The home and hardware retailer reversed a £10.4m loss in 2008-09 with a pre-tax profit of £2.7m.
Like-for-likes dropped 0.5% but in the latest nine-month period showed an improvement of 1%, the retailer's best performance in five years.
Steven Round, chief executive said the improvement followed better buying, more own-brand products, and tight cost control. "We're appealing to a slightly younger customer than we have done traditionally," he said.
Robert Dyas operates almost exclusively in the southeast through 100 stores and expects to open four more this year and refurbish seven.