More than one third of adults are unable to answer basic questions about savings, the cost of a loan and tax, according to research.
Over 2,000 adults from all walks of life were tested by the Open University Business School (OUBS) on questions of a GCSE level, which involved them making calculations to work out items such as which savings accounts paid the most.
Across all seven multiple choice questions they were asked, an average of 41% of adults were unable to come up with the right answer.
Just 3% of people questioned managed got all seven questions correct - the same proportion of people who got one question right out of seven.
More top news
Northwestern Scotland and Northern Ireland face a rain-hit weekend, while the rest of Britain enjoys some bright but generally dry weather.
All this week while reporting, I have been taking photos. They offer powerful portraits of the lives affected by the desperate outbreak.
Some of the world's biggest football clubs will ask FIFA to move the 2022 World Cup to spring.