In simple terms
A friendly intro before the formal notes — no formulas yet.
A Country's Statement of Account with the World
The balance of payments records every economic transaction between one country's residents and the rest of the world over a period. It is split so that one part measures what the country earns and spends on trade and income (the current account), and another part measures how that gap is financed by buying and selling assets (the financial account).
Think of a household. The current account is like the monthly budget: wages coming in versus spending on goods, services and interest. If the household spends more than it earns, it runs a deficit — and it must cover that gap somehow: by drawing down savings, selling an asset, or borrowing. Those financing moves are the financial account. For a country, the two sides mirror each other: a current-account deficit is broadly financed by a financial-account surplus (selling assets to, or borrowing from, foreigners).
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Sort each international transaction into the current, capital or financial account.
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Within the current account, net off goods, services, primary income and secondary income.
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A current-account deficit means outflows on those items exceed inflows; a surplus is the reverse.
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The current and financial accounts broadly offset — a deficit on one is matched by a surplus on the other, which links directly to the exchange rate.
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Key formulas
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Full topic notes
Formal explanation with the rigour you need for the exam.
The structure of the balance of payments
The balance of payments records all economic transactions between a country's residents and the rest of the world over a period. Every transaction is either a credit — an inflow of foreign currency, shown with a plus sign, such as an export — or a debit — an outflow, shown with a minus sign, such as an import. The record is split into three accounts, and taken as a whole the balance of payments sums to zero, because each transaction is entered twice with opposite signs.
Current account — trade in goods, trade in services, primary income and secondary income. This is the account examined most heavily in 4.5.
Capital account — a small account for capital transfers (e.g. debt forgiveness) and non-produced, non-financial assets (e.g. patents, trademarks).
Financial account — the ownership of assets: foreign direct investment, portfolio investment, other investment and reserve assets.
The current account and its four components
The current account is the sum of four sub-balances. Learn the four precisely, because Paper 3 questions frequently give you the components and ask you to build the current-account balance from them — or give you the current-account balance and one or two components and ask you to work backwards.
Current account = (Balance of trade in goods) + (Balance of trade in services) + (Primary income) + (Secondary income)
Balance of trade in goods (visible trade): exports of goods minus imports of goods. A deficit here means imports of goods exceed exports.
Balance of trade in services (invisible trade): exports of services (tourism, finance, shipping) minus imports of services.
Primary income (net income): net earnings from factors of production abroad — wages, profit, interest and dividends received minus those paid to non-residents.
Secondary income (net current transfers): one-way flows with nothing given in return — foreign aid, grants and workers' remittances, received minus paid.
The capital and financial accounts
The capital account is small: it records capital transfers such as debt forgiveness and the transfer of non-produced, non-financial assets like patents and copyrights. The financial account is where the action is. It records the net change in the ownership of assets between the country and the rest of the world, and it is the account that finances the current account.
Foreign direct investment (FDI): a lasting interest in an enterprise — building a factory, or a controlling stake in a foreign firm.
Portfolio investment: buying and selling financial assets such as shares and bonds without a controlling interest.
Other investment: loans, bank deposits and trade credit.
Reserve assets: the central bank's holdings of foreign currency and gold, which change as it intervenes in currency markets or finances imbalances.
The single most common structural error on Paper 3 is putting investment flows in the wrong account. Trade and income sit in the CURRENT account; the buying and selling of assets — FDI, shares, bonds, loans — sits in the FINANCIAL account. If a data table lists 'net FDI' or 'portfolio investment' among your current-account figures, it does not belong there. Read the labels before you add anything up.
What a current-account deficit or surplus means
A current-account surplus means the value of credits (exports of goods and services, income and transfers received) exceeds the value of debits (imports, income and transfers paid abroad): the country is a net earner on current transactions. A current-account deficit is the reverse — the country spends more on current transactions with the rest of the world than it earns, so it is a net borrower or seller of assets to cover the gap. Crucially, 'deficit' here refers to the current account as a whole, not just to goods.
Why the current and financial accounts broadly offset
If a country buys more from abroad than it sells, foreigners end up holding its currency. That currency does not vanish — it returns as foreign acquisition of the country's assets: foreigners buy its bonds, lend to it, or invest directly. That inflow is recorded as a financial-account surplus. So a current-account deficit is broadly financed by a financial-account surplus of roughly equal size, and a current-account surplus by a financial-account deficit (the country acquires assets abroad). The word 'broadly' matters: the small capital account and a net errors and omissions item absorb measurement gaps, so the offset is close but not exact in published data.
Ignoring the small capital account and statistical errors: Current account balance $\approx $ − Financial account balance
Causes and consequences of a persistent current-account deficit
A one-off deficit is rarely a worry; a large, persistent deficit deserves analysis. On Paper 3 you may be asked to calculate a deficit and then to comment on it, so keep the causes and consequences ready to deploy on the numbers in front of you.
Causes — loss of competitiveness: if domestic prices or unit labour costs rise faster than trading partners', exports become dearer and imports cheaper, widening the deficit.
Causes — a strong exchange rate: an overvalued currency makes exports expensive and imports cheap.
Causes — high domestic demand and low saving: strong consumption and investment pull in imports and mean the country saves less than it invests, funded from abroad.
Consequences — rising external liabilities: financing the deficit means selling assets or borrowing, so future primary-income outflows (interest, profit, dividends) rise, which can worsen the current account further.
Consequences — vulnerability: reliance on short-term capital ('hot money') is risky, as sudden outflows can force a sharp depreciation or a fall in reserves.
Consequences — it can be sustainable: if foreign capital funds productive investment that raises future export capacity, a deficit need not be damaging.
The current account and the exchange rate
The two are tightly linked through the foreign-exchange market. Current-account credits — exports of goods and services — create demand for the domestic currency, because foreign buyers must acquire it to pay. Current-account debits — imports — create supply of the domestic currency, as residents sell it to buy foreign currency. Under a floating exchange rate, a persistent current-account deficit tends to put downward pressure on the currency, because the supply of the currency runs ahead of demand. The resulting depreciation makes exports cheaper and imports dearer, which over time can help narrow the deficit — a self-correcting mechanism, though one that works with lags.
Common mistakes examiners penalise
Confusing the current and financial accounts — putting FDI, shares, bonds or loans in the current account. Investment flows are financial-account items; the current account is trade and income only.
Treating 'balance of trade' as the whole current account — the goods balance is one of four components. Forgetting services, primary income or secondary income gives the wrong current-account figure.
Saying a current-account deficit simply means 'imports > exports' — that describes the goods (or trade) balance. A current-account deficit means total current-account debits exceed total current-account credits across all four components.
Dropping signs and units — on Paper 3, an answer without a minus sign, or without '$bn', or without stating 'surplus'/'deficit', forfeits the accuracy mark even when the arithmetic is right.
Omitting the working line — no shown method means no method mark and no follow-through, so a single arithmetic slip can cost every mark instead of one.
Claiming the accounts offset exactly — they broadly offset; the small capital account and net errors and omissions absorb the difference in real data.
Where this leads
The balance of payments is the bridge between a country's trade (Topic 4.1–4.4) and its exchange rate and macroeconomic policy. Once you can build and interpret the accounts, the next questions follow naturally: how exchange-rate changes feed back into the current account, and whether governments should act on a persistent deficit. Every one of those debates rests on the framework — and the calculation skills — you have built here.
Worked examples
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A country records: exports of goods $300bn, imports of goods $360bn, net trade in services +$40bn, net primary income −$10bn, net secondary income +$5bn. Calculate the balance of trade in goods and the current-account balance. [4]
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Step 1 — Balance of trade in goods. Balance of trade in goods = exports of goods − imports of goods = 360bn = −$60bn (a deficit on goods, as imports exceed exports).
The country in the earlier example has a current-account deficit of $25bn. Its capital account is +$2bn and net errors and omissions are −$1bn. Calculate the balance on the financial account, and state what it tells you about the flow of capital. [3]
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Step 1 — Use the balance-of-payments identity. The whole balance of payments sums to zero: Current account + Capital account + Financial account + Net errors and omissions = 0.
How it all connects
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Glossary
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Revision flashcards
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Balance of payments
A record of all economic transactions between the residents of a country and the rest of the world over a given period. It is divided into the current account, the capital account and the financial account.
Key takeaways
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Current account — trade in goods, trade in services, primary income and secondary income. This is the account examined most heavily in 4.5.
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Capital account — a small account for capital transfers (e.g. debt forgiveness) and non-produced, non-financial assets (e.g. patents, trademarks).
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Financial account — the ownership of assets: foreign direct investment, portfolio investment, other investment and reserve assets.
Practice — then mark it
The whole point: a real Cambridge question, marked mark-by-mark.
Get a Paper 3 calculation marked: compute the balance of trade in goods and the current-account balance from raw data
Get a Paper 3 calculation marked: compute the balance of trade in goods and the current-account balance from raw data
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