Tamil Nadu has a well established transportation system that connects all parts of the state. This is partly responsible for the investment in the state. Though the present transportation system is substantial, it needs to be developed further to keep pace with the rapid increase in use. Tamil Nadu is served by an extensive road network in terms of its spread and quality, providing links between urban centers, agricultural market-places and rural habitations in the countryside. There are 24 national highways in the state, covering a total distance of 2,002 km. The state is also a terminus for the Golden Quadrilateral project that is scheduled to complete in 2008. The state has a total road length of 167,000 km, of which 60,628 km are maintained by Highways Department. This is nearly 2.5 times higher than the density of all-India road network.

Tamil Nadu has a well developed rail network as part of Chennai. Headquartered at Chennai, the present Southern Railway network extends over a large area of India`s Southern Peninsula, covering the states of Tamil Nadu, Kerala, Pondicherry, a major portion of Karnataka and a small portion of Andhra Pradesh. Tamil Nadu has a total railway track length of 6,693 km and there are 690 railway stations in the state. The system connects it with most major cities in India. Main rail junctions in the state include Chennai, Coimbatore, Madurai and Tiruchirapalli. Chennai has a well-established Transport network and is in the process of developing a metro.

Tamil Nadu has a major international airport, Chennai International Airport, that is connected with 19 countries with more than 169 direct flights every week. This is currently the third largest airport in India after Mumbai and Delhi and has a passenger growth of 18%. It also has domestic airports at Coimbatore, Trichy, Tuticorin and Madurai make several parts of the state easily accessible. Increased industrial activity has given rise to an increase in passenger traffic as well as freight movement which has been growing at over 18 per cent per year. Tamil Nadu has three major ports at Chennai, Ennore and Tuticorin, as well as one intermediate port, and seven minor ports, Rameswaram, Kanyakumari, Cuddalore, Colachel, Karaikal, Pamban and Valinokkan of which are currently capable of handling over 73 million metric tonnes of cargo annually (24 per cent share of India).

All the minor ports are managed by the Tamil Nadu Maritime Board. Chennai Port is an artificial harbour situated on the Coromandel Coast in South-East India and it is the second principal port in the country for handling containers. Ennore Port was recently converted from an intermediate port to a major port and handles all the coal and ore traffic in Tamil Nadu. The volume of cargo in the ports grew by 13 per cent over 2005. The Sethusamudram Shipping Canal Project will transform the Tuticorin port into a transhipment hub similar to those in Singapore and Colombo. The ports are in need of improvement and some of them have container terminals privatized.