The company said that 35.6 million people used its Mini browser in September to view, download and consume content while on the road.
The report claimed that, on a monthly basis, users in the US and the UK are saving the most money, based on usage and the average cost per megabyte of browsing.
Opera explained that, although the amount of data its users are consuming has risen by 224 per cent since the same time last year, the load is much less than it could be because Opera Mini compresses this information by up to 90 per cent, hence the £4.9m savings.
Opera found that UK users are looking at roughly 225 pages per month, and that the most visited sites are Facebook, Google and the BBC. The three most popular handsets for Opera Mini users in the UK are the LG KC910 (Renoir), Nokia 6300 and LG KE970 (Shine).
"We are on a mission to bring the web to everyone, on their terms," said Jon von Tetzchner, chief executive at Opera.
"More than half the world's population has a mobile phone. By making the mobile web more affordable and available on almost any mobile phone, we help democratise it. This means we can expand the reach of the web in a way that defies imagination."
Opera said that its Mini user base has grown by 150 per cent over the past 12 months, and by 11 per cent during the previous month. Page views have risen by 7.2 per cent since August, and by 230 per cent since the same time last year. The firm claimed that its users view an average of 500 million pages a day.
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