South Korea switched to five-digit postal codes in August 2015, replacing the older six-digit system. The new codes are based on the State Basic District system, so each code corresponds to a small, stable geographic area rather than to a delivery route.
Look up a postal code
Korea Post provides the official search by road-name address or by the older land-lot address. Road-name addresses are the standard format today.
Writing a Korean address
KIM MINJUN
123 SEJONG-DAERO, JUNG-GU
SEOUL 04524
REPUBLIC OF KOREAThe postal code follows the city name. Six-digit codes on old paperwork should be converted with the Korea Post search.
Not a U.S. ZIP
Korean codes look like U.S. ZIP codes but belong to a different system; the ZIP code lookup will return an unrelated U.S. place or nothing. See International postal codes.