New business rate valuations have seen 13 employer groups unite in condemning the government's "outrageous" changes.
Other signatories to the letter include the Federation of Small Businesses, Revo, the Association of Convenience Stores, and the British Property Federation.
The next business rates revaluation comes into effect on 1 April but the lobby groups said that tens of thousands of firms still face uncertainty over bills and they want easy access to appeals against "inaccurate" bills that could up to 15 per cent out.
BRC chief executive Helen Dickinson said: "Given the growing burden of business rates, it is essential that each ratepayer pays its fair share. However, the plans for the new appeals process would mean that a business rates valuation determined to be inaccurate by the independent Valuation Tribunal for England, would only be corrected if it is deemed ‘outside the bounds of reasonable professional judgement’.
"This would be unfair to ratepayers and create additional uncertainty for local government. Instead, a collaborative working relationship between the Valuation Office Agency and ratepayers, where information and evidence can be shared and appeals avoided, should be sought."
Business rates are paid on the rental value of the space that businesses occupy varyng in amount depending on the size of the property and what it's used for.
The last time properties were valued, in 2010, almost half of businesses appealed against their bills.