The figures showed that total sales fell by 0.8 percent when compared with August, making it much lower than the 0.1% drop that was expected.
Year-on-year retail growth for Q3 overall was 1.3 percent, which is the weakest rate of annual growth since Q2 in 2013.
This slow growth has been attributed to inflation, as consumers have less disposable income. Inflation was at a five year high of 3 percent in September and is expected to increase a little above that in October.
Kate Davies, ONS senior statistician, said: “September’s retail sales saw a monthly decline of 0.8 percent, reversing August’s growth. However, there is a continuation of the underlying trend of steady growth in sales volumes following a weak start to the year, and a background of generally rising prices.
“These increased costs are reflected in the more rapid growth in the amount spent when compared with the quantity bought.”