Urban vulnerability to climate change is intensifying food security challenges in developing countries, yet the translation of climate awareness into adaptive behavior remains poorly understood. This study examines the determinants of climate change adaptation and quantifies the awareness–behavior gap in Benin City, Nigeria. Using cross-sectional survey data from 150 respondents, composite indices were developed for awareness, socio-demographic characteristics, and adaptation behavior. Empirical analysis employed descriptive statistics, Pearson correlation, Ordinary Least Squares (OLS) regression, and a negative binomial model for robustness, alongside reliability and validity testing (Cronbach’s alpha, EFA, CFA). Results indicate that both awareness (β = 0.208, p = 0.001) and socio-demographic factors (β = 0.272, p = 0.001) significantly influence adaptation behavior, explaining 20.6% of outcome variability. Robustness checks confirm consistency across model specifications. However, a paired sample t-test reveals a large and statistically significant awareness–behavior gap (t = 11.01, p < 0.001; Cohen’s d = 0.90), demonstrating that high awareness does not proportionately translate into adaptive action. The findings suggest that adaptation is constrained by structural and socio-economic barriers beyond cognitive awareness. This study advances empirical understanding by integrating behavioral gap analysis with multivariate modeling in an urban African context. Policy efforts should move beyond awareness campaigns to incorporate targeted socio-economic and institutional interventions that enable actionable adaptation and enhance urban food system resilience.