a perfectly reasonable trade, but if end-to-end encryption is non-negotiable, Proton wins outright.
Speed and usability
Fastmail lives up to its name. The web app is quick, search is instant, and the whole experience feels lightweight in a way that Proton, with its encryption overhead, does not quite match. Power-user features like rules, aliases, and snoozing are well thought out, and the apps are reliable across platforms. For someone who processes a lot of mail every day, Fastmail simply gets out of the way.
Proton Mail has improved enormously and its apps are now clean and capable, but the encryption that makes it special also adds a little friction. Search, for example, has historically been more limited because the server cannot read your encrypted mail, though Proton has addressed this with client-side search. If raw speed and a frictionless interface top your list, Fastmail has the edge.
Custom domains
Both let you use your own domain, which is essential if you want a professional address like you@yourname.com. Fastmail has long been a favorite here because setting up and managing domains is straightforward, alias handling is excellent, and it works smoothly whether you are an individual or running email for a small team. Proton supports custom domains on its paid plans too, and does so well, but Fastmail’s flexibility with aliases and multiple domains is hard to beat for people who like to compartmentalize their email.
Fastmail is our pick for everyday email
Fast, flexible, and privacy-respecting, with the best custom domain and alias handling of any provider. There is a free trial so you can move your mail across and see for yourself.
The wider ecosystem
Proton has built a whole privacy suite around its mail: Proton VPN, Proton Drive, Proton Calendar, and Proton Pass all share one account and one privacy philosophy. If you want to consolidate your private life across email, storage, passwords, and VPN under a single trusted provider, that bundle is genuinely appealing and good value at the higher tiers.
Fastmail is more focused. It does email and calendar and contacts extremely well, and integrates cleanly with standard protocols so it plays nicely with the apps you already use, but it is not trying to be your VPN or password manager. Whether that focus is a strength or a limitation depends on whether you want one company handling everything or prefer best-of-breed tools.
Pricing
The two are broadly comparable on price for individual paid plans, and both are far cheaper than the cost of having your data mined by a free service. Proton offers a limited free tier, which Fastmail does not, so if you want to test encrypted mail at no cost Proton gives you that on-ramp. Fastmail counters with a free trial and, for many people, better value once you account for how much you actually use the product day to day. Proton’s bundles become more attractive the more of its other services you adopt.
So which should you choose?
Choose Proton Mail if end-to-end encryption and maximum privacy are your top priority, or if you want to build your whole digital life around one privacy-focused ecosystem. Choose Fastmail if you want the fastest, most flexible everyday email with superb custom domain support and a clean, frictionless experience. Both are great. The honest tiebreaker is this: most people who just want excellent email will be happier with Fastmail, while those with specific privacy requirements should go with Proton. You will not regret either.
