North–South Expressway southern route

The expressway begins at the Sungai Besi toll plaza. The Kuala Lumpur–Seremban Expressway links Sungai Besi toll plaza to Jalan Istana and the Besraya Expressway near the Sungai Besi RMAF base.

From this point the expressway enters Negeri Sembilan, running southwesterly towards Nilai. The interchange to ELITE E6 lies in the northern part of Nilai, near the Selangor–Negeri Sembilan border, enabling motorists from the south to Shah Alam and Klang while bypassing Kuala Lumpur.

The expressway becomes a four-lane dual-carriageway expressway.

On the last segment, the expressway finally terminates at its interchange with the Johor Bahru Eastern Dispersal Link Expressway.

Orange emergency telephones/callboxes are located every two kilometres along the entire expressway, as with every other expressway in the PLUS expressway network.[1] Alternatively, commuters may dial the toll-free number 1 800 88 0000 on their mobile phones. Both will connect to the PLUS traffic monitoring centre in Subang where commuters may request for traffic information or roadside assistance.[5] The highway patrol and roadside assistance teams are known as PLUSRonda. They provide free first responder services including small fixes for broken down vehicles, towing and also act as traffic police when there is an incident.[6] They are also given auxiliary police powers.[1]

PLUS also provides traffic information to commuters through variable-message signs located on some sections of the expressway, and on Twitter @plustrafik in Malay.[1][7] Major radio stations in Peninsular Malaysia also broadcast traffic updates for the expressway.

Pagoh Rest and Servica Area

The North–South Expressway southern route has 8 full rest areas (which includes one overhead bridge restaurant), 20 laybys and one vista point (scenic area) total along both directions of the expressway. Every rest area and layby includes, as a bare minimum, car parks and public toilets. Most laybys also include public telephones and a small rest hut. Depending on location, laybys can also include petrol stations, a surau, and rarely, food courts, independently operated restaurants and automated teller machines. Full rest and service areas have all of the above services and are much larger, so they can accommodate more services. Several rest areas also have small inns, and most have complimentary Wi-Fi services.[8][9] Vista points only have car parks and are meant for commuters to enjoy the scenery at that location.[10] Laybys are found every 25 to 50 kilometres, while full rest areas are found every 80 to 100 kilometres. The only vista point on this expressway is in Pedas Linggi.

The Senawang Interchange and the Ayer Keroh Interchange received new four lane sections in 2003. The Ayer Keroh Interchange had two-lane carriageways until 2009, when it was upgraded to three and four lanes, ending at Sungai Besi commencing again at E37 Kuala Lumpur–Seremban Expressway.

In July, 2007, a six lane section from Kuala Lumpur to Seremban Interchange Exit 218 was extended to Senawang Interchange Exit 220.

The next phase of these works, the extension of the Senawang Interchange Exit 220 to the Ayer Keroh Interchange Exit 231 was completed in December, 2007.

On July 2010, the operator, PLUS Expressways Berhad, announced that the government had awarded contracts to build a fourth lane on a stretch from Nilai (North) to Seremban. The construction has already begun at the south bound, with its north bound will be begin soon.

An interchange between Tangkak and Pagoh Interchange was opened to traffic on March 2014, there will be three interchange that will be linking from the interchanges to Muar, Johor.

An interchange between Nilai and Seremban Interchange was opened to traffic on 10 July 2015, there will be four interchange that will be linking from the interchanges to Seremban, Negeri Sembilan.

An interchange between Bangi and Putra Mahkota Interchange was opened to traffic on April 11 2018, there will be five interchange that will be linking from the interchanges to Bangi, Selangor.