The domain search feature on haveibeenpwned is/was free. I registered my domain on haveibeenpwned back in 2017 and I got two emails about breaches, one in 2020 and another in 2022. I did not pay.
It tells you that an address in your domain has been included in a breach. It doesn't tell you which address was included. That's what the OP and I are opining about.
It does. I just checked mine today. I can see exactly which individual email addresses in my domain where exposed and in which data leak. I have never paid for it.
Interesting. I'd love to see where you're seeing that. I'll go poke at the site a little more.
Edit: When I try to do a domain search I get told:
> Domain search restricted: You don't have an active subscription so you're limited to searching domains with up to 10 breached addresses (excluding addresses in spam lists).
Yep, if you have the good fortune of having many breaches while using companname@example.org, the service requires that either you pay up or you have to guess and check.