As others pointed out, this is actually not completed and the status should probably be updated to reflect that.

Multiple USERS under the same account can share a custom domain, however this feature does not work for separate ACCOUNTS.

This is a must have feature - and there are a number of scenarios where it is desirable to keep to accounts and billing separate, while still being able to share the same custom domain.

Proton currently supports custom domains, and it supports sharing a custom domain among different users of an account or organization.

However, if you have separate accounts, it is impossible to share a custom domain among them.

An example where this becomes problematic is a Visionary subscriber; they can add addresses / users / sub-accounts, but CANNOT share ANY of those domains with anyone that ALREADY has a Proton account.

Those people would then have to needlessly juggle multiple separate accounts, lowering the probability that they would bother.

Please enable support for sharing domains across accounts!!

How about try and set up two accounts on two different subdomains? E.g. mail@king.example.com and mail@queen.example.com.

When using a custom domain and having multiuser support, I need the ability to add a protonmail.com domain to my users so they have both the custom domain and the protonmail domain (just like the primary account). This allows consolidation of personal email and professional email to one account.

Its still not possible for two separate Plus accounts to use the same domain like Cristian states. Like many others have commented here I also want Me and the wife would like to have separate accounts but using the same domain

Nathan is absolutely right. There is a big gap in price table. It is not fitted for family case. I've upgraded to PLUS for that feature :-( You have to change plan description.

It looks like it still is not possible to use one domain with two separate ProtonMail Plus accounts (wife and myself). The error the second account gets is: Domain setup failed or domain is already in use within ProtonMail
I think this case comes up quite a bit for families and not "Professional" Accounts...

Agreed. I want 1 custom domain for two users (my wife and I). It looks like we could get two custom domains (presumably different) for two users for 2x$48/year = $96/year (separate Plus accounts) rather than one Professional account with two users for $150/year. I don't get it; it looks like proton mail isn't interested in supporting the family use case. I love my free experience so far, let me know when you're interested in taking my money by offering the configuration everyone is asking for on this thread.

It's a shame Protonmail still does not support multiple ACCOUNTS using the same custom domain. Not sub-users, but ACCOUNTS. Why is an integrated approach using the protonmail.com domain for existing users not already available?

Sad to say to have a husband and wife account is just too expensive at the cheapest price possible its $258 every 2 years. Dear ProtonMail I have supporter before this service ever existed when I funded the Kickstarter effort a few years back. As it stands I have to by two plus accounts which at the 2-year price for 2 accounts is $148. Certainly don't need the Professional plan as it is aimed at business which we are not. Sorry I will not upgrade to professional, it's not economically justifiable for only 2 users. And since you already have the ability to do multiple accounts having the PLUS to have just 2 accounts would bring in more money to further product development with little development cost. As a professional software developer for businesses I know this to be true.

The wording should indeed be: "Aliases" not "Addresses". I sure got my hopes up for short amount of time :) But the per Mailbox price of 6.25 a month is pretty steep for a family I have to say.

Too expensive for non-business users

I was hoping for something less pricey for a couple for example :-/ at 6.25€/user, my wife says no :(

Is this feature live?

Has this feature been released?

Would you please make it clear for me, if under professional plan is it possible to have two different domains and several users on each domain. Let's say:
user-one@domain-AA.com, user-two@domain-AA.com
user-three@domain-BB.com, user-four@domain-BB.com

Thanks.

The pricing for multiple users on the same domain has been changed today with the new professional plans in v3.10. Here a listing of the cheapest plans for 'n' users under the same domain:

1 user: 48$/year (PLUS subscription)
2 users: 150$/year (PROFESSIONAL subscription)
3 users: 225$/year (PROFESSIONAL subscription)
4 users: 288$/year (VISIONARY subscription)
5 users: 288$/year (VISIONARY subscription)
6 users and more: 75$/user/year (PROFESSIONAL subscription)

Those are hefty prices. But programmers aren't cheap - especially in Geneva, one of the most expensive cities in the world. Custom domains are a premium feature, if you con't afford it there is always the free plan.

Holla, any news ?
Is this feature already implmented ?

After one year, I just renewed for one month since there is no improvement on this topic. To help me to decide could please tell us if the feature will be available for the "plus" users or if your solution is to upgrade to visionary.

I've a ProtonMail Plus account, but I need a second separate email address for my wife configured with our own domain. You'll understand the gap (price) between plus and visionary is too big...

Please tell us the feature is comming. As @protonmailteam says the feature is under construction. Please give us a feedback.