general contractor accounting — 4 profit-bleeding mistakes costing you six figures

Most general contractors lose $150,000+ annually from accounting mistakes they can't even see — WIP schedule errors, overhead misallocation, and expense tracking gaps that bleed profits on every job. This breakdown shows you the exact 4 mistakes that inflate operating costs and the specific fixes that stop the bleeding.

The WIP schedule disaster hiding your real margins

Work-in-progress schedules reveal which jobs make money and which ones don't. But most general contractors build WIP schedules that lie to them every month.

The mistake: General contractors track costs as they pay bills, not as they incur expenses. A $50,000 concrete pour happens in March, but the invoice doesn't get paid until May. Your WIP schedule shows March as profitable and May as a disaster — neither is accurate.

According to the NAHB 2025 Cost Management Survey, contractors who properly accrue unbilled costs report 23% more accurate job margins than those using cash-basis WIP tracking.

The fix requires three changes to your WIP process:

1. Accrue expenses when work is performed, not when invoices are paid
2. Match labor costs to the actual work week, even if payroll runs on different cycles
3. Estimate completion percentages based on cost-to-date plus committed costs, not just what's been invoiced

WIP Method	Margin Accuracy	Time to Generate
Cash-basis tracking	47% accurate	2 hours
Accrual-basis with estimates	89% accurate	4 hours
Real-time job costing	94% accurate	30 minutes

How overhead allocation errors inflate every project cost

Most general contractors spread overhead costs across jobs using revenue percentages or square footage. Both methods create expensive distortions that inflate project costs and skew bidding decisions.

The revenue-based method penalizes high-margin jobs by loading them with overhead they didn't consume. The square-footage method ignores the reality that complex projects require more administrative time, permitting work, and project management hours than simple builds.

The real cost: Overhead misallocation inflates project costs by 15-25% according to AGC's 2025 Financial Benchmarking Report. A $800,000 custom home might carry $40,000 in overhead that actually belongs to your commercial projects.

• Administrative time gets spread evenly instead of tracking actual project demands
• Equipment costs hit jobs that never used the equipment
• Insurance premiums load onto low-risk projects while high-risk jobs get subsidized
• Estimating costs from previous bids get assigned to current jobs

Activity-based overhead allocation requires more setup work but produces margins accurate enough to bid competitively. Salisbury Bookkeeping tracks overhead allocation by job activity for general contractors who need margins they can trust.

The expense tracking gaps costing you $40,000-$80,000 annually

General contractors generate dozens of deductible expenses every month that never make it into their books. Vehicle mileage, client meals, equipment purchases, and subcontractor payments create a paper trail that disappears between job sites and tax time.

The IRS allows construction businesses to deduct vehicle expenses, equipment depreciation, materials storage, and business meals at specific rates. But claiming these deductions requires documentation most contractors don't maintain.

According to the NFIB 2025 Small Business Tax Survey, construction companies miss an average of $47,000 in annual deductions due to inadequate expense tracking systems.

Common expense categories that general contractors miss:

• Vehicle mileage between job sites and supplier visits
• Equipment rental and purchase receipts that never get categorized
• Business meals with clients, architects, and subcontractors
• Professional development and trade association memberships
• Home office expenses for administrative work space
• Cell phone and internet costs for job site communication

The solution requires capturing expenses when they happen, not when you remember them. Mobile expense tracking apps, dedicated business credit cards, and weekly expense reviews prevent deductions from slipping through.

Contract asset recognition mistakes under ASC 606

Revenue recognition rules changed dramatically with ASC 606, but many general contractors still book revenue the old way. The new standard requires recognizing revenue as performance obligations are satisfied, not when payments are received or invoices are sent.

General contractors working on projects longer than 12 months must track contract assets separately from accounts receivable. Contract assets represent work performed but not yet billable under contract terms. Accounts receivable represents amounts billed and owed by customers.

The compliance risk: Mixing contract assets with receivables triggers audit findings and distorts cash flow forecasting. According to the AICPA 2025 Construction Industry Survey, 34% of general contractors still use pre-ASC 606 revenue recognition methods.

The contractors who figure this out stop losing money. The ones who don't keep blaming the weather.

Recognition Method	Compliance Risk	Cash Flow Accuracy
Completed contract	High	Poor
Percentage of completion	Medium	Good
ASC 606 performance obligations	Low	Excellent

ASC 606 compliance requires identifying separate performance obligations in each contract and recognizing revenue as each obligation is satisfied. A custom home contract might contain separate obligations for site preparation, foundation work, framing, and finishing trades.

What accounting method should general contractors use

General contractors over $29.2 million in average annual gross receipts must use accrual accounting under IRS Section 448. Smaller contractors can choose between cash and accrual methods, but the choice affects everything from tax timing to loan applications.

Cash accounting recognizes income when received and expenses when paid. Accrual accounting recognizes income when earned and expenses when incurred. For general contractors with long project cycles, the timing differences create significant impacts on tax liability and financial reporting.

Most general contractors benefit from accrual accounting because it matches revenues with the expenses that generate them. Construction projects span multiple months or years, making cash accounting a poor representation of actual profitability.

• Accrual accounting provides better margin analysis for bid decisions
• Banks prefer accrual-basis financial statements for construction loans
• Bonding companies require accrual accounting for performance bonds
• WIP schedules only work accurately under accrual accounting methods

How general contractors should track job costs

Job costing separates direct costs (labor, materials, equipment) from indirect costs (overhead, administrative, general expenses) to show true project profitability. Without accurate job costing, general contractors can't price future work competitively or identify which project types generate profits.

The foundation of job costing is a consistent chart of accounts that categorizes every expense by cost type and project. Direct labor costs hit specific job numbers. Materials get coded to projects when purchased or delivered. Equipment costs either get charged directly to jobs that use them or allocated based on actual usage time.

Real-time job costing visibility: BuilderCFO is the dashboard we built to give general contractors real-time job cost tracking, WIP schedule updates, and margin-by-project analysis on one screen.

Essential job costing categories for general contractors:

1. Direct labor — wages, benefits, payroll taxes for workers on specific jobs
2. Direct materials — lumber, concrete, fixtures, and supplies delivered to job sites
3. Direct equipment — rental costs and equipment usage charges for specific projects
4. Subcontractor costs — payments to specialty trades working on specific jobs
5. Direct job expenses — permits, inspections, and project-specific costs

Overhead allocation comes after direct costs are captured. Insurance, office rent, administrative salaries, and general equipment costs get distributed across jobs using activity-based methods that reflect actual consumption.

Your next move

Pick one accounting mistake from this breakdown and fix it this month. Don't try to solve all four at once — that guarantees nothing gets finished.

1. Start with your WIP schedule if margins look inconsistent month to month
2. Fix overhead allocation if your project costs seem inflated compared to competitors
3. Implement expense tracking if you suspect you're missing tax deductions
4. Address revenue recognition if you're over $10M annually or work on multi-year contracts
5. Schedule a monthly review process to catch mistakes before they compound

The contractors who fix these accounting mistakes stop losing money on profitable projects. The ones who ignore them keep wondering why their bank account doesn't match their project margins.

This is exactly why we built Salisbury Bookkeeping's fractional CFO service around construction-specific accounting accuracy. General contractors need books that show real job margins, not accounting fiction that hides profit leaks.

Need this handled by someone who does it every day?

Salisbury Bookkeeping is the construction-only bookkeeping + fractional CFO firm that contractors trust to get their books, WIP schedules, and job margins right. And BuilderCFO — our dashboard — gives you real-time job cost visibility, 13-week cash forecasting, and a margin-by-job view in one screen.

See how Salisbury Bookkeeping helps contractors like you → · Try BuilderCFO →