The industry body for UK retailers published a report this week in which it estimated that the cost of implementing the euro in other countries was 0.5% of retailers' annual sales - equivalent to more than £1bn of UK retailers' turnover.
UK retailers face significantly higher costs unless they heed the lesson of these first-wave countries and make extensive plans to handle the changeover, if and when it happens, said David Southwell, head of media at the BRC.
"The key lesson from the first-wave countries was the early planning," he said. "As soon as they were given a changeover date they began looking at systems and processes."
The BRC believes UK retailers will need a period of at least two years before the introduction of euro notes and coins if the changeover is to be managed smoothly.
"The longer that companies have to spread the cost of new systems, the easier it will be," said Southwell. "This is in contrast to Y2K when all the [system] costs came at the same time."
Chancellor Gordon Brown has devised a set of five tests to decide whether the UK will join the euro, which will be assessed by June 2003. If the Government decides the criteria have been met, it will put UK entry to a referendum soon afterwards.