Chennai has a diversified economic base anchored by the automobile, software services, hardware manufacturing, healthcare and financial services industries.As of 2000, the city total personal income was Rs. 12,488.83 crores, making up 10.9% of the total income of Tamil Nadu.In 2001, the total workforce in Chennai was about 1.5 million, which was 31.79% of its population.

According to the 1991 census, most of the city workforce was involved in trade (25.65%), manufacturing (23.52%), transportation (10.72%), construction (6.3%) and other services (31.8%). Chennai metropolitan area accounts for over 75% of the sales tax revenue in the state. According to the CII, Chennai is estimated to grow to a $100-billion economy, 2.5 times its present size, by the year 2025.