I know you specifically requested a free service but if you can spare 1€ a month for it, I highly recommend mailbox.org

I have had it for more than a decade and just switched away. Apparently a lot of spam is sent through them, so I had an issue where an email I sent bounced back. Also their incoming spam filter is bad causing me a five-day delay on one important business email. They also have ads which I don’t really mind since I use adblock anyway. The mailbox cannot be set in new outlook and all automatic filters are quite primitive to set. I haven’t seen any updates at all to it in the decade either, so wouldn’t be surprised if it had a ton of security vulnerabilities. I didn’t know they offer any paid services.

Some relatives still have it, it’s filled to the brim with advertisements which i guess if the catch. I mean the web interface is, you don’t have it when using imap of course. It’s still a dealbreaker for me.

I’ve just switched to posteo , they are located in Berlin, Everything seems to work well, but they cost (a minimum of) one euro a month - what I liked was that It is easy to scale up, and they appear to be very ecology conscious. Ad free, located in Berlin.

Former admin here, ama.

Can only report positive things from the inside, good people with moral compass there, not a thing I say often. Mail.com is also owned by the company.

Of course it's often tried to get you to pay more by pushing you to subscribe pro features.

If the service is free, then you are the product. Just pay for mail. Someone here mentioned Posteo. I use Soverin.net. It costs peanuts. Also, make sure you get your own domain name. It makes migrating email to a different provider trivial. It's really worth the 10 or so Euro per year.

I had an account a long time ago, it was very good. They unfortunately deprecated the UI translations, so everything went German only, which was painful to navigate.