No JulietNovemberPapa, as I said it's irrelevant who books one ways or returns. Ryanair are currently carrying in the region of 50m passengers per annum. This is calculated on a per sector basis so a person booking a return trip is two passengers. Therefore it may be that 12.5m are booking returns and 25m booking singles but since the credit card charge is per sector it doesn't matter how the 50m figure is arrived at.