I evaluated a few different services on cost, privacy, access, etc., about a year and a half ago and finally moved to Posteo. I have also been looking at this space once in a while. Almost all the services I looked at focused on privacy explicitly, with some being stronger than others.

I can talk more in detail about Posteo, while with the others I'll stop with what I know from my evaluation and checking on their sites later. The services I evaluated were:

1. Posteo (posteo.de)

Pros:

* Cheap enough (could be cheaper), good privacy policies, has good help documentation on protecting privacy better, IMAP support.

* The company is highly focused on social good and social justice (this will be abundantly clear when reading through the website). This was another plus to make me switch.

Cons:

* Privacy wise, the location of the servers is a fourteen eyes country — Germany.

* No custom domains (this could be a pro, depending on one's outlook; as far as Posteo is concerned, this is a pro because Posteo tries hard to avoid collecting any kind of information that could tie an account to you as a person).

* Support is slow to respond.

* No spam folder, since spammy mails are rejected by the server before they even come to the mailbox. Side effect is that mails from authentic senders may bounce, and Posteo support may just report that nothing is wrong on its end after a few days. Posteo retains logs only for seven days. This makes inbound deliverability related troubleshooting highly difficult to handle.

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2. Mailbox.org

Pros:

* Cheap enough, and slightly similar to Posteo in pricing, IMAP support.

* Custom domain support.

* Provides a cloud office system on the web.

Cons:

* Privacy wise, the location of the servers is a fourteen eyes country — Germany.

* The pricing is in tiers, and not more like a proportionally scaled payasyougo kind that Posteo has.

Documentation could be improved. Linking a custom domain is a bit tedious to do if one follows the documentation.

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3. ProtonMail (protonmail.ch)

Pros:

* Custom domains.

Cons:

* Privacy wise, the location of the servers is Switzerland (not a 5 eyes, 9 eyes or 14 eyes country).

* Pricing is expensive compared to Posteo or Mailbox if you need multiple mailboxes (and not just one mailbox with multiple aliases).

* A bit painful to move out of ProtonMail because the main options to access email are to use webmail or mobile apps. For more than two years, there was no IMAP support to mass download and keep a copy of emails. Recently an application called ProtonMail Bridge has been made available that will act as an IMAP/SMTP gateway to your email client. This means that there is still no direct IMAP access, and accessing mail using a client like Thunderbird requires installation of the ProtonMail Bridge (available on Windows and macOS).

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4. Tutanota (tutanota.com)

Pros:

* Custom domains.

Cons:

* Privacy wise, the location of the servers is a fourteen eyes country — Germany.

* Pricing is slightly similar to Posteo and Mailbox, but not as granular as those services. So when your needs grow, you may end up paying for a lot more, comparatively.

* Painful to move out of Tutanota since there is no support for IMAP/POP. Such support won't be coming in the near future either.

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5. Fastmail (fastmail.com)

Pros:

* Custom domains.

* IMAP support.

Cons:

* Privacy wise, the location of the servers is a five eyes country — USA.

* Pricing is expensive compared to Posteo or Mailbox if you need multiple mailboxes (and not just one mailbox with multiple aliases).

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6. Migadu (migadu.com)

Pros:

* Very cheap (or the cheapest) if you need multiple mailboxes since pricing is not based on that. If you need four mailboxes or more, none of the others can beat this one on price.

* Custom domains.

* IMAP support.

Cons:

* Privacy wise, the location of the servers is Switzerland (not a 5 eyes, 9 eyes or 14 eyes country).

* Privacy part is just ok. Could be a lot better.

* Most parts of the website were updated in September 2016. The copyright messages were also outdated, standing at 2016 till early this year. Doesn't look like anyone maintains the site regularly.

* Currently the site doesn't even load on the browser (confirmed as a multi-location problem through other services).