Postal Code Day

What Is Postal Code Day?

July 1st is Postal Code Day in Japan, commemorating the launch of Japan's postal code system on July 1, 1968. Introduced to streamline the sorting and delivery of mail during Japan's high economic growth era, the system has since become one of the fundamental pillars of the country's logistics infrastructure.

History of Japan's Postal Code System

• July 1, 1968: The postal code system officially launched with 3- or 5-digit codes
• February 2, 1998: Japan transitioned to the current 7-digit format (3 digits + 4 digits)
• Today: Postal codes are used not only to sort mail but also to auto-fill addresses on websites

How Japan's Postal Codes Work

Japan's 7-digit codes are divided into a 3-digit area code and a 4-digit district code. The first 3 digits broadly indicate the area; for example, codes from 100 to 208 belong to Tokyo.

Fascinating Facts About Postal Codes

• The "〒" symbol: Japan's unique postal symbol derives from the first letter ("Te") of "Teishin-sho" (Ministry of Communications), and is said to have been adopted as the postal mark in the Meiji era
• OCR (Optical Character Recognition): Sorting machines automatically read postal codes — even handwritten ones — with high accuracy
• Address auto-fill: When you type a postal code on an online shopping site and your address fills in automatically, that feature is powered by a postal code database
• Global comparison: The U.S. uses 5-digit ZIP codes; the U.K. uses alphanumeric postcodes; Germany uses 5-digit codes

How to Observe Postal Code Day

• Look up the origin of your own postal code and explore the numbering logic of your neighborhood
• Send a handwritten postcard to someone you haven't contacted in a while — in the age of digital communication, the warmth of analog mail shines all the brighter

Seven Digits That Connect the Nation

Millions of pieces of mail arrive at their destinations every single day, and behind that seamless flow lies the simple but elegant system of postal codes, built up over more than half a century since 1968. The next time you write an address, spare a moment to appreciate the history encoded in those seven digits.