A remodeling contractor finishes a kitchen job and moves on to the next one. Six weeks later, once the last supplier bills are in and the bookkeeper has reconciled everything, the numbers come through. Labor ran well over the estimate because the old subfloor needed more work than expected, and the extra electrical circuit the homeowner asked for halfway through was never written up as a change order, so it was never billed. The margin the owner was counting on has mostly gone. At year-end, the accountant points out that this type of job has been barely profitable all year.
Nearly every contractor learns a job's real margin eventually, and the trouble is how late that usually happens. Margin discovered after the job is finished can only inform next year's pricing. Seen while the job is running, it tells you when a phase is going over while there's still time to find out why, bill the extra work, adjust the crew or have a conversation with the client.
This article covers the job costing groundwork that has to come first, and what a live job profitability setup does with your estimates, timesheets, supplier bills and accounting system.
What late margin visibility costs
Overruns found after the fact can't be fixed. Unbilled extra work is the most painful version of this, because the work was done and the client would often have paid for it if asked at the time.
Pricing doesn't improve either. If quoted and actual costs are never compared phase by phase, the same estimating errors repeat on every similar job. And cash suffers when overruns surprise the business, because the money has already gone out.
Set up job costing first
Use cost codes, consistently
Break your estimates into a consistent set of cost codes or phases, such as demolition, framing, electrical, plumbing, drywall, finishes and subcontractors. Use the same codes for recording actual costs. If the estimate is one number and the costs are recorded by supplier, there's nothing to compare.
Code every cost to a job
Every hour of labor and every material and subcontractor cost needs a job and cost code. In practice, that means time tracking where crews pick the job and phase, such as the time tracking in Jobber or ServiceTitan or a separate app like QuickBooks Time, purchase orders or job references on supplier orders, and a rule that bills without a job reference get queried before they're entered. QuickBooks Online's projects and Xero's tracking categories or projects can hold the job dimension in your books.
Know your true labor cost
Job costing needs a loaded labor rate: wages plus payroll taxes, insurance, benefits and an allowance for non-billable time. Using bare wage rates makes every job look more profitable than it is. Work this out with your accountant once, and update it annually.
Run a real change order process
Any work outside the original scope should be written up, priced and approved by the client before it's done, then billed. The process can be as simple as a form on the foreman's phone that sends the client a price for approval. Without it, extra work goes unbilled by default.
Agree a weekly review
Decide who reviews job costs and when. A short weekly look at every active job is enough for most small contractors, as long as it actually happens.
What live job profitability does
- Loads the estimate as a budget. When a job is won, its estimate is loaded as the budget by cost code, including any approved change orders.
- Brings in costs daily. Timesheets are converted to cost using your loaded labor rates. Supplier bills and receipts are read, matched to jobs and cost codes using the job reference, the delivery address or the purchase order, and anything uncertain is queued for someone to code. Subcontractor invoices and committed costs from purchase orders are included, so the picture doesn't wait for bills to arrive.
- Tracks progress. The foreman or project manager updates percent complete by phase each week, in a couple of taps.
- Shows each job's position. A dashboard shows every active job's budget, actual and committed costs by phase, the forecast cost at completion and the projected margin.
- Alerts early. When a phase has used more than a set share of its budget before reaching the matching share of completion, the owner and project manager get an alert with the details behind it.
- Catches unbilled extras. Site notes and messages that mention extra work, such as "client asked for an additional outlet in the pantry," are flagged if there's no matching change order, so it can be priced and billed.
- Closes the loop. When a job finishes, a short report compares quoted and actual by cost code. Over time, those reports show which estimates are consistently off, and the price book gets corrected.
The AI work is in matching and reading: coding supplier bills and receipts to the right job, noticing scope changes in site notes, and summarizing why a phase went over in plain language. The budget, the costs and the margin calculation stay plain arithmetic you can check.
That's what our job profit dashboard does, built on your estimates and accounting system. It pairs naturally with the instant quote builder, so the price book learns from every finished job. The construction page shows how the systems connect.
A worked example
Picture the remodeling contractor from the opening, running a kitchen job priced across eight cost codes. Crews clock time to the job and phase in their time tracking app, and supplier orders carry the job number. Two weeks in, the dashboard shows the carpentry phase has used most of its labor budget while the foreman reports it as less than half complete. The alert goes to the owner, who visits the site and finds the subfloor problem. He prices the extra work as a change order the same day, the homeowner approves it on her phone, and the budget updates. A week later, the foreman's site note mentions adding a circuit for the pantry. There's no matching change order, so it's flagged, priced and approved before the electrician finishes. At close-out, the report shows the subfloor allowance in the estimate needs to be higher for houses of that age, and the price book is updated.
What to watch out for
- Coding discipline. Job costing falls apart if time and bills aren't coded. Make coding easy and expected, and follow up on uncoded items weekly so the backlog doesn't build.
- Percent complete. Progress estimates are subjective and tend to be optimistic. Ask for them at the same time each week, and compare them with what the costs suggest.
- Bills that arrive late. Supplier bills can trail the work by weeks. Committed costs from purchase orders and delivery records fill that gap.
- Blaming crews. Overruns often come from estimates, scope or site conditions. Use the data to fix pricing and process, and crews will keep recording time accurately.
- Too many cost codes. A list of eighty cost codes will be coded badly. Ten to twenty meaningful phases are easier to use and still show where money goes.
How to tell whether it's working
Track the share of costs coded to jobs within a week of being incurred, since everything else depends on it. Measure the value of change orders billed each month, the number of overrun alerts, and how many of those led to an action such as a change order or a crew adjustment. On closed jobs, compare quoted and actual margin by job type over time. If the gap narrows, the estimating feedback is working.
Where to start this week
Pick three jobs that finished recently and reconstruct quoted versus actual by phase, as best you can from timesheets and bills. Note where the biggest gaps were and whether any extra work went unbilled. Then agree your cost codes, start requiring a job reference on every supplier order, and put the change order form in your foremen's hands.
Once costs are being coded to jobs and phases consistently, a live view of each job's margin is a short step away, and the owner finds out about the subfloor problem while the job is still on site and the client is still there to talk to.
The free PATH report gives you a quick read on where job costing sits among the other jobs worth automating in your business. If you'd rather talk it through, book a call.