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Query regarding international transaction between governments 
For the US government, they've just credited Person B with a Million USD and haven't gained anything (afterall, those digits are intangible and don't really have a value, IMO). Two flaws in this reasoning: The US government didn't do anything. The receiving bank credited the recipient. If the digits are intangible, such that they haven't gained anything, they haven't lost anything either. In practice, the role of governments in the transfer is purely supervisory. The sending bank debits the sender's account and the receiving bank credits the recipient's account. Every intermediary makes some money on this transaction because the cost to the sender exceeds the credit to the recipient. The sending bank typically receives a credit to their account at a correspondent bank. The receiving bank typically receives a debit from their account at a correspondent bank. If a bank sends lots of money, eventually its account at its correspondent will run dry. If a bank receives lots of money, eventually its account at its correspondent will have too much money. This is resolved with domestic payments, sometimes handled by governmental or quasi-governmental agencies. In the US, banks have an account with the federal reserve and adjust balances there. The international component is handled by the correspondent bank(s). They also internally will credit and debit. If they get an imbalance between two currencies they can't easily correct, they will have to sell one currency to buy the other. Fortunately, worldwide currency exchange is extremely efficient.