The balance of trade, also known as the trade balance or net exports, is the difference between the monetary value of a countrys exports and imports over a certain time period. It is a net measurement, usually expressed in the exporting countrys currency, and it measures the flow of exports and imports over a given period of time. A positive balance of trade, also known as a trade surplus, occurs when a country exports more goods than it imports, while a negative balance of trade, or a trade deficit, exists when the imports exceed exports. The balance of trade is part of a larger economic unit, the balance of payments, which includes other transactions such as income from the net international investment position as well as international aid. The balance of trade forms part of the current account, and if the current account is in surplus, the countrys net international asset position increases correspondingly. Conversely, a deficit decreases the net international asset position.

Calculating the balance of trade involves subtracting the value of a countrys imports from the value of its exports. A favorable balance of trade, or a trade surplus, occurs when a country exports more goods than it imports, and it is generally seen as a sign of economic strength. However, a positive or negative trade balance does not necessarily indicate a healthy or weak economy, and whether a positive or negative balance of trade is beneficial for an economy depends on the countries involved, the trade policy decisions, the duration of the positive or negative balance of trade, and the size of the trade imbalance, among other things. Economists generally agree that neither trade surpluses nor trade deficits are inherently "bad" or "good" for the economy.