Globally, start-up companies receive state support, which is considered to be an investment in future economic growth and regional development. Extensive research consistently demonstrates the efficiency of state aid for newly-established firms. This study adds to the empirical evidence, highlighting the significance and effectiveness of start-up support. An analysis of 112 Latvian supported companies reveals that over half experienced notable improvements in profitability and productivity, often outperforming industry peers at an accelerated rate. The study's findings indicate the importance of the monetary grant’s size: the higher it is, the better productivity and asset profitability results the company achieves after three years of receiving support. These findings emphasize the importance of tailored financial assistance, linking larger grants to enhanced performance metrics. Based on evaluation results and a thorough analysis of scientific literature, the authors present practical recommendations for optimizing the performance indicators of business incubators, providing valuable guidance for policymakers and stakeholders committed to fostering sustainable economic development.