Is it possible to send an anonymous letter?

Question

So, I'm sending my best friend(guy) a letter. And, I kind of don't want him to know it's me at first. Sort of like a riddle so, is it possible if I just write his information and then where you put the return address just my initials? Or will that not work?

Answer 1

You don't need to put any return address on the envelope if you don't want too. The post office will still deliver it to your friend,

Answer 2

Well, yes you can do send an anonymous letter.

He may not figure out that you are the sender, though.

All the best.