In keeping with established practice, next year's increase is based on retail price inflation (RPI) figures for September this year, but the figure of 5% is unrepresentative of the current climate and should not be used for the April 2009 rise, retailers argue. The RPI fell to 4.2% in October, the biggest fall for five years.
Association of Convenience Stores chief executive James Lowman said: "Government has to stop the 5% increase. As we go into next year and the budget next spring we will be making the case for immediate action on business rates."
A further complication is the pending revaluation of business rates, due to come into force in April 2010, as they were calculated in early 2008 when property prices were much higher.
The British Retail Consortium (BRC) has pointed out that a new "stealth tax" could see local authorities given powers to raise revenues direct from businesses.
The BRC is concerned that the Business Rate Supplementary Bill, which will allow local authorities to impose a supplement of 2p per £1 of rateable value on business properties with a rateable value of over £50,000, must contain sufficient safeguards to ensure that councils use the tax only to fund business-boosting projects rather than general expenditure.
BRC director general Stephen Robertson said: "At a time when retailers are being hit by rising costs and falling sales, the Bill gives local authorities the power to clobber businesses with a hefty new stealth tax. As we head into recession the government should be reducing the burdens on retailers, not compounding them."