LetterAgent
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Home > Guides > Addressing a Letter to Japan
LetterAgent cannot mail a letter to Japan, because its recipients must have a United States or Canadian address, but a Japanese address written in romaji for international mail runs in reverse of a Western address: postcode first, then prefecture, city, ward, district, block, building, and name last.
Japanese addresses run from the largest unit down to the smallest: prefecture, city, ward, district, block, and finally building and room. That is the opposite of a Western address, which starts with the person and narrows down. For mail sent from abroad, you write the address in romaji (Japanese words spelled with the Roman alphabet) and keep the Japanese order, then add JAPAN in capitals on the last line. Japanese postal workers read romaji addresses every day, so you do not need to write in Japanese characters, though including them alongside the romaji can help if you can copy them exactly.
| Order | Element | Example |
|---|---|---|
| 1 | Postcode (7 digits, with a hyphen) | 150-0002 |
| 2 | Prefecture and city | Tokyo-to, Shibuya-ku |
| 3 | District, block, building numbers | Shibuya 2-21-1 |
| 4 | Building and room (if any) | Shibuya Building 301 |
| 5 | Recipient name | Yuki Tanaka |
| 6 | Destination country, in capitals | JAPAN |
Japanese postcodes have seven digits, written as three digits, a hyphen, and four digits, like 150-0002. The hyphen matters: it splits the code into the regional part and the local part, and sorting systems expect it. The block number after the district name also uses hyphens, in a chain like 2-21-1: district block 2, building 21, and sometimes a sub-number 1. Do not turn these into a street number and street name. Japan largely has no named streets in addresses outside a few famous ones, so the block system is the address. If you drop a hyphen or a digit, the letter can land in a different block of the same district.
Japan has 47 prefectures, the top-level regions: Tokyo-to, Osaka-fu, Kyoto-fu, Hokkaido, and 43 ken, all of which work the same way in an address. Large cities split into wards (ku): Tokyo's Shibuya-ku is one ward of the city, not a separate city. Below the ward comes the district (machi or cho), then the block (chome). Write each element in full where you can: "Shibuya-ku" rather than just "Shibuya," since the ward suffix tells the sorter it is a ward. For a rural address, the pattern shifts slightly: prefecture, county (gun), town (machi), and then block numbers, with no ward at all.
For international mail, write the name in the Western order (first name, then family name) in romaji, since that is how a foreign sender would know it and how the recipient will expect it on foreign mail. Inside Japan, family name comes first, so if the recipient gives you their name in Japanese order, keep it exactly as they gave it rather than flipping it. Add a title only if you know it: "Mr.," "Ms.," or the Japanese honorific "sama" after the name for formal mail. Do not add "san" to your own name on the return address: it is a courtesy title for other people, not for yourself.
Put your return address in the top left corner, in your own country's format, with your country name in capitals on its last line. If your post office offers an airmail marking, add it: surface mail to Japan takes far longer, and the marking keeps the letter in the air stream. Write the whole destination block in clear block capitals in romaji, and double-check every hyphen and digit before sealing the envelope. One wrong digit in a Japanese postcode can send a letter to a different prefecture, not just a different street.
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