I use Proton Mail. I recommend that whatever service you decide on, get your own domain name so you can keep your email address if you move to a different provider.
Skiff gives you 10 GBs of storage and also comes with a drive and a Notion-like Pages app. They even let you add custom domain for free. The only disadvantages are the non-native Android or iOS apps that just feel off and the limits on folders and filters.
ProtonMail only gives 1GB of storage and stuff like custom domains, aliases, etc are all paid features. The Android app is decent but missing some basic features that you only notice when you actually use it (select and delete when searching for example). Definitely the most robust mail service there is though. With Proton Unlimited, you also get stuff like per-site aliases using SimpleLogin, Proton VPN, Proton Drive, Proton Calendar and Proton Pass. But if I'm being honest, only the Mail and VPN are truly complete products.
I would recommend either Mailbox or Posteo simply because they cost 1€/m. For email I find that anything more than like $2 is a waste of money, but that is my opinion.
Both Tutanota and Protonmail offer freemium versions of their services.
I moved to Fastmail last year and it's been entirely unremarkable which is exactly what I want. Mail in and out works, it's reliable, I have my custom domains.
It really depends on the level of privacy you're going for and what features you want. For me I needed custom domain support with catchalls. The only other requirement I had was to not be Google. I debated between Fastmail and Proton for a while (Fastmail for features/price, Proton for the "better" privacy.) Ultimately I ended up on Fastmail because I would have had to pay for a higher than necessary account at Proton for what I wanted.
Paid Fastmail User here since around half a year. Did extensive research on what provider to use and trialed fastmail for four weeks before buying. I went for a 3 year period. Fastmail has a fantastic set of features.
There are providers that are focused more on privacy (e.g. PGP. encryption, not being based in Australia) but that was not my top priority.
I’ve been on Fastmail for several years and like it a lot! It lets you use you own domain name as well. Their app is not particularly great, but you can hook things up with the default iOS/Android/whatever mail app just fine.
Gotta go for ProtonMail. Have been running it for a year and I kinda like how it's doing.
An additional feature is SimpleLogin's "Hide My E-mail" Aliases, which are "burner" e-mail addresses to use with pre-determined SimpleLogin domains (you can add your own domains as well to go around Proton's custom domain limit). Those are included in the full suite and Family subscriptions. (10 a month when subscribing for a year)
There's also a cheaper variant for 3.50 a month but it lacks the SimpleLogin feature. You can get SimpleLogin seperately for 30 a year, however.
I've been using Zoho mail for a few years now with my own domain linked to it and it works flawlessly for less than 12€/y. (less than 24€/y if you also add the domain cost)
I interacted with one of RMS's public emails last week (not sure if I talked to RMS directly or not) and it came from protonmail. That's about as good an endorsement as one can hope for, so that's where I plan to migrate to.
Fastmail is great and has very fast user interface and lots of nice features, such as email address aliases you can create with a button click or integrate it with Bitwarden etc.
It costs money though, just so you know if you want "free" (nothing is really free).
If you're moving your email address consider using a mail alias. If you move again in the future it will make the process a whole lot easier as you won't need to go to all your sites to update your email address. You only need to update the one email address with the alias provider.
Proton and Tutanota are the most privacy-focused ones, offering zero-access encryption. The flipside is that they are a bit more expensive and less easy to use with third party email clients.
There are a number of alternatives like mailbox.org, Posteo and Fastmail which are cheaper, and less private than the above two but arguably still better for privacy than Gmail (in that their whole business model isn't built off capturing and monetising your data).
Personally I use mailbox.org and have no complaints. I use it with third party clients like Thunderbird for desktop and FairEmail for Android so can't speak to how good their web UI is.
I also strongly recommend getting your own domain name to use with your email. It means if you ever want to switch providers in future you won't need to change your email address.
Another bump for Proton. My wife and I share an account with a few different addresses each going to their own folder. (One for me, one for her, one for shopping, one for spam, etc) Their VPN is great too and includes ad/tracker blocking.
Been steadily moving things over to Proton. Originally got it for the VPN, then eventually started to use it as a replacement for gmail when applicable.
Other people have mentioned Tutanota; as a user myself I can point out a few pros and cons:
Pro:
Extremely privacy focused - everything is encrypted and even they don't have access to your email content.
Pretty cheap for a pro subscription (although they recently changed prices and I'm not sure exactly what the new ones are like).
Pro subscription you can use custom domains and set up a few aliases.
Generally works fine.
Con:
Can only use their custom mail clients (in addition to the webmail interface), because they use their own encryption algorithm.
Tutanota is so extremely hardcore about security that it seems like a detriment to their user experience. I used to follow the Tutanota community on Reddit and there were so many posts from people who tried to sign up or access their email and were blocked, and they had to go through quite a process to get unblocked. I myself went through a period where I kept being unable to access my account on my phone and it turned out to be that they were blocking me because of "too many IPS connecting to my account from the same IP". I have 2 devices connecting - my PC and my phone, so apparently 2 devices is too dangerous for them. That happened 2 or 3 times for a few days to a week each time, but I haven't experienced it for a while now, though.
The user interface is not for everyone. I don't mind it myself, but I've seen a good number of people complain that it's too sparse and/or ugly.
Search is annoying - because everything is encrypted, emails can't be searched on the server side so the clients have to do the searching locally which requires building an index. If you happen to clear your storage you have to reindex everything again. It's also pretty slow and annoying to index further back than a few months.
You don't get much storage (like, only 1gb or something) and you have to pay to get more.
Overall, if privacy and control over your own email is important to you then Tutanota is a great choice. Just be aware that usability can be kind of a hassle.
When I was doing the same research a few years back Fastmail was recommended to me and I’ve been very happy with it. It was fairly easy to set up with an email address from my own domain too.
Check out posteo. It costs €1/month (you can pay more for extra aliases). Seems like a cool company, and you can use it with your own email apps (Thunderbird, K9, etc).
I use fastmail so I can easily use a desktop client and create aliases with bitwarden and it's a great service the only downside is it's not as private as proton mail, but I don't consider email private or secure
I'm using Posteo and have absolutely no problem with it. The base price is 1€/month and for my purposes I haven't needed to buy any extra stuff (like extra space or aliases). It also allows access via mail clients by IMAP and POP, which is something I've seen many popular gmail alternatives not providing, despite being IMO a pretty important feature.
You mentioned storage space is important for you. The default size is 2.0 GB, but you can acquire more by paying +0,25€/month for every extra gigabyte up to a maximum total of 20 GB.
It should be noted however that it is a German company and therefore has to comply with German laws.
The one thing I'm not really convinced by is their approach to spam. The web interface doesn't provide any way to define rules to filter out spam except for filter exceptions, but the service already filters out spam for you and it will never reach your inbox. I would normally think that's a bad idea, but I've never received any spam nor have I noticed any mail going missing (except for my lemmy.ml registration mail which I remember I had problems with but I don't remember if it was Posteo's fault and if yes if it was their spam filter in which case it could be allowed to reach your inbox by adding it as an exception).
It's pretty easy to setup your own domain if you don't mind it being someone else's server. I first used one called ZoHo, you just need a domain and a txt record to validate control as I recall and they'll do the rest for free. That was a number of years ago though so it may have changed since.
mailinabox gives you email, calendar, tasks, and nextcloud apps if you're willing to setup your own VPS and suffer through some setup, about $10-20/month
migadu.com, it's a Swiss company with servers in France (great privacy laws). You can host multiple domains and unlimited mailboxes on the same account, which starts at $20/year. They limit on numbers of emails sent/received (200/20/day on the smallest account) and on total account space (5 GB smallest), not on features. You can host multiple domains, multiple mailboxes, multiple aliases, individual login per mailbox, TLS connections, IMAP/SMTP/POP/webmail and all the features you can think of.
I don't know. I'm looking for a service that doesn't parse my emails or sell my data, has encryption at rest, allows custom domains with lots of email aliases,and crucially has imap/smtp access. I would pay up to $5 us/mo per box for this. Runbox seems okay but no encryption..
I understand that e2e encryption is basically not possible with imap and smtp, but I mostly just don't want every corporation and government in the world getting easy access to my data. I'm not doing anything shifty really, I'm just tired of being a product.
One important thing to take note of is: "Once your personal database has seen more than 200 spam and 200 non-spam emails, we automatically start using it to filter your incoming mail." This means, before you have received 200 spam emails (or marked them as such), the filter is going to perform significantly worse.
Personally, initially it was pretty bad compared to Gmail. However, it significantly improved over time. One thing that helps are masked emails (fantastic) - an email you can create, or is even created automatically for you, and then enter at dubious websites. If you get spam, you can simply block the whole email or fine tune it.