In a context characterized by constant technological advancement, where firms are compelled to adapt and innovate their business models to enhance productivity and efficiency, digital transformation emerges as an opportunity. To achieve this, firms typically choose to invest in research and development (R&D), or more broadly, in science, technology, and innovation (STI) activities. This research seeks to analyze the relationship between firms’ R&D expenditure or spending on other science, technology, and innovation (STI) activities and business productivity, measured through firms’ sales. The study employs econometric techniques based on a panel of firm-level data for the period 2012 to 2014. The results suggest that R&D expenditure and other STI activities show a positive correlation with business productivity, in line with the research hypothesis; moreover, the study identifies heterogeneous spatial effects and differences across economic sectors.