This research provides an analysis of the relationship between preliminary estimate, tender sum and final account of building projects with a view to predicting final account accurately from tender sum and preliminary estimate. To achieve the objectives, the study carried out extensive review of literature and collected data interviews and administration of structured questionnaires. The data collected were analysed using multiple regression, correlation matrix and frequency distribution. The research reveals that there is a significant relationship between preliminary estimate, tender sum and final account of building projects.