Britain is shrugging off its prudish image after a study found its citizens to be the most promiscuous of any large western industrial nation, while Australians ranked fifth.
An international index measuring one-night stands, total numbers of partners and attitudes to casual sex also put Britain ahead of second-placed Germany, with the Netherlands third, the Czech Republic fourth and the US sixth.
Researchers behind the study say high scores such as Britain's may be linked to society's increasing willingness to accept sexual promiscuity among women as well as men.
David Schmitt, a professor of psychology at Bradley University in the American state of Illinois, oversaw the research.
He told The Sunday Times: "Historically we have repressed women's short-term mating and there are all sorts of double standards out there where men's short-term mating was sort of acceptable but women's wasn't."
The study surveyed more than 14,000 people in 48 countries through anonymous questionnaires.
Respondents were asked about numbers of partners and one-night stands, and their attitudes were assessed by asking them how many people they expected to sleep with over the next five years and how comfortable they were with the idea of casual sex.
Their answers were used to give a so-called "sociosexuality" score with a numerical value used by scientists to measure how sexually liberal people are in thought and behaviour.
The country with the highest average score was Finland, while Taiwan had the lowest.
Britain's score placed it 11th overall, but it was highest among leading industrial nations.
The first results of the survey were published in 2005, but analysis has continued and Schmitt revealed the latest findings in this week's edition of New Scientist magazine.
Britain's ranking was attributed to factors such as the decline of religious scruples about extramarital sex, the growth of equal pay and equal rights for women and a highly sexualised popular culture.
The promiscuity rankings
1 United Kingdom
2 Germany
3 Netherlands
4 Czech Republic
5 Australia
6 USA
7 France
8 Turkey
9 Mexico
10 Canada
11 Italy
12 Poland
13 Spain
14 Greece
15 Portugal