The purpose of this study is to extend knowledge about the role of accelerators for internationalizing edtech start-ups. Accelerator networks are considered mechanisms that enable start-ups to embed in the edtech sector during the parallel process of venture creation and international opportunity development. A single case study was conducted to examine the phenomenon holistically. The research site was an accelerator in the emerging Finnish edtech sector. The extensive data consists of 46 interviews, observations and documents. The interviews include entrepreneurs from start-ups, accelerator managers and representatives from accelerator networks and the edtech sector. The method of analysis was the constant comparative method, which has been used in previous studies to analyze entrepreneurial networks. The findings determine that an accelerator may facilitate versatile local and international sector-specific partner networks, which contribute to the development of international opportunities. The findings emphasize the importance of co-creation and internationalization partners. Furthermore, the findings display international opportunity development through formal and informal networks, tangible and intangible resources and collaboration with open and pre-determined goals. The study explains the role of accelerator networks in the international opportunity development of start-ups. By addressing the particular features of start-ups and the newness of the ventures, this study enriches the discussion on international opportunities.