To prepare for the opening of the Circle Line Stage 6 (CCL6) in the first half of 2026, which will close the loop for the Circle Line by connecting HarbourFront station to Marina Bay station, LTA and SMRT will carry out a series of works on the existing CCL to renew its Integrated Supervisory Control System (ISCS). This is to ensure system compatibility with the new stretch of the Circle Line.

To facilitate these works, from 15 June to 30 July 2025, CCL train services will end earlier at 11.00pm from Sundays to Wednesdays. Services on Thursdays, Fridays and Saturdays will remain unchanged. For more information on affected dates and adjustments to services, please refer to Annex A. 

Need for Service Adjustment 

The ISCS monitors and manages the systems on the CCL, including power supply, communications and station facilities. It also supports communications between stations, control centres and trains. The current system has been in use since the CCL began operations in 2009, and needs to be renewed to ensure it is compatible with the new CCL6 system. The service adjustments are required to provide longer blocks of engineering hours necessary for testing and commissioning of the new servers and equipment to be carried out safely and rigorously. 

Commuters are advised to plan their journeys in advance and rely on alternative routes via other MRT lines and bus services to reach their destinations. They can also refer to LTA’s MyTransport.SG mobile app and LTA’s and SMRT’s social media platforms for more details. Posters will be put up at all CCL MRT stations and at stations that interchange with the CCL to alert commuters to the service adjustments. Station staff will also be deployed at affected stations to provide assistance during the service adjustment period.

Future Service Adjustments on the CCL  

Further service adjustments will be needed to complete systems integration testing across the entire CCL, and ensure that the CCL6 stretch is well integrated with the existing CCL. At present, we plan tentatively to carry out these adjustments from September to December 2025. More details on the future service adjustments will be provided closer to the date.

We seek commuters’ understanding and patience during this period. These temporary service adjustments are necessary as we prepare for the opening of CCL6, so that there is sufficient time to conduct thorough and rigorous testing to ensure the safety of our commuters. These works will bring us closer to the completion of the CCL6 extension, which will enhance connectivity, shorten travel times, and bring greater convenience to our commuters.