You can earn up to 100 Bonus Miles each month by driving safely. We calculate your Bonus Miles using information from the black ox in your car. The safety factors we consider include speed, time of day, smooth driving, taking breaks on long journeys and the type of road you drive on. You can also earn more Bonus Miles by using the motorway more often. The motorway is statistically safer than other types of road, so we reward customers who drive more of their miles on the motorway.