Less than a third of people always check the terms and conditions when sharing their personal information online in return for a service, a payments industry body has found.
Just 31% of people surveyed for Payments UK say they always read the small print when sharing their information to use a service such as price comparison websites, financial services apps, property websites, credit reference agencies, and auction, charity and dating websites.
Payments UK said this "passive approach" lags behind how people manage information about themselves on social media.
Over half (51%) of people surveyed say they always check privacy settings when sharing information on social media accounts.
With advances in technology giving greater control over money management as more people go online to perform day-to-day tasks, Payments UK said customers must have confidence in the way their data is being shared.
The survey of more than 2,100 people across the UK found broad agreement that the way data is used is changing.
Nearly seven in 10 (68%) agree that providing personal information is an increasing part of modern life, while three-fifths (60%) feel there is no alternative.
More than four in five (83%) people expressed concern that some companies share their personal data with other companies.
Maurice Cleaves, chief executive of Payments UK, said: "New ways of storing, sharing and manipulating data have the potential to revolutionise payment services in the UK - offering greater control, convenience and new ways to pay for customers.
"But it is vital that developments in this area put the customer first - the risks around holding and sharing data do not stand still, so customer confidence and trust will be key.
"There is also work to be done to ensure changes don't exclude customers who are unwilling or unable to share their data from these new products and services."