Apple Private Relay Subscribers: What is this?

Okay, you've got subscribers on your list from the domain "privaterelay.appleid.com" on your email list and you're not sure what this is. And when you try to send your email campaign to those subscribers, it always bounces back! What gives?

Here's the dealio yo! These addresses in the "privaterelay.appleid.com" email subdomain are legitimately handed over to a sender whenever a potential subscriber registers for your account or email list by way of the "Sign in with Apple" functionality, with "Hide My Email" setting enabled.

To be able to send to these addresses, you need to register your sending domains with Apple.

Theoretically, your company has an Apple developer account already, because that was necessary to be able to implement the "Sign in with Apple" widget in your website or application.

But in some cases, you might not actually be set up with "Sign in with Apple." If you're getting "privaterelay.appleid.com" subscribers on your list and it's NOT because of the Apple process, then something has gone horribly wrong. Believe it or not, there are bots that go around submitting random email addresses to web forms. Why? I can only guess. Maybe it's a spammer trying to verify the validity of an email address before sending spam to it. Maybe it's a griefer just trying to cause you trouble by loading your list up with addresses belonging to people who didn't actually want your mail. Unfortunately, regardless of the reason, it happens.

If you're getting "privaterelay.appleid.com" addresses submitted to your web forms or online registration, throw them out. They're not legit. And implement CAPTCHA, because somebody's intentionally feeding garbage to your signup process. It happens to pretty much everyone – even here, with my tiny little email newsletter of just under 1300 people, whenever I disable CAPTCHA, somebody tries to feed garbage to my signup form again.

There's no data sharing or list purchasing of "privaterelay.appleid.com" email addresses. They're unique aliases, given to specific senders. I don't know if Apple can block address misuse as the gateway, but I wouldn't want to find out what happens when and if Apple notices that a sender is misusing those addresses by sharing them with others. Getting locked out of the Apple email ecosystem can't be a good way to further your email marketing efforts.

But couldn't an Apple subscriber manually give me a masked/hidden email address at the point of email capture? Yes, but. It is indeed possible for Apple users to create unique email aliases, but those "hand made" ones are of the format "averse_exurban_02@icloud.com." Meaning, these particular email aliases are addresses that anybody can send to, at the usual iCloud main email domain. There's no "private relay" issues associated with sending email here. (Apple takes care of the potential authentication issues associated with email forwarding, in case you're wondering.)

Want to learn more about Apple address masking? Here's an explainer on the differences between private relay (the web service), private relay (email) and hide my email.