The association of socio-economic-demographic (SED; e.g., income-related) factors with depression is widely confirmed in the literature. We conducted a hospital-based case-control study of 160 patients with psychiatrist-diagnosed clinical depression. The control group comprised 160 participants recruited from local communities. We used a questionnaire to collect SED data from all participants. We replaced missing values using multiple imputation analyses and further analyzed the pooled data of five imputations. We also recorded the results from the original analysis and each imputation. Univariate analyses showed income was associated with depression. Multiple logistic regression analyses revealed that, among all SED variables, high income (odds ratio = 2.088 [95% confidence interval = 1.178-3.700]; p = 0.012), middle-level (completed junior or senior high school) education (1.688 [1.042-2.734]; p = 0.033) and cohabitating with four or more family members (1.632 [1.025-2.597]; p = 0.039) were significant predictors for the case group. We conclude that cash income is a determinant of depression in hospital outpatients in Indonesia. This study suggests health policy implications toward better hospital access and service for people with depression in middle- or low-income households, and recommends considering high income as correlated with a high risk of depression, owing to socio-cultural changes.