The findings show the need for practitioners to re-evaluate their reliance on the engineer’s estimate. A literature review was conducted to understand the reliance on the engineer’s estimate, and secondary data from Washington State Department of Transportation was used to investigate the reliability of the engineer’s estimate. The research objective was to characterize the engineer’s estimate and allow owners and contractors re-evaluate or affirm their reliance on the engineer’s estimate. This research sought to investigate the reliance on, and the reliability of the engineer’s estimate in heavy civil cost estimate. As such the engineer’s estimate is the benchmark. To the owner, the engineer’s estimate is the basis for funding, evaluation of bids, and for predicting project costs. To the contractor, the engineer’s estimate is the target number to aim for, and the basis for a contractor to evaluate the accuracy of their estimate.