Retailers who wish to contest their business rates over the past five years have until March 31 to submit their appeal.

Those looking to challenge the rate they have been paying since April 1, 2005 must contact the Valuation Office Agency (VOA) before March 31 at, or by calling 03000 500 270.

An appeal can be made if a retailer believes that they have been paying a higher rate than neighbouring properties, or if there has been a material change in circumstances such as the street being closed due to roadworks, or a high proportion of empty shops nearby.

According to the Forum of Private Business (FPB), more than 160,000 small businesses have already successfully appealed against the 2005 rates.

The FPB also advised retailers looking to appeal against their 2010-2015 rates to watch out for "cowboy" ratings surveyors offering to reduce rates while charging extortionate fees.

"This is a problem that comes about every five years after the rate revaluations have been carried out," said FPB service representative Philip Moody. "These cowboys spring up and start cold-calling businesses offering big reductions. However, it's often the case that savings are minimal and are quickly dwarfed by the fees they charge."

The FPB advised checking a surveyor's success rate, not to pay upfront and to examine contracts for hidden charges.

Association of Convenience Stores public affairs director Shane Brennan also called for caution when seeking advice.

"Retailers should ensure they use only approved providers," he said. "Many claim they will not charge unless the appeal is accepted, but in fact all appeals are accepted. Remember the old adage: if it looks too good to be true, it probably is."