The efforts towards the liberalization of electricity markets have sped up recently in some countries within the Association of Southeast Asian Nations (ASEAN) region. This step of opening up the electricity markets is aimed at establishing competitive and efficient electricity markets that not only reduce electricity prices, but also support a sustainable future by reducing carbon dioxide (CO2) emissions from electricity generation and promoting the wider adoption of renewable energy (RE)-based electricity generation. This paper assesses the effects of the electricity market liberalization process in Singapore and the Philippines on these expected outcomes during the period 2015–2020. The regression analysis results suggest that in the specified period, the liberalization of the electricity market in Singapore has delivered both household and industry electricity price reductions and improvement in the RE share. However, there is no significant effect of the electricity market liberalization process on the electricity generated CO2 emissions. For the same period, the results imply that with the electricity market liberalization process in the Philippines, the electricity prices for household consumers and electricity-generated CO2 emissions have increased. Additionally, the liberalization process has no significant impact on both the RE share and industry electricity prices in the Philippines. To overcome the obstacles and strike a balance between the expected outcomes, policy recommendations are given for ASEAN economies following the pathway of liberalized electricity markets.