However, Karnataka, Haryana, and Uttar Pradesh have emerged as close contenders to the top-three states. GSTN is the company that processes the tax returns for goods and services tax (GST), the levy on consumption.

While India's IT hub Karnataka is ranked the fourth largest among the states by the value of goods transported within the state for which e-way bills were generated, the most populous state, Uttar Pradesh and Haryana, with a strong industrial and agriculture base, follow closely at fifth and sixth places respectively, e-way bill data for April showed.

E-way bill data captures shipments valued at ₹50,000 or more for distances beyond 50 kilometres and indicates economic activity. But the assessable value of goods shipped cannot be taken as the accurate indicator of either consumption or trade.

Tamil Nadu, with a strong automobile industry in addition to IT and agriculture sectors, is the third largest in terms of the value of goods shipped to the rest of the country after the top-ranking states in this regard—Maharashtra, the most industrialized state in the country, and Gujarat, which has a strong base in energy and manufacturing—e-way bill data showed. Tamil Nadu is followed by Haryana, Uttar Pradesh, and Karnataka in April for the next consecutive rankings in terms of the value of goods shipped to the rest of the country for which e-way bills were raised.

The three states with the highest value of goods locally shipped and transported to the rest of the country are also the largest states that see inbound shipments from the rest of the country. Importing states receive revenue from the integrated goods and services tax (IGST) levied on the inter-state sale of goods, as GST is a destination-based tax on consumption.

After Maharashtra, Gujarat, and Tamil Nadu, which remain top states in terms of the value of inbound shipments, Uttar Pradesh, Haryana, Karnataka, and Delhi rank as fourth, fifth, sixth, and seventh largest importing states.

Data for March, too, confirms the rankings, except for outbound shipments, where Karnataka was the fifth largest, above Uttar Pradesh.

The aggregate number of e-way bills generated is taken as a high-frequency indicator for economic activity by analysts, and the more granular data shows the trends in local shipments of goods and inter-state transportation, a valuable tool for businesses and policymakers. However, the aggregate assessable value of shipments within a state or inter-state shipments would be quite different from the actual consumption or inter-state trade by the states.

According to Archit Gupta, the founder and CEO of Clear, a business-to-business fintech software-as-a-service (SaaS) company, a taxable person ​registered under GST ​and is involved in the transportation of goods with value exceeding the specified threshold must ​do so after generating an e-way bill. For such a person, an e-way bill is mandatory for transportation of goods for all types of transactions such as outward and inward supply, whether within the state or across states. "E-way bill is ​also ​required for the movement of goods from one unit of the firm to another unit​. Therefore aggregated assessable value of e-way bills generated does not truly reflect the total consumption by the state as such," said Gupta.