> his lease said that he wasn't allowed to receive mail at the house he was legally renting.

Pretty sure that is not a stipulation you can legally put in a tenancy contract. Because both parties have to be able to serve notice on the other via post in writing. Same reason you are legally entitled to know the postal address of the landlord.

I'm sure you are right, but that didn't stop the landlord from trying their luck. Your observation about serving notice is on point, because in the end the deposit was returned only after my friend filed a small claims case against them.

> I have no idea what “mail” is

Not a native speaker. How do you refer to the pieces of paper that the Royal Mail sometimes drop through your letterbox?

Ironically, despite the company being called the Royal Mail, the letters it delivers are referred to as "post".

This is unlike the US Postal Service, which delivers "mail".

Interesting! Thanks.

To be clear, mail and post are the same thing, one is US English and the other UK English, though as you can see from the names of the companies involved, the distinction was not always so clear cut.

The comment claiming not to know what "mail" was clearly struck people as a little dismissive of US English (any native English speaker knows both "mail" and "post", regardless of which one is used locally)