The Guardian's website maintained its position as the most popular website of the national titles audited monthly by the bureau with 23,111,862 unique users – a jump of 12.1 per cent from 20,622,063 in July.
Speaking in a press statement, Ed Roussel, digital editor for Telegraph Media Group, said the site's coverage of the Beijing Olympics and the recent conflict in Georgia had proved popular.
A similar size jump was made by Times Online, which attracted 19,690,759 unique users in August – a growth of 3,299,245 (20.1 per cent), which took the site past the 19 million barrier for the first time.
The figures suggest huge year-on-year gains in unique users for the titles: 46 per cent for Guardian.co.uk, 125.8 per cent for the Telegraph site, and 92.3 per cent for Times Online.
In comparison the Times' stablemate the Sun saw only a marginal increase in unique user figures for the month rising from 15,972,490 in July to 15,985,292.
Independent.co.uk recorded a similarly small month-on-month rise in unique users increasing by just 40,306 to 6,629,235, though this brought its year-on-year growth in unique users to 89.6 per cent.
Mail Online was the only national title website audited to report a month-on-month fall in uniques, as it dropped to by 1,237,508 (6.6 per cent) to 17,468,044 for the month.
According to the figures, Mirror Group Digital, which posts combined results for its national and regional portfolio of websites, increased its unique users by 397,778 in August to 5,575,008.