Construction job costing means tracking every cost — labor, materials, equipment, and subcontractors — against the specific job it belongs to, not just against a general ledger category. Without it, a contractor's overall P&L can show a healthy profit for the year while several individual jobs quietly lost money, because overruns on the bad jobs get buried inside gains on the good ones and nobody ever isolates which is which.
The foundation is a cost-code structure inside QuickBooks: dedicated codes for labor, materials, equipment, and subcontractor costs on every active job, so a project manager can pull budget-vs-actual for a single job at any point, not just at close-out. Contractors bidding future work off a chart of accounts that only shows company-wide totals are effectively bidding blind — they have no real data on which job types or clients are actually profitable.
Work-in-progress (WIP) accounting is the other half of the picture, and it's where a lot of contractor bookkeeping quietly breaks down. A WIP schedule calculates percent complete, earned revenue, and — critically — whether each job is over-billed or under-billed relative to the work actually performed. Underbilling means the contractor is unknowingly financing the job out of pocket; overbilling inflates apparent cash position while masking a liability that comes due as the job wraps up.
Retainage adds a real cash-flow trap on top of this. Owners commonly withhold 5–10% of every progress payment until a job is complete or a warranty period passes, and contractors running several jobs at once can end up with a large amount of cash tied up in retainage receivables they aren't actively tracking or chasing. Retainage needs its own line on the books, aged like any other receivable, not buried inside the job's general revenue.
1099 subcontractor compliance is the piece that turns into a January scramble without a system running all year. Every new subcontractor should be enrolled in a W-9 workflow before the first payment goes out, flagged for 1099 tracking in QuickBooks from day one, and — depending on the jurisdiction and contract — lien waivers collected before releasing payment. Reconstructing this at year-end across dozens of subs is where per-form IRS penalties and lien exposure both show up.
None of this replaces your CPA's guidance on which revenue-recognition method — percentage-of-completion or completed-contract — is right for your business; that's a tax and GAAP decision made with your CPA, not a bookkeeping call. What good job-cost bookkeeping does is make sure the underlying data — job-level actuals, WIP status, retainage aging, and 1099 records — is accurate and current, so that decision (and your bonding agent's and lender's review) is based on real numbers.
Our team sets up and maintains construction-specific chart of accounts, job-cost coding, monthly WIP schedules, and retainage tracking, with 1099 compliance handled throughout the year rather than reconstructed in January. If you want to see which of your active jobs are actually making money, a discovery call is the fastest way to find out.
Frequently Asked Questions
What is job costing in construction bookkeeping?
Tracking labor, materials, equipment, and subcontractor costs against each specific job rather than only company-wide totals, so you can see real-time budget-vs-actual and true profitability per job.
What does a WIP schedule tell a contractor?
It calculates percent complete and earned revenue for each job and flags whether you're over- or under-billed relative to work actually performed — underbilling means you're financing the job yourself without realizing it.
How should retainage be tracked?
As its own aged receivable line, separate from ordinary job revenue, so you know exactly how much cash is tied up and can actively track when it's due.
Can you help with 1099 compliance for subcontractors?
Yes. We enroll subcontractors in a W-9 workflow before the first payment, flag every vendor for 1099 tracking in QuickBooks, and deliver ready-to-file 1099 data to your CPA well before the deadline.