Nearly three-quarters of people in the UK believe in a God, yet less than a quarter attend religious services as regularly as once a week or more, according to a survey.
Asked if they believed in a God - as in a supernatural being or "creator" - 72% of people said they did. However, almost a third - 31% - said they did not associate with any particular religion, the survey found.
A team from GfK Custom Research interviewed more than 21,000 people, aged 15 and over, from 21 countries on their religious attitudes for The Wall Street Journal Europe.
In the UK, 69% of people said they did associate with a particular religion - compared to 75% in the US, 85% in Italy and 97% in Romania. The average across all 21 countries was 73%.
Of those in the UK, 40% identified themselves as Protestants, 29% as Catholics and 4% as Muslims. More women than men (74% as against 63% ) said they identified with a particular religion - one of the widest gender gaps in Europe.
Asked how often they attended religious services, 20% of those who did identify with a particular religion answered "almost never", while another 22% said only between once and four times a year.
The proportion who said they attended once a week or more was just 24%, according to the survey. This compared with 43% in the US, 61% in Poland and 72% in Turkey.
In all, across all 21 countries, an average of only 15% of people said they did not believe in a God. In the UK, a fifth of people - 22% - said they felt there had been "somewhat more" anti-semitism in the country in the past five years, while a further 12% felt there was "much more".
Asked if they thought there was any "disapproval" of Muslims living in European society, 18% of people in the UK said "definitely a lot" while another 21% said "rather a lot".
The researchers interviewed 21,102 people in 21 countries, including more than 1,000 in the UK.