Our paper aims to identify the most important factors determining companies’ decision to invest in the energy transition in Algeria. Energy transition has been many governments’ main topic of interest over the last decades, climate change has led many of them to establish long-term plans for a successful energy transition; these plans aim to reduce greenhouse gas emissions following the guidelines of the COP21. Through a quantitative approach, we have addressed a questionnaire to different companies operating in Algeria and have obtained a total of 117 responses. The results show that financial, technical and regulatory factors have minimal impact on companies’ decision to invest in renewable energy and energy efficiency in Algeria. Further studies should explore other investment factors to help accurately determine those that significantly impact companies’ decisions to invest in Algeria’s renewable energy and energy efficiency. Furthermore, targetting one sector at a time and exploring the alternatives of foreign direct investment in renewable energy can result in higher efficiency.