In order to alleviate traffic congestion by vitalizing the use of public transport and reducing the use of private cars, congestion tolls are charged to vehicles passing the Namsan 1st and 3rd Tunnel. Since November 11, 1996, SFC has been implementing the congestion toll program.

The congestion toll charged at the Namsan 1st and 3rd Tunnel aims to remove traffic jam in the downtown area by reducing the use of private cars and vitalizing the use of public transport. The hours of toll charge is from 7a.m. to 9p.m. for any vehicle with less than 2 persons including a driver.

According to the revision made in the Ordinances of Congestion Toll Charge in Seoul Metropolitan City in April 1, 2001, the target vehicles for toll charge were expanded to a private car and van that is less than 10-seater. From July 25, 2003, 50% of the congestion toll was reduced for a compact car in accordance with Automobile Management Act and the same was applied to Low Emission Vehicle with an electronic tag and self-car free program participating vehicles from January 19, 2007.