It's a nightmare scenario for any shopper. Having browsed for hours through a home decor warehouse, squirmed and twirled in tiny changing rooms, loaded your tray high with a full Irish and pot of tea, or just popped into a lonely service station for baby wipes, you've got to the front of the queue and the end of your tether, and handed over the cash, in the form of a €100 note, only to be told that they're not accepted.

As counterfeiting technology gets more and more advanced, some retailers, especially in high-volume outlets, are becoming reluctant to take large denomination notes. It is a common misconception amongst the public that it is illegal for retailers not to accept these notes, but, according to the Central Bank, they are perfectly within their rights.

"As long as there is a notice clearly displayed within the store, preferably near the till, stating the company policy, then they can do what they like," said a Central Bank spokeswoman.

"If they want to deal solely in fivers, or just coins, and they have a sign up to that effect, then they can do so."

Problems often arise for tourists who arrive from Britain, Europe or the US with large notes. "Countries who were used to larger denominations in their legacy currency, such as Germany or Italy, often have more of these notes in circulation, and people from outside the euro zone are frequently given these notes in bureaux de change in their own country," said the spokeswoman.

Reasons for declining large denomination notes vary amongst retailers. The Body Shop said that often it didn't have enough change and it was a hassle, while one branch of Bewley's explained that, due to the high volume of customers, it was hard to check every note carefully. The Lifestyle sports chain said that it was waiting for new scanners that can read the larger notes.

According to Mr Dermott Jewell of the Consumers' Association of Ireland, not being able to verify the authenticity of notes is just not acceptable.

"We've had quite a few complaints from consumers and this is one of the reasons we have been given by retailers. Quite simply, I was taken aback. If that's the case, the only thing I can say is: 'Why not?' It's about time the system was brought up to speed," he said.

"Consumers should be allowed to change a €100 note, which is, let's be honest, not an earth-shatteringly large amount of money. Although I do appreciate the need for security, with our current price structure, retailers must be ready to be able to accept these notes."

Keeping sufficient change in the till can be a constant source of distress for many retailers and the last thing they want to see is a whole pile of it disappear in exchange for one big note that may or not be counterfeit. Even if they don't have a notice displayed there is little the consumer can do except take the case to the small claims court.

The best advice would seem to be that if you come across a €100 note, or higher, get rid of it as soon as possible.