Start by pulling a job cost report for every active project. The report needs to show your original budget alongside actual costs incurred through month end, broken down by cost code. At a minimum you want labor, materials, subcontractors, equipment, and overhead as separate line items. If your accounting software only shows total costs per job without that breakdown, your chart of accounts or job structure needs attention before the reconciliation will tell you anything useful.

Calculate the variance for each cost code on each project. Budget minus actual gives you the dollar amount. Divide that by the budgeted amount and you get a percentage. Both numbers matter. A $3,000 overrun on a $15,000 framing budget is a 20% problem worth investigating. That same $3,000 on a $400,000 total project budget barely moves the needle. Focus your energy on line items where the dollar variance is large enough to affect the project or where the percentage is trending the wrong direction month over month.

Now factor in committed costs. These are purchase orders and subcontracts you’ve signed but haven’t been fully invoiced for yet. Your actuals might show $40,000 spent on electrical, but if the subcontract is for $95,000, you have $55,000 in committed costs sitting off your report. Add committed costs to actual costs for each cost code and compare that total against the budget. That is your real position on the job. Skipping this step is exactly how contractors get blindsided by overruns they should have seen coming two months earlier.

Update your cost-to-complete estimate for every cost code. This is not just budget minus what you’ve spent. That is a math exercise, not an estimate. Cost-to-complete is your honest assessment of what it will take to finish the remaining work given what you know today. If material prices jumped since you bid the job, your remaining materials cost is not what the original budget says. If you added scope through a change order that hasn’t been formalized yet, that cost needs to show up somewhere. Good financial data across any industry, whether you need healthcare practice bookkeeping services or construction financial reporting, depends on honest inputs. Lazy cost-to-complete estimates make the entire process a waste of time.

Once you have actual costs, committed costs, and estimated cost-to-complete for each cost code on every project, you can build your WIP schedule. The WIP (work in progress) schedule compares your cost completion percentage against your billing percentage on each job. It tells you whether you’ve overbilled or underbilled. For contractors using percentage-of-completion accounting, the WIP directly determines how revenue gets recognized on your financial statements. An inaccurate WIP means inaccurate financials, which means decisions based on wrong numbers.

Do this for every active project, not just the large ones. A $50,000 job that runs 30% over budget hurts your bottom line just as much as a large job running 5% over. Set a recurring date within the first week after month end so the numbers are still fresh and you haven’t moved too far into the next billing cycle.

The tools matter but the discipline matters more. QuickBooks Online can handle job cost reporting if your accounts and project structure are configured correctly. Construction-specific platforms like Sage or Procore handle it more naturally. Whatever you use, the data going in has to be accurate. Every subcontractor invoice, every timecard, every material receipt needs to hit the right job and the right cost code during the month. If your team is sloppy about coding transactions as they happen, no amount of month-end analysis will fix it.

If this process feels overwhelming or you keep finding errors in your reports, working with someone experienced in construction job costing can prevent expensive surprises. Getting budget-to-actual reconciliation right each month is what separates contractors who control their margins from those who discover they lost money after the project is already closed out.