Businesses have been urged to remember that they are entitled to refuse requests for days off in lieu from part-time staff when bank holidays occur.
According to law firm DWF, bosses can say no to these workers when they ask for extra time off if they do not usually work on Mondays.
The company cites the case of one employee who argued that his employer was discriminating against part-time workers because he was not allowed days off in lieu for public holidays, while those who worked on Mondays were able to get time off.
However, the court ruled that the business was making a distinction between those who work on Mondays and those who do not, rather than basing decisions on whether employees were full-time or part-time.
"While this case will rankle with many part-time workers, it could mean a considerable saving on holiday pay for some employers," commented DWF partner Kirsty Rogers.
Campaigner Graham Smith recently told the BBC that it is likely the government will decide to make St George's Day a voluntary public holiday within the next few years.