On July 1, 2004, Seoul opened a new chapter in the public transportation, aiming to achieve a transit system that is both faster and more convenient. To reduce confusion and simplify passenger use, each bus in the municipal transit system will now employ one of four colors: blue, green, red or yellow, depending on its function. Now, passengers can easily identify the starting point and the destination of a bus at a single glance. The entire area of Seoul is divided into eight zones, which are clearly indicated in the numerical designation of each bus.
To search for Seoul public bus routes, go to (http://english.seoul.go.kr/images/SeoulBusMap.pdf)
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Blue buses (Main Line) serve the major trunk roads between downtown Seoul and satellite cities of Seoul. The buses have the letter "B" on them, representing blue buses. Bus numbers have 3 digits. (Example: 141) |
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Green buses (Branch Line) serve routes between subway stations and nearby residential areas/main bus lines. (These routes are often covered by village buses) The buses have the letter "G" on them, representing green buses. Bus numbers have 4 digits, starting with "9." (Example: 2412) |
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Red buses (Wide Area Line) serve routes between major areas (downtown, Gangnam, Yeongdeungpo, etc.) and metropolitan satellite cities (Ilsan, Bundang, Uijeongbu, etc.). The buses have the letter "R" on them, representing red buses.
Bus numbers have 4 digits. (Example: 9412)
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Yellow buses (Circular Line) serve circular belt roads in the downtown and major metropolitan area. The buses have the letter "Y" on them, representing yellow buses. Bus numbers have 2 digits. (Example: 41) |
Pictures provided by Seoul city.
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Bus Numbering System |
Zone number division map for bus route system | 
