Job costing is one of those terms that gets used for everything from "I write down materials" to enterprise GL coding. For small contractors, the goal is simpler: know, at any point in the job, whether you're going to make money on it.
The four cost buckets that actually matter
You can run accurate job costing with four categories. Anything beyond this is usually accountant-pleasing, not contractor-helping.
- Materials — every receipt for stuff that ended up on the job. Tag it to the job, ideally to a budget line.
- Labor — hours worked on the job by you, your crew, or anyone on the W-2 / 1099 list, multiplied by your fully-burdened rate.
- Subs — every sub invoice tied to this job. Include retention if you hold it.
- Other direct costs — dumpster fees, permits, equipment rentals, deliveries. Anything that wouldn't have happened without this job.
What to skip
Overhead allocation, depreciation, indirect labor, fully-loaded shop hours — these belong in your end-of-year accounting, not your real-time job costing. Trying to track them at the job level just slows everything down.
Track estimated vs. actual, by line
The most useful single view in construction is estimated vs. actual for each line of the budget. It tells you not just "is the job over" but "where" — so you can fix the problem before it eats the whole margin.
See job costing in SiteView for how that view works in practice.
Capture costs where they happen
Job costing fails when capturing the data is hard. The receipt in the truck doesn't help anyone. The receipt photographed and tagged to a job updates the budget that afternoon. That's the whole game.
Your tools should let you log expenses from the field, attach a receipt photo, and tag them to a project and budget line in under thirty seconds — see daily logs for the field-side workflow.
Update the budget when scope changes
A change order without a budget update is a memory test. Every approved change should adjust both the contract value and the relevant cost lines, automatically. See change orders.
Watch margin, not just variance
Variance tells you what went over. Margin tells you whether you're still going to make money. The right job costing view shows both — current margin, projected margin at completion, and the lines pulling the number down.
The honest tradeoff
Strict job costing takes 5–10 minutes a day if you stay on top of it. That's the price. The contractors who do it well will tell you it's the single highest-ROI habit in the business.