This study attempts to enhance our understanding of the inconsistencies reported in the literature concerning the relationship between work overload and work outcomes. We tested the proposition that work overload should be divided into two constructs based on its source: self-initiated overload (SIO), and organization-imposed overload (OIO). Based on the work stress and job crafting literatures, we expected that SIO and OIO would tend to relate differentially to the work outcomes of job satisfaction, emotional exhaustion, work–family conflict, job performance, and helping organizational citizenship behaviours. A study was conducted using three samples, the first consisting of full-time employed students in three countries (N = 116), the second consisting of the nursing staffs of six private hospitals in Switzerland, and the third consisting of 161 middle manager–supervisor dyads in Switzerland. Two different measures of SIO and OIO were used. SIO was found to have a more beneficial relationship with the work outcomes than OIO, general supporting our hypothesis. Theoretical and practical implications are discussed.