The North–South Corridor (Abbreviation: NSC), originally conceptualised as the North-South Expressway, will be the 11th of Singapore‘s network of expressways when completed. The North South Corridor will serve increasing traffic along the north-south corridor that is currently served by the Central Expressway (CTE). This new expressway was announced on 30 January 2008 as part of a major review of Singapore’s transport network by the Land Transport Authority (LTA). The 21 kilometres (13 mi) expressway would cost about S$7–8 billion when fully completed in 2026 as North-South Corridor and will connect the East Coast Parkway (ECP) with the northern parts of Singapore.
The NSC will have a total of 16 entrances and 17 exits to connect towns along the north-south corridor—Woodlands, Sembawang, Yishun, Ang Mo Kio, Bishan and Toa Payoh—with the city centre. The NSC will also provide links to existing expressways, including the Seletar Expressway (SLE), Pan-Island Expressway (PIE) and East Coast Parkway (ECP).
According to the Land Transport Authority, the continuous bus lanes along the NSC would be able reduce bus travelling times from Woodlands, Sembawang, Yishun and Ang Mo Kio to the city by up to 30 minutes through morning and evening peak express bus services, and also make bus connections between residential towns along the NSC faster by allowing intra-town buses to leverage the ramps and bus lanes on the surface, A cycling path along the entire stretch of the highway will link up Park Connector Networks and the dedicated cycling path networks within HDB towns along the entire corridor to the city centre.
The North-South Corridor was initially targeted to be ready by 2023. However, due to significant delays in construction, the deadline has been pushed back to 2026.
On 19 January 2011, the government gave the green light to build the expressway between Admiralty Road West and Toa Payoh Rise. On 15 November 2011, LTA unveiled the full alignment of the North-South Corridor.
While first conceptualised as a vehicular expressway to be finished in 2020, the corridor will now be built as the island’s first “integrated transport corridor” featuring continuous bus lanes and cycling trunk routes, throughout the entire route of the expressway. Construction was initially planned to begin in 2017, with an expected completion date of 2023. However, the first contract was only awarded in November 2017, with works commencing in early 2018. 
The North-South Corridor is now targeted to be completed by 2026.
In the final plan, the NSC will commence at Admiralty Road West in northern Singapore and proceed southwards along Woodlands Avenue 8, Gambas Avenue, Sembawang Road. It will join Lentor Ave and intersect the Seletar Expressway. Major bus stops will be equipped with lift lobbies at Lentor Avenue, Ang Mo Kio Avenue 6 and Marymount Road. It will also pass through the two military training areas – Lentor and Seletar East, both of which will be cleared by 2017. It will pass Toa Payoh Rise, join Thomson Road and Bukit Timah Road running parallel to the Central Expressway. The NSC will carry on along Ophir Road, joining the East Coast Parkway at its southern terminus. In addition, there will be new bus lanes and cycling lanes.
Some land has to be acquired by the government for the project. The Land Transport Authority tried to utilize state land as far as possible, reducing the number of private properties that have to be acquired. Despite much of the expressway running underground at its southern end, some land had to be taken because of existing Mass Rapid Transit tunnels, and also because the expressway had to be straight to maintain traffic speeds. One of the prominent landmarks that has to make way for the project is the Rochor Centre. Novena Square underpasses will also be demolished, and the former Ellison Building may be considered for demolition.