Although 70 per cent describe themselves as good at spelling and think it an important skill, many struggle with common words such as accommodation.
More than 1,000 people, mostly aged between 15 and 21, were asked by researchers at Ulster University to pick out 14 spelling mistakes from a short passage.
Only two identified all the errors, which included "litterature" and "realy". Girls spotted an average of 67 per cent of the mistakes, while boys picked out just over half. The only people in the survey to spot them all were a South African and a West African living in the UK.
In another challenge, the respondents were asked to identify the correct spelling of 24 words from a choice of three, for example "catigory, cattegory and category". In a third of cases, the young people failed to spot the correct word.
Professor Loreto Todd, who carried out the survey for Bloomsbury Publishing, said: "We used everyday words that schools focused on and in one test simply asked people to pick the correct answers. It is not as if we were asking the youngsters to spell 'idiosyncrasy' - we all ought to be able to get 'receive' right."
Last year's national curriculum tests for 11-year-olds showed that more than 600,000 children started secondary school unable to spell words such as pollution, structure or necessary.
The Government's key stage 3 strategy, which schools will use from September, includes a list of more than 700 key words that ministers believe every 14-year-old should be able to spell. The strategy framework advises schools to start English lessons with a 10-minute spelling test.
The researchers say that up to 15 per cent of today's school-leavers may be functionally illiterate. In 1912, the illiteracy rate in the UK was just 2 per cent, according to an HMI report.