The payment for transferring an open position overnight. May be both positive and negative. The night from Wednesday to Thursday triples the payment. The swap payment is based on the interest rate differential between the two currencies in a currency pair on which the trade position is rolled over to the next trading day. The swap is positive if the trader has a long position on the currency with the higher interest rate, and negative when the trader is short on the higher yielding currency (or long on the lower yielding currency).