Strong Total, Weaker Core: Why a Record Import Share Changes How We Should Read September's ₹2.03 Lakh Crore GST

When the Border Collects More of the Tax A

14.7% jump to ₹2.03 lakh crore sounds like a busy economy. Look at where the money came from and the picture changes. Of every ₹100 of gross GST collected in September, a record ₹32.2 came from goods arriving at India's ports and airports.

Only ₹67.8, the lowest share ever, came from transactions inside the country. Domestic GST did not shrink. It grew 10.1%. But import GST grew 25.9%, more than twice as fast, so the domestic share fell.

How a

weaker rupee becomes more tax Here is the mechanism and why it matters. GST on imports, collected as IGST at customs, is charged on the rupee value of the goods. Consider an electronics distributor importing a container of components priced in dollars.

If the rupee weakens, the same container costs more in rupees and the tax on it rises with that price. The tax has gone up even though nothing more was imported. The same happens when global prices of imported goods rise.

Manoj Mishra of Grant Thornton Bharat said this gap reflects currency, commodity prices and import trends. An important detail: the biggest commodity India imports, crude oil, sits outside GST, along with petrol, diesel, aviation fuel and natural gas.

So oil price spikes do not feed this number directly. The effect comes through other imports such as electronics, machinery, metals and gold. A second effect is less visible. Most IGST paid at customs is not final revenue.

A business that imports inputs can claim that tax as input tax credit and use it to pay the GST it owes on its own sales. So when import tax paid at the border rises, the cash collected later from domestic returns can fall, partly because tax was prepaid at the border.

A rising import share can therefore make domestic collections look weaker than domestic activity really is.

Who should worry and who shouldn't The domestic figure deserves more credit than the share suggests.

The rate cuts that took effect on September 22, 2025 mean this year's domestic transactions are taxed at lower rates than last year's. Monthly collections mostly reflect the previous month's sales. So growing 10.1% at lower rates suggests real growth in volume. M.S. Mani of Deloitte India also credited simpler compliance and more GST audits. The worry is for planners, not for the economy's immediate health:

• Budget forecasts. Revenue linked to exchange rates and commodity prices can reverse quickly if the rupee strengthens or global prices fall. A budget built on September's growth rate assumes those external conditions will last.
• States. States depend heavily on GST. Revenue tied to import values is more volatile than revenue tied to local consumption.
• Reading the economy. Commentators often treat the GST total as a stand-in for consumption. With a third of it now coming from imports, the total partly measures the rupee's value and global prices.
• Domestic producers. Fast import growth alongside slower domestic growth can mean imports are meeting more of India's demand, which squeezes local manufacturers, especially small firms, competing with them. For the exam, the insight is that a GST total is a sum of two very different streams. The domestic stream tells you about Indian economic activity. The import stream increasingly tells you about the rupee and world prices. Reading only the total hides that difference.