The research highlights the crucial role of trust in social institutions in maintaining social stability, especially during crises. The authors analyze how trust in Ukraine’s key institutions, such as the military, state, and local government, has evolved against existential threats from a 2022 Russian invasion. Factors leading to growth in defense-related institutions and fluctuations in trust in political and judicial institutions are central to the analysis. The paper also discusses the transformative impact of wartime on local governance and civil society, where decentralized efforts have proven essential for resilience and rapid response. Trust in regional institutions and volunteer organizations is critical to community cohesion and effective recovery efforts. The authors conclude that maintaining and strengthening trust in social institutions is vital for post-war reconstruction, citizen engagement, and, ultimately, the ability for peace negotiations. However, the sustainable development of trust requires consistent government reforms, transparency, and public participation, supported by national policies and international partnerships.