This study presents empirical evidence of the nexus between social cohesion and climate change adaptation from a tropical cyclone prone coastal district of Bangladesh. The climate change adaptation measure considered here is the reduction of tropical cyclone risk through the improvement of coastal polders. The study exploits a unique policy context and uses household data obtained through a contingent valuation survey asking whether 400 randomly sampled male and female inhabitants would pay a one-off surcharge to co-finance the Coastal Embankment Improvement Project (CEIP)—the centrepiece of the Bangladesh Government's climate change adaptation policy in the coastal zone. A social cohesion index is constructed by summing subjective indicators of trust, mutual co-operation and confidence in collective action. Controlling for a large number of individual, household and community characteristics and village fixed effects, the regression results reveal a significant positive relationship between the social cohesion index and willingness to pay for polder improvement. The study finds a significant welfare benefit of and widespread public support for the CEIP. The mean one-off willingness to pay to support the CEIP varies from US$35 to US$65.