Job costing is the discipline of tracking every cost on a specific project — labor, materials, subcontractors, equipment, and overhead — against the approved estimate, organized by cost code. The purpose is to know, at any point during construction, how much of the budget has been spent, how much is committed, and how much remains. Job costing is distinct from accounting: accounting records what has been paid; job costing records what has been spent and obligated, regardless of payment timing. Without job costing, a project’s financial position is unknown until the final invoice, at which point nothing can be done about overruns. With job costing, overruns are visible while there is still time to respond to them.