Jeju's official system says transit card holders may receive up to two transfer discounts within 40 minutes of tapping off a bus. Changing between regular routes differs from changing to an express or airport limousine, which may carry an extra charge. Tourist loop buses use the local fare category. Prepaid cards such as T-money and Cashbee work, but youth discounts require age registration with the card provider. Paying for multiple passengers on one card does not provide equivalent multi-person transfer discounts. Always tap out and check the next bus type.