The project was set up to investigate “Budgetary control: A managerial tool for effectiveness and efficiency of an organization a case study of Guaranty Trust Bank Plc Uyo”. The objective of this study was to critically analyze the important of budgetary control and effect for effectiveness and efficiency in the banking sector of the economy. It is imperative to note that budgetary control is an essential tools for effective planning in any organization especially in the banking sector. Although lack of dynamic structure as well as training of financial employees to become professional in the banking sector is being sported out as the constraint in the sector, effort should be made to contain this for effective growth and sustainability of this sector. The sample size of this study was 60 as population of staff in Guaranty Trust Bank Plc Uyo, four research question were formulated and three hypothesis was tested. The instruments for data collection were questionnaire, personal interview text books, data collected were analyzed using percentage for research questions and correlation for hypothesis. Based on the findings, recommendation were made on budgetary control: A managerial tool for effectiveness and efficiency of an organization.