Subsidy vs Tariff
Subsidy and Tariff are related concepts in AP Economics that students often mix up. A subsidy is a government payment to producers to lower production costs and encourage output. A tariff is a tax on imported goods that raises their price and protects domestic producers from foreign competition. Here is how they compare side by side.
Governments use subsidies to support industries they consider important, such as agriculture or renewable energy. By lowering costs, subsidies allow producers to increase output and offer goods at lower prices. However, subsidies can lead to market inefficiencies and overproduction.
It raises government revenue and helps domestic producers, but raises prices and reduces quantity for consumers, creating deadweight loss. It reduces imports and the overall gains from trade. Tariffs are a common form of trade protection.
Subsidy vs Tariff: Two Ways to Protect Domestic Producers, With Very Different Bills
| Subsidy | Tariff | |
|---|---|---|
| Effect on the government budget | Costs money, the payment times subsidized output | Raises money, the tariff times the units still imported |
| Price consumers pay | Unchanged at the world price, so buyers lose nothing | Rises by the full tariff, on domestic units as well as imported ones |
| Who funds the help | Taxpayers in general | Buyers of that one good |
| Deadweight loss | One triangle, from domestic units produced above world cost | Two triangles, one from inefficient production and one from consumption given up |
| How it cuts imports | Only by raising domestic supply, consumption is untouched | From both ends, more domestic supply and less consumption |
| Other place it appears in the course | Micro externality correction, where a per unit subsidy raises welfare | Trade policy only, with no imports there is nothing to tax |
Protecting the same domestic output costs society three times as much through a tariff
Set the world price at 8 dollars. At that price domestic firms supply 20 units and domestic buyers want 90, so imports are 70. Now add a tariff of 4 dollars. The domestic price rises to 12, domestic supply rises to 30, quantity demanded falls to 70, and imports shrink to 40. Consumers lose the area between the two prices under their demand curve, 320. Producers gain 100. The government collects 4 dollars on 40 imported units, or 160. What nobody receives, 60, is deadweight loss, splitting into a production triangle of 20 and a consumption triangle of 40. Now buy the same protection with a production subsidy of 4 dollars per unit. Domestic firms still receive 12 and still supply 30, but consumers keep paying the world price of 8, so they still buy 90 and lose nothing. Imports fall to 60. The treasury pays 4 dollars on 30 units, or 120. Deadweight loss is the production triangle alone, 20. Identical domestic output, one third of the welfare cost, and a bill of 120 rather than revenue of 160.
The revenue rectangle is a transfer, and shading it as loss is the classic tariff error
On a tariff diagram there are four areas between the world price line and the tariff inclusive price, and a grader is checking that you assign each one correctly. The leftmost is producer surplus gained by domestic firms, a transfer from buyers to sellers. The rectangle in the middle is government revenue, a transfer from buyers to the treasury. The two triangles flanking that rectangle are the only genuine losses. Students routinely shade the revenue rectangle as deadweight loss and report a welfare cost several times too large, 220 instead of 60 in the example above. The subsidy diagram carries its own version of the trap. The government payment is a real cost to taxpayers, but most of it lands as producer surplus, so the 120 paid out is not the welfare loss either. In both cases, identify the loss as the areas nobody receives, then check that answer against the triangle formula.
A subsidy does two different jobs in this course, a tariff only one
Tariffs exist because of imports. Remove foreign supply and a tariff has nothing to tax. Subsidies show up in two separate places. In trade, a production subsidy is the cheaper way to keep a domestic industry running. In microeconomics, a per unit subsidy is the standard correction for a positive externality: set the subsidy equal to the marginal external benefit so that private decisions face the social marginal benefit and the market lands at the efficient quantity. In that second use the subsidy raises welfare instead of destroying it, because it fixes an existing distortion rather than creating one. If a question shows a market with an external benefit and asks for policy, the answer is a subsidy and the deadweight loss falls to zero. If a question shows a world price line, you are in trade policy, where any intervention adds loss rather than removing it.
Frequently asked questions
Why does a tariff cause more deadweight loss than a subsidy that supports the same output?
A tariff distorts two decisions while a production subsidy distorts one. The tariff pulls inefficient domestic firms into producing, and it also pushes consumers out of buying units they valued above the world price. The subsidy causes the first distortion only, since consumers keep facing the world price and their quantity never changes. In the worked example above the tariff destroys 60 of surplus and the subsidy destroys 20, for identical domestic production of 30 units.
If a subsidy is cheaper for society, why do governments still use tariffs?
Tariffs pay for themselves and subsidies do not. A tariff generates revenue and buries its cost inside the shelf price, where no voter sees a line item. A subsidy needs an appropriation that appears in the budget every year and can be cut. Tariffs are also easier to aim at a single trading partner, and a legislature can pass one without finding money for it. The economics favors the subsidy, the politics favors the tariff.
Does a tariff raise the price of domestically produced units too?
Domestic producers raise their price to match the tariff inclusive import price, so buyers pay more on every unit, not only on imported ones. That is why the consumer loss on a tariff diagram is measured across the whole quantity demanded while government revenue is collected only on the units still imported. In the worked example the price rises from 8 to 12 on all 70 units bought, yet revenue arrives on just the 40 units imported, with the other 30 sold by domestic firms at the higher price.
Live Supply and Demand graph. Drag the curves, or open the full version.
Live International Trade graph. Drag the curves, or open the full version.
Related comparisons
Get AP Econ exam tips in your inbox
Occasional emails with study tips, new interactive graphs, and exam-season reminders. Free, no spam.
No spam. Unsubscribe anytime. Read our privacy policy.
Keep track of what you have studied
A free EconLearn account adds progress tracking, your quiz history, and achievements. Studying here is free either way, and there is nothing to pay for as a student.
Create a free accountAlready have one? Sign in
Last updated