While overall shop price inflation held fast at 2.7% last month, non-food declined from 1.4% in August to 1.3% in September, with electrical items in particular, cheaper than the same period last year.
BRC director general Stephen Robertson said of the results: "Shop price inflation is stable and well blow the Consumer Price Index, the Government's official measure of inflation. In fact some goods - clothing and electricals - continue to be cheaper than a year ago, as retailers discount aggressively to produce sales and stay in business."
He added that conditions are unlikely to change much this side of Christmas.
Food inflation, however, remained unchanged at 5% higher than a year ago but is expected to see declines next month in light of Tesco's 'price drop' campaign and a much anticipated supermarket price war.
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