THE growth in online sales in September was at its strongest in 13 years as consumers increasingly use mobile devices to shop, according to new figures.

The online retail market recorded a rise of 13% between August and September, the steepest monthly increase for this period in the 13-year history of the IMRG Capgemini e-retail sales index.

The index was up 20% year-on-year in September, ahead of expectation and driven by the increasing use of mobile devices, according to the report.

The average online shopping basket value reached its highest point since June last year.