Job costing assigns every cost to a specific project and usually to a cost code within it, such as concrete, framing, or electrical. Comparing actual costs with the estimate shows which jobs and activities are on budget, and feeds the estimate-to-complete figures in the WIP schedule.
Accurate job costing depends on disciplined coding of timecards, purchase orders, and invoices. Errors made in the field or the office compound quickly. Automation that suggests job and cost codes from documents, with a person confirming, can reduce rework without losing control.