The financing cost for your CFD trade is referred to as ‘rollover.' This is the interest paid depending on the size of the position and for holding a position past 23:59:59 GMT. For index CFDs, any dividend adjustments issued are included in the rollover amount as well.
The formula for financing costs (for a product such as indices) is as follows:
Closing Price of the Index * the interest rate / 100 / Number of Days +/- Dividends * Trade Size
Pay attention to open positions on Fridays. If you hold a position over the weekend on rolling commodities or indices, the rollover is charged 3 times as you’ll be unable to close a position until the markets open on Monday AM. When trading forex, most 3 rolls will be charged on Wednesdays, however some exceptions may apply.
To avoid rollover charges, make sure to close any open positions before 20:59:59 GMT.