BUDGET airline Ryanair saw shares hit an all-time high after a drive to improve its image helped attract a million extra passengers last month.

The Dublin-based carrier said passenger numbers in December jumped 20 per cent on a year before to 6.02 million.

Its load factor, a measure of how full the planes are, increased seven per cent to 88 per cent over the last 12 months.

The surge follows a drive by Ryanair to improve customer service by softening its stance on baggage charges and booking conditions after suffering two profit warnings at the end of 2013.

Its shares lifted more than three per cent on the Irish stock exchange and have jumped 59 per cent over the past year.

Over the 12 months to December, the airline, led by chief executive Michael O'Leary, said passenger numbers lifted six per cent to 86.4 million.