Financial director Ron Whitten said a 10% increase in operating profit reflected the impact of heavy investment in new sites and technologies.
"Due to the current challenging economic conditions the focus on continuing to provide the best customer service in class, operational efficiency and managing our cost base will remain of vital importance for the foreseeable future," he added.
Last year Henderson Group invested in the redevelopment of 60 stores, recruited 28 new stores and opened its second 'Store of the Future', in Ashbury, Bangor.
Through a combination of energy efficiency measures, the Ashbury store's carbon footprint is 28% less than an equivalent store built three years ago and gives a 22% reduction in energy bills compared to 2006 figures. It is intended as a model for future new-build stores.