How the canadian postal code system works? Hi, I would like someone to give me some clarification about the canadian postal system. I have to send a book to someone in Canada and I'm a little bit confused about how to write the address. I'm going to buy the book from a website called bookdepository, when I try to enter the address it asks the zip code, but I'm not sure what to put. My friend sent me his address that is something like this: 8221 McWhatever Ave, Ottawa, ON J9F 9c3 , Canada (This is not the real address). My question is, what's is the postal or zip code? In Brazil we use only numbers :)