I agree with a lot of the other options, but I'd be remiss if I didn't mention one that isn't always obvious.

With all the Big Corp asterisks, Microsoft Business Basic can be a pretty great deal at 6 USD/month. Solid reliability, aliases, (too many) config options, 1TB of OneDrive storage, cloud MS apps, etc.

Fastmail has been solid for the last several years. I would recommend it.

Also a happy fastmail paying customer. The aliases are really good.

Fastmail is just about perfect. Feels like email 30 years ago but with a spam filter.

You can also use gmail with a custom domain. Helps with not being locked in to Google, doesn't of course help in them selling your data.

E.g. https://juri.dev/notes/email-routing-gmail-cloudflare/

If you need something cheap and are willing to deal with a tiny company, have a look at <https://purelymail.com>. I've been happy with them for two years, never had any problems with delivery, and they support infinite domains/aliases, and custom Sieve rules. But do not use it if you need 99.999999% SLAs or anything like that, because again -- it's a one-man show.

Fastmail

Proton mail

i really, really like purelymail. great pricing, good customer service, reliability, and documentation.

other popular options are fastmail, migadu, and mxroute.

I've used Fast Mail, liked it a lot, but I think at the time the pricing wasn't the best.

I then used some other platform that was quite "old school" that is recommended here. The Mail Admin was very opinionated which lead to some mail being blocked. That wasn't cool.

I'm now with Migadu on the cheapest plan and it's been fine. Had a few outages here and there, but otherwise solid.

I'd happily rec Fastmail or Migadu.

Apple hosts custom domains at no extra charge if you have iCloud+. I've used it for a couple years now to host my family's domain and a couple of hobby ones for myself.

I would probably still be on Apple mail and use its generated email aliases except it went through a stage of not dealing with various back bounce spam so I switched to fastmail and have had no issues.

Either now is probably a good choice.

uberspace because of SSH access

Zoho Mail. Cheapest, no nonsense, very straightforward UI, all the settings you'd ever wish for, support replies quickly even on the cheapest tier.

Migadu