The Land Transport Authority (LTA) and SMRT will complete the Circle Line (CCL) tunnel strengthening works ahead of schedule – by 10 April 2026, instead of 19 April 2026 as previously announced. With the completion of tunnel works, we will proceed with the final systems integration testing works in preparation for the opening of CCL6. CCL6 comprises, three new stations on the southern stretch of CCL and will close the circle of the CCL. To facilitate these testing works, train services on the CCL will be adjusted during the weekends from 11 April 2026 to 17 May 2026, with earlier closures on Saturday nights, and later openings on Sunday mornings.

Ongoing Tunnel Strengthening works

Since 17 January, LTA and SMRT have been carrying out tunnel strengthening works along the CCL from Mountbatten to Paya Lebar stations. As the teams involved gained familiarity with the complex work processes, they achieved some time savings, especially during the latter phases of works. Based on the latest progress, LTA has assessed that works can be completed about a week ahead of schedule. Train services will resume fully in both tunnels of the affected stretch on 10 April. With the resumption of normal CCL service, peak-period shuttle buses will operate at reduced frequency before ceasing operation after 13 April.

Upcoming Train Service Adjustments 

Following the completion of tunnel strengthening works, LTA and SMRT will proceed with the final phase of testing and commissioning works to integrate the CCL6 systems with the existing CCL network. This integration testing is necessary for the opening of CCL6. It can only be carried out after tunnel strengthening works are completed, as it requires the entire CCL to be available for testing.

To facilitate these works, train services for the entire CCL will end earlier on Saturday nights at 11.00pm and commence later on Sunday mornings at 9.00am, from 11 April to 17 May 2026. These service adjustments, similar to the arrangements from September to December 2025, will provide the necessary engineering hours needed for safe and rigorous testing and commissioning of the train systems. For more information on affected dates and adjustments to train services, please refer to Annex A.

During this period, we will provide shuttle bus services from 5.00am to 9.00am on Sundays. Commuters will pay the same fares for the shuttle buses as they would for train travel, and the routes and intervals are as follows:
 

• Shuttle 36 will operate between HarbourFront and Bishan stations, at intervals of 7 to 10 minutes.
• Shuttle 37 will operate between Bishan and Promenade stations, at intervals of 3 to 5 minutes.

Commuters may experience up to an additional 30 minutes of travel time during the service adjustments. Commuters are advised to plan their journeys in advance and consider alternative routes via other MRT lines and bus services. They can also refer to LTA’s MyTransport.SG mobile app and LTA’s and SMRT’s social media platforms for more details. Posters with information of the service adjustments will be displayed at all CCL MRT stations and at stations that interchange with the CCL. Station staff will also be deployed at affected stations to provide assistance during the service adjustment period.

We seek commuters’ continued understanding and patience as these temporary service adjustments are essential, particularly the service adjustments above that we are conducting immediately after the tunnel works to enable thorough testing before CCL6 opens. When completed, the CCL6 extension will enhance connectivity and bring about shorter travel times and greater convenience to commuters.