T-money

T-money is a rechargeable series of smart cards and other "smart" devices used for paying transportation fares in and around Seoul and other areas of South Korea. T-money can also be used in lieu of cash or credit cards in some convenience stores and other businesses. The T-money System has been implemented and is being operated by T-money Co., Ltd of which 34.4% owned by Seoul Special City Government, 31.85% owned by LG CNS, and 15.73% owned by Credit Card Union.
Usage.
Similar to its predecessor, the "Seoul Bus Card", T-money can be used to pay for bus, subway and some taxi fares. As of March 2017, T-money is accepted by:
Some stores and attractions including Seoul's four palaces (except Gyeonghuigung), Lotte World amusement park, Kyobo Book Centre, GS 25, CU/FamilyMart and other selected convenience stores accept T-money as payment method.
Card types.
Standard.
T-money cards cost 2,500 - 4,000 won and can be purchased and recharged at metro stations, bank ATMs, convenience stores and kiosks located adjacent to bus stops. Self-service recharge machines are also available at Seoul and Busan metro stations.
In 2014, "One Card All Pass"-enabled T-money was introduced. It holds "One Card All Pass" logo, and bears slightly different card number system compared to generic T-money. As of March 2016, "One Card All Pass" T-money is accepted at major retailers, most express bus and some intercity bus routes, express road toll booth, Korail railroad station, all metro system, and all bus system except Gimhae.
Discount cards.
There are two types of discount cards available for sale, one for teenagers (age 13-18) and the other for children (age 7-12). One needs a proper ID such as a Youth Card or Student ID in order to purchase these cards. Discount cards must be registered via the Internet within 10 days after first use. Registration requires the number on the card, and a National ID number or Foreigner registration number, or, there is a form available on the t-money website (under English Errors) that can be emailed to customer service along with supporting documentation. Senior citizens are entitled to free transportation and can pick up free tickets at ticket machine in Seoul metropolitan subway stations with proper ID.
T-money accessories.
Smaller, more durable T-money cards with a lanyard for easy attachment to cell phones are also available, for about 6,000~8,000 won. Watches, dolls, MP3 players, portable memory sticks, rings and bands containing T-money chips are also on sale.