The urgent challenge of climate change, driven by human activities, necessitates a coordinated international response to mitigate its impacts and advance towards a sustainable future. The political and institutional frameworks within countries significantly influence the effectiveness of climate policies, as evidenced by variations in annual CO2 emissions. Studies indicate that democracies with strong public involvement and governance are more adept at enacting efficient environmental measures. However, authoritarian regimes favoring rapid policy execution may deprioritize environmental goals for political stability, impeding holistic climate mitigation efforts. In this context, the role of our audience, consisting of academic researchers, policymakers, and environmentalists, is crucial in understanding and addressing these challenges. This study examines the impact of institutional governance, European Union (EU) membership and the level of economic development on climate change mitigation. By drawing on data from the V-Dem database and World Governance Indicators (WGI), encompassing 10 Balkan countries, divided into EU members, Bulgaria, Croatia, Greece, Romania, Slovenia, and non-EU members Albania, Bosnia and Herzegovina (BiH), North Macedonia, Montenegro, Serbia, this research probes the impact of political and institutional factors on CO2 emissions from 1998 to 2022. Additionally, by integrating the Environmental Kuznets Curve (EVC) hypothesis, the correlation between economic growth and environmental degradation is elucidated. This study uses Inverse Probability Weighting (IPW) regression in the context of estimating the Average Treatment Effect (ATE) to evaluate the differences in CO2 emissions depending on whether a Balkan country is part of the European Union) or not. Through a comprehensive review of existing literature, this study uncovers notable disparities in CO2 emission patterns and the effectiveness of environmental policies between EU and non-EU Balkan nations. Empirical evidence supports the proposition that EU membership is pivotal in bolstering climate mitigation efforts through policy frameworks and improvements in governance quality. The amalgamation of empirical findings and literature review suggests that EU membership impacts Balkan countries’ climate change mitigation strategies, with EU members demonstrating substantial strides in CO2 emission reduction. This study emphasizes the importance of institutional governance and environmental policy implementation in tackling climate change. It demonstrates how EU integration encourages stricter regulations in Balkan states and calls for detailed research on policy interventions and outcomes. The paper offers insights into the effect of EU membership and political and institutional backgrounds on climate resilience, which is valuable for policymakers and scholars of the field.