The Association of Convenience Stores (ACS) and the Scottish Federation of Grocers are among those that have joined to call for an end to the traditional practice of retail landlords demanding three-months rent in advance. Fifty-one MPs have also signed an Early Day Motion to the same effect.
The BRC said the practice adds a further£145 million to retailers' costs and is at odds with standard business practice.
BRC director-general Kevin Hawkins said: 'The growing scale of support for the campaign indicates the pressure retailers of all sizes are under. At a time when they are being squeezed by rents and rates, service adds an extra burden they could do without.'
British Hardware Federation managing director Alan Hawkins added: 'Paying three months up front creates real cash-flow difficulties for our businesses, particularly the smaller ones. Imagine being paid weekly or monthly and having to pay three months of your mortgage in one go.'
The campaign has already received backing from several major retail chains, including Next, Dreams and Travis Perkins.
The BRC also plans to launch a new standard later this year to recognise landlords who offer more retailer-friendly terms.