Fastmail is great but it’s a totally different market /use case, you wouldn’t go with them if you’re privacy oriented. They’re better than Google in that sense but you’d go with Proton if you’re looking for privacy features.

Also keep in mind Fastmail is based in Australia and their government tends to be anti-privacy with the laws that get passed there.

Proton Mail is great. Can’t compare to fastmail because I’ve never used it. But I enjoy being a paying customer instead of an advertising target and I use every product in their suite. Happy to answer more specific questions

I’ve used Fastmail with a custom domain for a few years now… (5+?) and have been really happy with it. I wish it was a bit cheaper (or had a better family plan), but it works well with my terminal email client (mutt).

The web client is pretty quick and I use the calendar there all the time. Fastmail supports all the normal standards such as CalDAV, so you can use it with third party applications.

I’ve used both and have had good experiences with both. One benefit of Proton is that emails sent to other Proton users are encrypted, but if you mostly just email people who have @gmail.com addresses, then Gmail’s going to store a copy of your emails to that person on their servers anyway.

Both Proton and Fastmail allow you to have a custom domain with a wildcard catch-all address, but the process for replying from that random wildcard address is much more seamless on Fastmail. Proton requires some extra setup and workarounds. But then again Proton is more secure.

It really depends how you use email and what’s important to you (security, convenience, features). I mainly just get junk mail and newsletters. For more private communication I use Signal.

I looked at both, and went with fastmail because at the time it had a shared calendar you could use, which I do with my family to track events and do scheduling. Fastmail is standard commercial privacy though. Good enough for me, but no where near Proton Mail from what I understand.

Note that ProtonMail and Fastmail have quite different feature sets.

ProtonMail does not store your Email in plain text for instance; they cannot read them or be ordered to read them. This comes with some drawbacks such as that standard protocols such as IMAP do not work without a bridge because they necessitates that the server can read all the emails.

I’m happy with fastmail. I haven’t used Protonmail and have had some doubts about them overclaiming about end to end encryption and stuff like that, but they sound good too. The concept of privacy in email is problematic since a) if the person you are emailing uses gmail, then Google has a copy of your email’s plain text no matter how much encryption your own provider uses. b) Even if the email content is encrypted, having the metadata intercepted can be just as invasive, c) even if encrypted, having an archived and authenticated copy of a message can be a big problem due to e.g. rubber hose cryptanalysis, d) for secure communication to exist at all, both people have to be quite security conscious, which isn’t easy. Technical features like cryptography are of very little help with that.

There’s a good movie “Citizenfour” about Edward Snowden, and I remember reading that when the producers needed to have a private conversation while working on the film, they would go outside and talk, leaving their phones in the office. A real privacy approach has to go well beyond using the right email provider.

I like that Fastmail has humans answering support tickets. That’s already light years beyond anything like gmail. I don’t know how Proton is about that. Maybe they can do it for paid plans. I don’t see how they can do it sustainably for free plans but who knows. The main drawback of fastmail is that it is on the expensive side, but I use it so much that it doesn’t sting as much.

If you just want cheap non-megacorp email for your own domains, I like mxroute.com. Their sticker prices can be kind of high, but they frequently have sales with super cheap plans.

I really like Proton.

I’ve used both. I switched from Fastmail to Proton then back to Fastmail. If you’re just starting on your privacy journey I’d still recommend Proton.

When I switched to Proton they only did email and that’s what I wanted. Instead of focusing on email Proton expanded into other areas like VPNs, Proton Drive, and password managers. I already had good privacy focused solutions for all of those problems, so for me personally I didn’t like where they were spending their development time.

As a Linux desktop user and an iOS mobile user I was often one of the last to have new features available for Protons applications which got to be really annoying.

To use desktop email I had to install Proton bridge which required a GUI to run. It was always having issues. Super frustrating.

I really disliked that Proton didn’t give me a way to use SMTP without going through their bridge. I have three home servers configured with Fastmail app passwords limited to only SMTP to send me notifications for updates and other alerts. This would have been really flaky to make work with Proton.

With Fastmail everything uses open standards, IMAP, SMTP, CalDav, CardDav, and WebDav. It all integrates really well with my laptop and phone without any special tools. I end up using those services much more now. The downside to these open standards is you don’t get end to end encryption that Proton offers.

I also feel as if Fastmail is giving me more for my money. I remember having pain points with Proton and wildcard emails with custom domains and trying to use their hidden email service. All of that is much easier with Fastmail. I also had a few sites not allow Protons masked emails but Fastmail worked fine.

I’d say, if privacy is your main thing and you don’t already have some of the services offered by Proton go with them. If what you’re looking for is as much privacy as email will let you have without using non standard software, and you just really want reliable solid email, Fastmail is the right choice.

I’m a proton unlimited subscriber and it’s great. I love the email aliasing from simplelogin, protonvpn, drive storage, calendar, etc. well worth it imo. I love the company.

I tried both. Proton email client on Android at least was awful. Super sluggish to navigate. In fact I have a chunk of credit with them because I cancelled too late to get a refund. No idea what I’m going to do with that. I already have a VPN and a Pwd manager…

Fastmail has been snappy and I like that the app has a notes section for quick jotting of ideas. I also like that Rclone can attach directly to Fastmail files. They just recently added Proton Drive support too though.

I’ve never used Fastmail, so I cannot comment on that but I just closed my Proton account because of their donation to Bellingcat. It might not be a problem for some but it was for me.

https://propagandainfocus.com/proton-mail-imperialist-stooge/

Proton Mail with a custom domain. The only reason why is that I had it before I knew Fastmail existed and it would be a pain in the ass to move my entire family to it. However, I was VERY tempted when 1Password put Fastmail temporary email support into their product.

Fortunately, Proton Mail just released their own temporary email product based on SimpleLogin.

I was using Protonmail, and their other services, and was a paying customer for over a year. But I stopped because of their poor Linux support, and not being able to receive email notifications on my de-googled phone. I made a shift to mailbox.org and am liking it. Yes, I have to manage my own PGP keys, but the experience is much better, in my opinion. Their storage even supports WebDAV. I can encrypt the whole inbox and the files stored in their drive with my own key.

I use both, bit Proton is more fearute rich. Never mind the fact that this is the first company I’ve seen that lowers it’s prices because they are making good money. That alone is worth a shot.