Team effectiveness and strategic planning has been individually researched on organisational performance but combining the two together is rare, especially in the banking industry in Nigeria. The present study attempted to fill his gap. Using a cross-sectional survey design with team effectiveness and strategic planning as independent variables, the researchers administered questionnaire, containing team effectiveness scale, strategic planning scale and organisational performance scale, to a randomly selected participants among some banks employees in south west Nigeria, who were willing to participated and actually participated in the study. A total of 113 participants were actually used. Regression analysis revealed that team effectiveness is significantly and positively related to organizational performance. Strategic management was found to significantly predict organizational performance. Findings revealed the importance of team effectiveness and strategic management to organizational success, especially within the banking industry. It was recommended that managers and stakeholders regularly assessed teams and provide necessary support to ensure optimal performance. Findings were discussed using relevant literature and empirical findings.