To understand this, let us first understand what is Input Tax Credit. It is the credit an individual receives for the tax paid on the inputs used in manufacturing the product. So, if there is a 10% tax that the individual must submit to the government, he can subtract the amount he has paid in taxes at the time of purchase and submit the balance amount to the government.

Let us understand this with a hypothetical numerical example.

Say a shirt manufacturer pays Rs. 100 to buy raw materials. If the rate of taxes is set at 10%, and there is no profit or loss involved, then he has to pay Rs. 10 as tax. So, the final cost of the shirt now becomes Rs (100+10=) 110.

At the next stage, the wholesaler buys the shirt from the manufacturer at Rs. 110, and adds labels to it. When he is adding labels, he is adding value. Therefore, his cost increases by say Rs. 40. On top of this, he has to pay a 10% tax, and the final cost therefore becomes Rs. (110+40=) 150 + 10% tax = Rs. 165.

Now, the retailer pays Rs. 165 to buy the shirt from the wholesaler because the tax liability had passed on to him. He has to package the shirt, and when he does that, he is adding value again. This time, let’s say his value add is Rs. 30. Now when he sells the shirt, he adds this value (plus the VAT he has to pay the government) to the final cost. So, the cost of the shirt becomes Rs. 214.5 Let us see a breakup for this:

Cost = Rs. 165 + Value add = Rs. 30 + 10% tax = Rs. 195 + Rs. 19.5 = Rs. 214.5

So, the customer pays Rs. 214.5 for a shirt the cost price of which was basically only Rs. 170 (Rs 110 + Rs. 40 + Rs. 30). Along the way the tax liability was passed on at every stage of transaction and the final liability comes to rest with the customer. This is called the Cascading Effect of Taxes where a tax is paid on tax and the value of the item keeps increasing every time this happens.

In the case of Goods and Services Tax, there is a way to claim credit for tax paid in acquiring input. What happens in this case is, the individual who has paid a tax already can claim credit for this tax when he submits his taxes.

In our example, when the wholesaler buys from the manufacturer, he pays a 10% tax on his cost price because the liability has been passed on to him. Then he adds value of Rs. 40 on his cost price of Rs. 100 and this brings up his cost to Rs. 140. Now he has to pay 10% of this price to the government as tax. But he has already paid one tax to the manufacturer. So, this time what he does is, instead of paying Rs (10% of 140=) 14 to the government as tax, he subtracts the amount he has paid already. So, he deducts the Rs. 10 he paid on his purchase from his new liability of Rs. 14, and pays only Rs. 4 to the government. So, the Rs. 10 becomes his input credit.

When he pays Rs. 4 to the government, he can pass on its liability to the retailer. So, the retailer pays Rs. (140+14=) 154 to him to buy the shirt. At the next stage, the retailer adds value of Rs. 30 to his cost price and has to pay a 10% tax on it to the government. When he adds value, his price becomes Rs. 170. Now, if he had to pay 10% tax on it, he would pass on the liability to the customer. But he already has input credit because he has paid Rs.14 to the wholesaler as the latter’s tax. So, now he reduces Rs. 14 from his tax liability of Rs. (10% of 170=) 17 and has to pay only Rs. 3 to the government. And therefore, he can now sell the shirt for Rs. (140+30+17) 187 to the customer.