New Delhi, July 8 -- India's urban story is often told through the lens of its six megacities-Delhi, Mumbai, Bengaluru, Chennai, Kolkata and Hyderabad. But this narrative misses the real transformation underway: the rise of 100 diverse cities, each shaping the country's economic, social and consumption future in unique ways. As India prepares to add 40 million new urban residents by 2030, these 100 cities will form the crucible of the nation's next leap forward.

Beyond the megacity-four tiers, one urban engine: The top 100 cities account for just 19% of India's population but generate 35% of national income and account for 31% of consumption. If these cities were a country, their $844 billion in annual spending would make them the world'...