As more online services begin detecting and blocking email addresses associated with forwarding or masking services (e.g., those using generic alias domains like passmail), it would be highly beneficial if Proton Mail allowed users to create aliases that end with their own custom domain—for example, amazon0110@mydomain.com.

This feature would help maintain the privacy and organizational benefits of aliases while significantly improving compatibility with services that currently flag or block addresses from known alias providers. While this isn't a widespread issue yet, early signs—such as registration restrictions from services like Cursor—indicate this will likely become a more prominent barrier in the near future. Supporting custom domain aliases would future-proof Proton Mail’s alias system and give users greater flexibility and control over their digital identity.

It is already possible and include in proton pass paid user with SimpleLogin

I signed up for protonmail ultimate hoping to use the unlimited hide-my-email aliases, but was disappointed after attaching my custom domain that I couldn't then use it in the alias generator (either the one build into proton mail, or the proton pass one which are the same). I might be able to inconveniently add a subdomain to simplelogin, but it would be really inconveniant compared to the protonmail/protonpass integration.

+1
I don't see a compelling reason to use ProtonMail until this is implemented.

+1
I think the "unlimited" plan should have "unlimited" aliases. I don't like subaddresssing with +, because some sites don't handle them well, and it's easily detectable.
Ideally, I'd use one alias for each site I register to (banks, school, gaming accounts, etc).

I have a custom domain for ProtonMail and would like to use it to create my aliases in Proton Pass.
I do not want to configure another service (SimpleLogin) for this purpose !

You need to add your domain to SimpleLogin, since ProtonMail itself doesn't provide alias functionality.
Then you can use the domain is PP too.

With the growing popularity of Proton Pass and Hide Me, more systems will detect and block hide-me domains. To bypass this, offer the option to create an alias using my own domain.

It's one of the two showstoppers that prevent me from switching from Google Workspaces to Proton. My family is taking full advantage of multiple aliases for segregation of concerns (school, finance, etc) and I see no reason why they should be limited on a high tier account.

Another +3. One of the biggest features I am missing after moving from Fastmail. I don't see from a technical standpoint why removing this limit shouldn't be possible.

+3. Limiting and paying for aliases on Proton domains makes perfect sense. It makes absolutely no sense to have the same limits imposed on our own domains which we control. The storage space is paid for and shared between the mail boxes, it's not like they each have a separate allocation.

Please lift this arbitrary limitation.

It would be great if we could create email aliases using our custom domain directly through ProtonPass. I know this can be done via SimpleLogin, but thinking about a family plan where a spouse or children would use the service, it's complicated to deal with privacy education by asking them to use one portal to create emails and another to create and manage passwords and logins. Even for personal use, it's much simpler and faster to create aliases through ProtonPass directly via the app or extension.

Along with this, it would also be great if each family member could create their own aliases on their accounts using the custom domain of the family owner and each receive their emails related to their created aliases.

It would be great if we could create email aliases using our custom domain directly through ProtonPass. I know this can be done via SimpleLogin, but thinking about a family plan where a spouse or children would use the service, it's complicated to deal with privacy education by asking them to use one portal to create emails and another to create and manage passwords and logins. Even for personal use, it's much simpler and faster to create aliases through ProtonPass directly via the app or extension.

Along with this, it would also be great if each family member could create their own aliases on their accounts using the custom domain of the family owner and each receive their emails related to their created aliases.

Same request for me.

Today, I subscribed to ProtonMail. Immediately after subscribing, I realized that the limit of only 10 aliases for my custom domain is insufficient for my needs. I am not a fan of the catch-all feature, as it results in receiving emails like '{random}@mydomain.com.' Instead, I prefer to disable the catch-all feature and create a separate alias for each specific use case, ensuring that I do not receive spam under my domain.

While I am aware that SimpleLogin can fulfill this requirement, the challenge lies in configuring my domain on two systems simultaneously.

I kindly request ProtonMail to consider providing unlimited aliases for custom domains.

My Proton plan supports 3 custom domains but only 15 email aliases. I need many more custom domain email aliases in order to assign one email address per online account and retain the ability to reply to incoming messages.

I have been a paid Proton customer for several years now and being limited to the number of aliases I am allowed to create under my own domain has always been a serious problem for me as well. While restricting the number of aliases customers can create under Proton's domains makes sense I do not understand why we have not been permitted unlimited aliases under our "own domains" registered with Proton. I am aware of the SimpleLogin aliases Proton now provides, but this is not the same thing nor does it allow seamlessly replying to email received through it. Hopefully, Proton will permit paid customers unlimited email aliases soon, this would benefit many customers allowing us to be more productive while having some more functionality with more privacy. Thank you for your consideration.

+1 for unlimited domains/aliases

Yeah, there are already some websites that have blocked @passinbox.com and @passfwd.com. Would be great to have any solution for this problem!

There are some sites that do not allow using aliases from proton. I want to be able to add my own domains that could be used not only in proton mail, but also in aliases.