The effect of taxes on supply and demand

One form of government intervention is the introduction of taxes. Taxes are typically introduced to increase government revenue, but they also have the effect of raising the cost of goods and services to the consumer. Because of the increased cost, we generally see a reduction in the quantity of goods and services produced and consumed after the introduction of taxes. A common form of tax is a sales tax, which is added on to the price of a product and paid by the consumer. Another common type of tax is a VAT (value added tax) which is paid by the producer along their production chain.



The sales tax on the consumer shifts the demand curve to the left, symbolizing a reduction in demand for the product because of the higher price. While demand for the product has not changed (all of the determinants of demand are the same), consumers are required to pay a higher price, which is why we see the new equilibrium point occurring at a higher price and lower quantity. The magnitude of the shift in the demand curve will be equal to the amount of the tax. This makes sense, because the change in demand is going to be equal to the change in price that is caused by the tax.

Taxes on supply and demand

The VAT on the suppliers will shift the supply curve to the left, symbolizing a reduction in supply (similar to firms facing higher input costs). While supply for the product has not changed (all of the determinants of supply are the same), producers incur higher cost, which is why we will see a new equilibrium point further up the demand curve at a higher price and lower quantity. Once again, the magnitude of the shift in the supply curve will be equal to the amount of the tax introduced by the government. Essentially, the firms are passing on the tax to the consumers in the same way they would pass on higher input costs.

Another type of tax is a labor tax. This increases the price of labor to firms (because they have to pay the wage AND the tax) which will decrease employment and wages.