When you open a position, you are long (buying) one currency and short (selling) the other currency. You will receive holding charges/credits on the currency which you are long, calculated using the bid financing rate, and pay holding charges/credits on the currency which you are short, calculated using the ask financing rate.
Please note that in some cases, the bid financing rates will be negative. In these cases, you will pay holding charges/credits on the currency which you are long.
Financing rates are determined from various sources, including central bank interest rates and spot-next rollover rates received from our LPs.
For example, let’s say you have entered into a trade to sell GBP/USD. This means that you hold a short position in GBP and a corresponding long position on USD. If the OANDA financing rates are as follows: