This is just a quick note to help simplify the Japanese postal address system. It’s different from the system used in the US and many other countries but once you understand the theory, it’s really not that confusing.
Interestingly enough, there are several common phrases in Japanese which combine simple words in the exact opposite order from English: “white-and-black” instead of “black-and-white”, “right-and-left” instead of “left-and-right”, “out-and-in” instead of “in-and-out” just to name a few. Japanese addresses are also reversed from what you may be used to in English. For example, a typical US address would start with the name of the person or company, then the street address, followed by the city and state, and then the ZIP code (and finally the country, if you’re talking about an international parcel or letter). A Japanese address starts with the postal code. Then you list the prefecture and the city, in that order. Finally the name of the person or company at the end.
If you think about it, the Japanese system makes sense. The first thing a postal employee needs to know to deliver the item is the general area where it’s headed and that is represented by the postal code. They really don’t care about the receipent until the item ends up in the hands of the local letter carrier. So the information in a Japanese address is listed in the order it’s needed for delivery. Of course, US postal employees have long since learned to read the addresses from the bottom up but it does make one wonder why it’s written that way in the first place.
Japan is divided into 47 prefectures. Technically, it’s 43 prefectures (-ken), one metropolis (-to), two urban prefectures (-fu), and one island territory (-do) but when referred to collectively in English, the word prefecture is used (at least by Wikipedia). Each prefecture is divided into some number of “cities” (which may or may not be actual cities in the urban sense). There are many suffixes used for these cities in Japanese but you can almost always just add the name of the city immediately after the name of the prefecture.
From there, things vary by area. Since I’m most familiar with the scheme used in Tokyo, I will describe that in more detail. Other cities and urban areas work on the same general principle but the divisions may vary depending on local conditions (obviously a rural farming area doesn’t need quite as complex a scheme as Tokyo).
Tokyo is divided into 23 wards (-ku) and a number of other municipalities (-shi), each of which is fairly autonomous, much like a county in the US. Each ward and municiplity is divided into a number of named areas (with various suffices). The address progresses like the layers of an onion: after the prefecture and the city, you would add the name of the ward or municipality, followed by the name of the area. That’s the general pattern. Less populous areas might have one less layer to their onion than the wards inside of Tokyo but the onion principle stands.
So far, this may not seem different at all, save that there are more layers than you might find in most other places. But the big difference happens when you get to the granularity of the street address. The vast majority of the streets in Japan don’t have names (and those that do are never used in addresses). Instead, the onion pattern continues all the way down to the individual building. Each area within a ward or municipality will be divided into several numbered sections (-chome). Each block in one of these numbered sections is itself given a number and each building on the block is numbered, usually in the order they were constructed. So a typical “street address” might be something like:
108-0075 Tokyo-to, Minato-ku, Honan 2-16-3, Shinagawa Grand Central Tower, Microsoft Corporation, Japan.
The first set of numbers is the postal code. Tokyo is large enough to be considered a prefecture in its own right so that comes next. Then the name of the ward. Then the name of the area (in this case, the second “chome” of the Honan area). Then the block number (16) followed by the number of the building within that block (3). The building name is optional but helpful in case one of the numbers in the address is incorrect (yes… unlike in the US, if the postal carrier can identify the receipent despite an errant address, the item will often be delivered anyway).
This system explains the prevalence of maps in Japan. Just about every web site or advertisement for a shop or business will include a small map. There are neighborhood maps posted around train stations and at major intersections. There are also map applications that you can use on your computer or smartphone. And if you get lost, there are many police boxes (koban) where you can ask directions. They always have a very detailed map of the area you can refer to.
Some may argue that this is an antiquated system that only confuses residents but I’m not so sure. I’ve been in cities in both the US and Canada where even with a street address, you have no idea where a place is unless you’re from that area. It’s not at all unusual for streets that cross municipal boundaries to suddely take a huge jump in addresses right at the boundary and start decrementing when they were previously incrementing or vice-versa. Trying to find an unfamiliar place on a major street in Silicon Valley (California), for example, will drive you to drink and make you appreciate an onion-like model that pinpoints a location all the way down to a specific city block.