Retainage and WIP Schedules: Reading a Work-in-Progress Report and Spotting Overbilling Before Your Banker Does

A construction company can appear profitable on its income statement while individual jobs are quietly losing margin. A well-maintained WIP schedule exposes that risk by comparing estimated costs, actual costs, earned revenue, billings, retainage, and projected profit job by job.

That is why a construction work in progress report matters far beyond the accounting department. Owners use it to understand whether jobs are making money. Project managers use it to catch cost overruns. 

Controllers use it to support revenue recognition and financial reporting. Lenders and sureties may use it to judge whether reported profits, working capital, backlog, and job estimates appear credible.

A good construction WIP schedule also separates concepts that are often confused. Profit is not the same as cash. Billings are not automatically revenue. Retainage is not immediately available cash. A large invoice does not necessarily mean the contractor has earned the same amount, and a profitable job can still consume substantial working capital.

The challenge is that a WIP report is only as reliable as the information feeding it. Missing subcontractor invoices, stale cost estimates, unsupported change orders, inaccurate labor coding, or unrealistic cost-to-complete forecasts can make a healthy-looking job much weaker than it appears.

This guide explains how to read a WIP report, account for retainage, identify construction overbilling and construction underbilling, evaluate job profitability, and spot problems before outside financial users do.

The discussion is educational and general in nature. Exact construction accounting treatment depends on the reporting framework, accounting method, contract terms, company policies, tax elections, and guidance from the contractor’s CPA or other professional advisers.

What Is a Construction WIP Schedule, and Why Does It Matter?

A construction WIP schedule is a job-by-job financial report that compares each contract’s expected value and cost with work performed, costs incurred, revenue recognized, amounts billed, and projected profit.

The purpose is not simply to list unfinished projects. Construction WIP accounting tries to answer a more useful question: Based on what has actually happened on each job, how much revenue and profit should the company reasonably recognize, and how does that compare with what has been billed?

For contractors reporting under U.S. GAAP, revenue recognition may fall within ASC 606, Revenue from Contracts with Customers. Under ASC 606, revenue may be recognized over time when the applicable criteria are met, and a contractor using an input method may measure progress using inputs such as costs incurred relative to expected total costs. 

The specific method must faithfully depict performance and be applied in accordance with the relevant accounting guidance. FASB’s ASC 606 resources provide the authoritative starting point.

Internal WIP management, however, should not be confused with GAAP financial reporting or tax accounting. A contractor may use a cost-to-cost WIP report every month for operational management while its tax return follows different rules under the Internal Revenue Code. 

Likewise, management’s job-cost report may contain operational measures that do not correspond exactly to financial-statement classifications.

A well-maintained WIP report in construction helps management evaluate:

• construction job profitability;
• whether estimates remain realistic;
• cost overruns and margin erosion;
• billing position;
• retainage exposure;
• approved and pending change orders;
• remaining work and committed costs;
• contract backlog;
• projected construction cash flow;
• large or unusual loss jobs; and
• whether job-level information agrees with the accounting records.

These issues matter to outsiders as well. A lender considering a contractor’s creditworthiness may look beyond total revenue and net income to the quality and timing of cash flow, receivables, working capital, and project performance. 

SBA materials, for example, emphasize repayment ability and note that certain working-capital borrowers must be capable of producing timely and accurate financial information. Specific bank underwriting requirements vary significantly by lender and facility.

Sureties may also request detailed contractor financial information when evaluating bonding capacity. They may consider backlog, working capital, net worth, job concentration, historical performance, WIP quality, and management’s ability to estimate projects accurately. None of these metrics guarantees bonding approval by itself.

For contractors trying to strengthen the underlying data, construction KPI and job-cost dashboards can help connect estimated, committed, actual, and cost-to-complete information instead of relying only on month-end accounting totals.

Key Columns in a Construction Work in Progress Report

Different contractors and accounting systems use different layouts, but most useful retainage and WIP schedules contain the same economic building blocks.

Understanding those fields is the first step if you want to read a construction WIP schedule intelligently.

WIP Field	What It Means	What to Watch
Contract value	Current supported value of the job, generally including appropriate approved changes	Unsupported or duplicated change orders
Estimated cost	Current forecast of total cost required to finish	Stale estimates or optimistic assumptions
Cost to date	Recorded project costs incurred through the reporting date	Missing invoices, miscoded labor, delayed costs
Percent complete	Measure of project progress under the selected method	Whether the calculation reflects actual performance
Earned revenue	Revenue attributable to performance through the reporting date	Inconsistent assumptions or unsupported progress
Billings	Amount invoiced to the customer to date	Billing delays, front-loading, disputed invoices
Over/underbilling	Difference between earned revenue and billings	Large or persistent unexplained balances
Retainage	Contract amounts withheld until specified conditions are satisfied	Aging, collectibility, closeout delays

• Contract amount and revised contract value: Start with the signed agreement. Then identify approved change orders and other contract modifications that are appropriately included under the company’s accounting policies and applicable reporting framework. A project that started at $2 million may now be a $2.3 million job, but the additional $300,000 should have documentary support.
• Estimated total cost: This is management’s current forecast of what the entire job will cost, not simply the original estimate. It should reflect information available today, including known labor inefficiency, committed subcontract costs, material exposure, equipment, expected closeout costs, and other relevant project costs.
• Cost incurred to date: This represents project costs recorded through the reporting date according to the company’s job-cost system and accounting policies. Good construction job cost reporting depends on consistent coding of labor, materials, subcontractors, equipment, and any appropriately allocated costs.
• Estimated cost to complete: Conceptually:

Estimated Cost to Complete = Current Estimated Total Cost − Cost Incurred to Date

Suppose a job is expected to cost $800,000 and $500,000 has been incurred. The remaining estimated cost is $300,000.

That calculation is mathematically simple. Estimating the $800,000 total correctly is not.

• Percent complete: A common cost-to-cost approach compares costs incurred with expected total costs:

Percent Complete = Costs Incurred to Date ÷ Estimated Total Cost

If recorded costs are $500,000 and estimated total cost is $800,000:

$500,000 ÷ $800,000 = 62.5%

The result says that, using cost as the measure of progress, the job is 62.5% complete.

That does not mean the project manager necessarily sees 62.5% of physical construction complete. Cost-based progress and physical progress can diverge, particularly when significant materials are purchased early or when particular costs do not proportionately depict performance. 

The accounting team should follow its applicable revenue-recognition policies rather than mechanically applying the formula to every cost.

• Earned revenue: In a simplified cost-to-cost example:

Earned Revenue = Revised Contract Value × Percentage Complete

If the revised contract is $1,000,000 and calculated progress is 62.5%, conceptual earned revenue is $625,000.

This example illustrates WIP mechanics; actual ASC 606 accounting requires consideration of the performance obligation, transaction price, contract modifications, measure of progress, and other applicable requirements.

• Estimated gross profit: The expected profit on the entire contract is:

Estimated Gross Profit = Contract Value − Estimated Total Cost

For a $1,000,000 contract expected to cost $800,000:

$1,000,000 − $800,000 = $200,000 estimated gross profit

The corresponding estimated gross margin is:

Estimated Gross Margin % = Estimated Gross Profit ÷ Contract Value × 100

So:

$200,000 ÷ $1,000,000 = 20%

When the estimated cost changes, expected gross profit changes immediately. That is one reason cost-to-complete reviews have such a strong effect on construction financial statements.

Estimated Cost to Complete: The Number That Deserves the Most Scrutiny

Estimated cost to complete may be the most judgment-sensitive number in a construction WIP schedule.

Costs already recorded are historical. Billings already issued can be verified. The signed contract exists. But the remaining cost is a forecast, and the forecast determines both projected profit and, under a cost-to-cost model, the percentage of completion.

Suppose the same $1 million job has $500,000 of cost incurred. If the estimated total cost is $800,000, the project appears 62.5% complete and has an estimated $200,000 total profit.

If management learns that another $150,000 of labor, rework, and subcontractor costs will be required, total expected cost rises to $950,000. The project is now only about 52.6% complete using the simplified cost-to-cost calculation, and expected gross profit falls to $50,000.

Nothing about the signed contract changed. What changed was management’s understanding of what it will cost to fulfill it.

Cost-to-complete warning signs include:

• an estimate that never changes despite documented project problems;
• outstanding subcontractor commitments omitted from forecasts;
• materials ordered but not reflected in remaining-cost assumptions;
• delayed vendor or subcontractor invoices;
• labor hours running above budget with no forecast adjustment;
• expected equipment rental overruns;
• missing supervision or project-management costs where applicable;
• forgotten testing, commissioning, punch-list, or closeout costs; and
• subcontractor claims that management knows are likely to create additional cost.

A project can look artificially profitable when remaining costs are understated even without intentional manipulation. Slow information flow is enough to create the problem.

For a complementary estimating perspective, see How to Price Construction Jobs Accurately, which discusses comparing budgets, actual costs, and historical project performance.

Retainage, Overbilling, and Underbilling in Construction

Three WIP concepts create a large share of contractor confusion: retainage, overbilling, and underbilling. They are related to billing and cash flow, but they describe different things.

What Is Retainage?

Retainage is a contractual amount withheld from a contractor’s progress payments, usually until specified milestones, substantial completion, final completion, or other contractual conditions are satisfied.

A general contractor may also withhold retainage from subcontractors when the applicable subcontract and law permit it. State laws and public-project rules can affect retainage practices, so contract and legal requirements should be reviewed separately from accounting treatment.

Retainage receivable generally refers to amounts customers have withheld from amounts otherwise associated with the contractor’s work. It is economically different from an ordinary past-due invoice because payment may depend on completion, acceptance, release documentation, or another contractual condition.

Retainage payable refers to amounts the contractor has withheld from subcontractors or vendors where applicable. It represents an obligation to the downstream party, subject to the relevant contractual conditions and other requirements.

For financial reporting under ASC 606, classification requires more than simply putting every retained amount in accounts receivable. 

FASB staff educational materials explain that whether retainage is presented as a receivable or within a contract asset or contract liability depends in part on whether the right to consideration is unconditional. Contract presentation is evaluated under Topic 606 rather than by using a one-size-fits-all “retainage receivable” label.

From a management perspective, the WIP schedule may still show retainage separately because it is highly relevant to cash planning and collection.

A contractor could have $600,000 of recognized revenue and $570,000 of gross progress billings but only $513,000 currently due because $57,000 has been withheld as retainage. That retained amount contributes to economic value but cannot be treated as immediately spendable cash.

Retainage deserves additional attention when:

• balances are old;
• final completion has been delayed;
• required closeout documents are incomplete;
• the owner disputes work;
• liens or claims complicate release;
• punch-list work remains substantial; or
• collection depends on another party receiving payment.

What Is Overbilling?

Overbilling generally occurs when billings to date exceed earned revenue in the internal construction WIP analysis.

Conceptually:

Overbilling = Billings to Date − Earned Revenue

Suppose a contractor has earned $625,000 on a job but has billed $700,000.

$700,000 − $625,000 = $75,000 overbilling

Overbilling is not automatically bad and does not by itself imply misconduct.

Legitimate overbilling may result from:

• favorable contract billing terms;
• mobilization payments;
• properly authorized deposits;
• front-loaded scheduled values permitted by the contract;
• early material billing when contractually allowed; or
• normal timing differences between invoicing and accounting recognition.

From a construction cash flow perspective, being appropriately ahead on billing can be helpful because the contractor is not financing every dollar of project cost from its own working capital.

The risk comes when today’s advanced cash must pay for substantial future work.

If the company treats excess billings as profit available for unrelated spending, distributions, or another project, the original job may later experience a cash squeeze. The contractor still has an obligation to perform the remaining work.

Potential warning signs include large overbilling relative to remaining work, falling margins on an overbilled job, declining company cash despite advance billing, unsupported front-loading, unresolved change orders, and weak documentation supporting the estimated cost to complete.

The combination matters more than the overbilling balance alone.

What Is Underbilling?

Underbilling generally occurs when earned revenue exceeds billings to date in a construction WIP analysis.

Conceptually:

Underbilling = Earned Revenue − Billings to Date

Suppose earned revenue is $625,000, but the contractor has billed only $550,000:

$625,000 − $550,000 = $75,000 underbilling

Persistent construction underbilling deserves investigation because the company may be financing work before collecting from its customer.

Possible causes include:

• missed billing milestones;
• slow invoice preparation;
• unapproved or unresolved change orders;
• incomplete supporting documentation;
• billing disputes;
• contract restrictions;
• poor project administration;
• delayed quantity approvals;
• work performed outside the agreed billing schedule; or
• inaccurate WIP assumptions.

Underbilling can also indicate an accounting problem rather than a billing problem. If estimated total cost is understated, a cost-to-cost model may make the job appear further complete than it really is, inflating calculated earned revenue and creating an apparent underbilling.

That is why the proper question is not simply, “Why haven’t we billed this?” Management should ask whether the earned-revenue calculation itself is supported.

Condition	Billings vs. Earned Revenue	Possible Meaning	Main Risk
Overbilled	Billings exceed earned revenue	Favorable timing, deposits, mobilization, front-loaded contractual billing	Future work may consume cash already collected
Underbilled	Earned revenue exceeds billings	Billing delay, unresolved changes, contractual restrictions, or WIP-estimate issue	Contractor finances work and strains working capital
Roughly aligned	Billings and earned revenue are relatively close	Billing generally follows measured performance	Other job risks can still exist

Underbilling Is Not the Same as an Unbilled Change Order

Underbilling and unbilled change orders can overlap, but they are not interchangeable.

An underbilling is a difference between recognized or calculated earned revenue and billings. An unbilled change order is a project-administration issue involving additional scope that has not yet been billed, often because authorization, pricing, documentation, or contractual prerequisites remain unresolved.

Management should distinguish among approved change orders, pending change orders, and disputed change orders. Increasing contract value or projected profit for uncertain changes can make a WIP report appear stronger than its support warrants.

ASC 606 contains specific guidance for contract modifications, variable consideration, and transaction price. The accounting conclusion therefore depends on the facts rather than the project team’s expectation that the customer will “probably approve it.”

A disciplined WIP review should separately track the expected revenue effect, expected cost effect, approval status, documentation, and billing status of each significant scope change.

Profit Fade, Profit Gain, and the WIP Schedule Example

A WIP schedule is most valuable when it shows not only the current projected margin but how that projection has changed.

Profit fade means expected job profitability deteriorates as the project progresses. A job originally forecast to earn $300,000 may now be expected to earn $180,000 because estimated costs increased or recoverable contract value fell.

Common causes include:

• an inaccurate original estimate;
• labor productivity below assumptions;
• material cost increases;
• rework;
• subcontractor overruns;
• unanticipated site conditions;
• scope disputes;
• schedule delays;
• weak change-order recovery; and
• additional closeout costs.

Profit fade matters because early profits recognized under an optimistic estimate may need to be reduced as the estimate changes. A company with repeated fade across multiple jobs may have a larger estimating, project-management, or forecasting problem.

Profit gain is the opposite. Expected margin improves because the team performs more efficiently, procurement savings are realized, risk allowances are no longer needed, or other supported changes improve the forecast.

Profit gain is welcome, but large unexplained gains should still be reviewed. A sudden margin increase near a reporting date can deserve as much investigation as a large loss, particularly when there is weak evidence supporting the change.

A Hypothetical Multi-Job WIP Schedule

Consider this simplified construction WIP schedule:

Job	Contract Amount	Estimated Cost	Cost to Date	% Complete	Earned Revenue	Billings	Over/(Under) Billing	Estimated Profit
Alpha	$1,000,000	$800,000	$500,000	62.5%	$625,000	$700,000	$75,000 over	$200,000
Bravo	$1,500,000	$1,350,000	$810,000	60.0%	$900,000	$780,000	$120,000 under	$150,000
Charlie	$750,000	$760,000	$570,000	75.0%	$562,500	$610,000	$47,500 over	$(10,000)

These figures are hypothetical and use simplified cost-to-cost calculations for illustration.

Job Alpha appears to have a 20% projected gross margin. It is 62.5% complete by cost and $75,000 overbilled. Nothing in those facts is automatically troubling. Management should confirm that the $300,000 remaining-cost forecast is realistic and that the billing position is allowed by the contract.

Job Bravo is 60% complete by cost but $120,000 underbilled. That gap deserves an explanation. Perhaps a customer billing milestone falls later than performance, but it could also reflect delayed invoicing, pending change-order work, a billing dispute, or unsupported earned revenue.

Job Charlie requires the closest attention because total estimated cost exceeds the contract value. The project is expected to lose $10,000 even though it is overbilled by $47,500.

That example demonstrates a crucial WIP lesson: billing position does not determine profitability.

Charlie has billed ahead of earned revenue, yet the project is losing money. Bravo is underbilled but is still projected to make $150,000. Alpha is both profitable and overbilled.

If Charlie originally carried an estimated cost of $650,000, the current $760,000 forecast would also represent substantial profit fade. Management should understand when the forecast changed and whether the expected loss has been accounted for appropriately under the company’s applicable reporting framework.

Good WIP management therefore evaluates several dimensions simultaneously:

1. projected final profitability;
2. margin changes over time;
3. billing position;
4. remaining costs;
5. change-order support;
6. retainage;
7. cash requirements; and
8. project execution risk.

The underlying estimate matters from the beginning of the project. Common Estimating Mistakes Contractors Make provides additional context on using consistent cost codes and historical job data to improve estimating discipline.

How to Read a Construction WIP Schedule Step by Step

A useful WIP review does not start by looking for the biggest overbilling. It starts by establishing whether the information that drives the calculations is reliable.

1. Review Contract Values and Approved Changes

Compare each contract amount with executed agreements and the approved change-order log.

Investigate unusually large revisions. Determine whether changes are signed, whether associated costs have been included, and whether any amount is contingent, disputed, or otherwise uncertain.

This prevents a common mistake: increasing expected revenue while leaving the cost forecast unchanged.

2. Compare Estimated Costs With Actual Costs

Review the original budget, revised budget, actual cost to date, committed costs, and latest forecast.

Do not review only the job total. Look at major cost codes such as labor, materials, equipment, subcontractors, and other relevant categories.

A job that is $20,000 favorable overall may contain a $70,000 labor overrun temporarily concealed by material purchases that have not yet occurred.

Consistent construction job costing is essential. Construction management and job-cost systems commonly distinguish budgets, commitments, actual costs, and forecasted cost to complete because invoices alone do not show all known exposure.

3. Challenge the Cost-to-Complete Forecast

Ask what work remains rather than assuming the original budget remains valid.

Look for purchase orders, executed subcontract commitments, proposed subcontract changes, expected labor hours, material quantities, equipment duration, supervision, testing, punch-list work, and closeout obligations.

Committed costs are especially important. A project can appear comfortably under budget because the subcontractor has not invoiced yet even though the contractor already has an enforceable commitment.

4. Recalculate Percentage Complete

For a simplified cost-to-cost WIP, divide eligible cost incurred to date by current estimated total cost.

Then ask whether the answer makes operational sense.

If the report says the project is 85% complete but the superintendent believes only two-thirds of the work has been performed, investigate before accepting either view. The difference may arise from early material purchases, miscoding, estimate errors, or a legitimate difference between cost progress and physical progress.

5. Review Earned Revenue and Projected Margin

Confirm that the calculation follows the company’s financial reporting policies and is applied consistently.

Then compare current projected profit with the original estimate and prior reporting periods. Significant movement deserves an explanation.

The goal is not to punish project managers for forecast changes. Accurate bad news is far more useful than inaccurate good news.

6. Compare Earned Revenue With Billings

Calculate or review the overbilling and underbilling position.

Ask why the difference exists and whether it is consistent with contract terms and project circumstances.

For overbilled jobs, determine whether remaining cash and expected collections are sufficient to support remaining work. For underbilled jobs, determine what prevents billing and when the amount can reasonably convert to a receivable and cash.

7. Review Retainage Separately

Identify retainage withheld by customers and retainage withheld from subcontractors.

Check aging, expected release dates, disputed balances, project closeout status, and collectibility concerns. Retainage that has remained unpaid long after completion deserves direct follow-up rather than passive rollover.

8. Identify Profit Fade and Loss Jobs

Sort the report by margin deterioration.

A relatively small job with severe fade can reveal a control weakness more clearly than a large profitable project. Determine whether management recognized the deterioration promptly and incorporated all known remaining costs.

9. Review Backlog

Contract backlog generally represents remaining contracted work that has not yet been recognized as revenue or performed, depending on how management defines its internal measure.

Use a consistent definition. Remove canceled work and avoid counting unsupported possibilities as firm backlog.

Backlog is useful only when management understands its quality, expected timing, margin, customer concentration, and resource requirements.

10. Reconcile the WIP With the Financial Statements

The WIP should not exist in isolation.

Accounting should reconcile relevant WIP balances to the general ledger, including recognized contract revenue, job costs, billings, contract assets or liabilities as applicable, accounts receivable, retainage classifications, and other related balances.

Unexplained differences can indicate posting errors, cutoff problems, jobs omitted from the schedule, or inconsistent accounting treatment.

What Bankers, Sureties, and Financial Statement Users May Notice

No universal lender or surety checklist applies to every contractor. Credit decisions depend on the institution, facility, collateral, borrower, project mix, financial history, bond program, and many other factors.

Still, experienced financial users often look for patterns that reveal whether a contractor’s reported profitability is supported by its projects.

What Bankers May Look for in a WIP Report

A banker may consider:

• consistency of gross margins;
• large profit fade;
• significant loss jobs;
• unusually high underbillings;
• unusually high or rapidly increasing overbillings;
• retainage and receivable aging;
• cash and working-capital trends;
• customer or project concentration;
• backlog quality;
• debt obligations;
• estimate reliability; and
• whether WIP information agrees with financial statements.

The lender may also compare construction cash flow with reported earnings. If net income looks strong while operating cash remains consistently weak, receivables, retainage, underbilling, inventory, equipment purchases, debt service, or other factors may explain the difference.

SBA lending materials illustrate the broader principle that lenders consider repayment ability and financial information rather than relying solely on headline profit. SBA’s 7(a) program permits qualifying uses that include working capital, while actual underwriting and required documents depend on the lender and transaction.

What Bonding Companies and Sureties May Review

Sureties assess whether a contractor appears financially and operationally capable of performing bonded work. Financial information is only part of that evaluation.

Depending on the situation, a surety may examine:

• current and projected backlog;
• job profitability;
• historical project performance;
• working capital;
• net worth;
• cash resources;
• job concentration;
• contract size relative to experience;
• management depth;
• financial-report quality;
• profit fade;
• loss jobs; and
• reliability of WIP forecasting.

A bonding company WIP report that contains persistent optimistic estimates followed by late project losses may create questions even if the company’s current totals look acceptable.

Conversely, a contractor that updates estimates promptly and can explain negative changes with documentation may demonstrate stronger financial control.

No single WIP ratio should be presented as a universal surety standard, and contractors should avoid relying on unsupported “ideal” percentages.

Spotting Overbilling Before Your Banker Does

Overbilling becomes more informative when combined with other signals.

Before submitting financial information, review for:

• unusually high overbilling compared with remaining work;
• overbilling paired with shrinking projected margins;
• large customer advances while company cash declines;
• remaining contract value that appears insufficient to fund projected remaining costs;
• unexplained reductions in estimated cost to complete;
• missing commitments or subcontractor exposure;
• heavy use of cash generated by one project to support unrelated jobs;
• sudden estimate changes near financial reporting dates;
• significant pending changes treated as though fully recoverable;
• overbilled loss jobs; and
• large retainage balances with uncertain collection timing.

None of these observations alone proves wrongdoing.

For example, a contractor may intentionally bill mobilization early under explicit contract terms and use centralized company cash management. The issue is whether the WIP, cash forecast, and remaining obligations support the position.

How WIP Connects to the Balance Sheet, Income Statement, Cash Flow, and General Ledger

Construction accounting WIP becomes much easier to understand when you stop treating the schedule as a stand-alone report and trace its numbers into the financial statements.

WIP and the Balance Sheet

Under ASC 606, the relationship between performance and customer payment may result in a contract asset or contract liability on the balance sheet.

Broadly, a contract asset represents a right to consideration for goods or services transferred to the customer when that right is conditional on something other than merely the passage of time. A receivable is an unconditional right to consideration.

A contract liability generally reflects an obligation to transfer goods or services for which consideration has been received or is due from the customer.

FASB’s construction-focused educational material emphasizes contract-by-contract net presentation under Topic 606 and also notes that retainage classification depends on whether the contractor’s right to payment is unconditional.

Older construction terminology such as costs in excess of billings and billings in excess of costs remains common in conversation and legacy reports. For GAAP financial statements, however, contractors and their CPAs should use terminology and classification consistent with the applicable reporting framework rather than assuming old labels map perfectly to ASC 606.

WIP and the Income Statement

The WIP schedule helps support the amount of revenue and gross profit recognized for active contracts under the company’s applicable accounting policies.

When estimated project economics change, the recognized results can change.

Consider the earlier $1 million project. If expected total cost rises substantially because management forecasts additional labor and subcontractor expense, the calculated stage of completion and projected profit may decline. The resulting WIP adjustment can therefore affect current-period revenue and gross profit.

This is why a small change to a spreadsheet forecast can have a material effect on construction financial statements.

Job-level estimate revisions should have operational support, not simply a desired income-statement outcome.

WIP vs. Cash Flow

The most important distinction is:

Profit is not cash, billings are not necessarily earned revenue, and retainage is not immediately available cash.

A contractor can report profitable earned revenue while waiting weeks or months for customer payment.

A project can also be substantially underbilled, requiring the contractor to pay payroll, suppliers, equipment, and subcontractors before generating a corresponding receivable.

Conversely, an overbilled project can generate strong current cash even though much of that cash is economically needed for future performance.

Consider an overbilled job that has collected $700,000 but has $300,000 of expected cost remaining. Management cannot evaluate available liquidity by looking at the bank account alone. It needs a companywide cash forecast incorporating remaining project spending, payroll, taxes, debt, overhead, receivables, and retainage.

WIP and Accounts Receivable

Accounts receivable should be reviewed beside WIP, not as a substitute for it.

Important categories include:

• billed trade receivables;
• retainage amounts;
• disputed invoices;
• aged customer balances;
• credits or offsets;
• amounts pending contractual documentation; and
• collection timing.

A contractor can be properly billed according to the WIP and still experience serious cash stress if customers pay slowly.

Likewise, aggressive invoicing provides little liquidity if amounts are routinely disputed or uncollectible.

WIP and Backlog

Backlog connects today’s WIP with tomorrow’s workload.

Management should define backlog consistently and distinguish signed contractual work from proposals, verbal expectations, tentative awards, or unsupported changes.

A large backlog is not automatically positive. Contractors must consider its expected margin, schedule, labor requirements, equipment requirements, concentration, bonding needs, and working-capital demands.

A low-margin $20 million backlog can carry more risk than a carefully selected $10 million backlog with stronger margins and manageable scheduling.

Building a Reliable Monthly WIP Review Process

The strongest construction accounting controls do not depend on one accountant fixing the WIP at quarter-end. They create a repeatable monthly process in which project management, operations, estimating, and accounting contribute different information.

Monthly review is common for many contractors because it aligns reasonably well with financial closing and project-management cycles. Some companies need more frequent updates because of project size, complexity, lender requirements, rapid cost movement, or internal reporting needs.

Job Cost Reporting and Committed Costs

A reliable WIP starts with reliable job costs.

Cost codes should be detailed enough to show meaningful variances without becoming so complicated that field and accounting employees cannot use them consistently.

Relevant categories may include:

• field labor;
• payroll burden where appropriate;
• materials;
• subcontractors;
• equipment;
• rentals;
• permits;
• project supervision;
• other direct project costs; and
• overhead allocations when appropriate under company policy and the applicable accounting framework.

Bad coding creates bad WIP.

If framing labor gets coded to concrete, or a subcontractor change is posted to the wrong job, the total company expense might still be correct while individual job forecasts become unreliable.

Committed costs should supplement recorded actual costs. Purchase orders, executed subcontracts, approved subcontract changes, and other commitments tell management about obligations that may not yet appear as invoices.

Monthly WIP Review Workflow

A practical process can look like this:

1. Update job costs: Post available labor, materials, subcontract invoices, equipment, and other project costs through the reporting cutoff.
2. Review commitments: Identify purchase orders, subcontracts, pending vendor bills, and known cost exposure not yet recorded.
3. Update change orders: Separate approved, pending, disputed, and rejected changes. Update associated cost forecasts.
4. Forecast remaining labor: Estimate hours, crews, production rates, overtime, and supervision required to finish.
5. Forecast remaining subcontractor and material cost: Include known scope gaps, likely extras, and procurement exposure.
6. Review billing status: Determine whether progress invoices match contractual billing rights and project administration.
7. Review retainage: Confirm customer and subcontractor retainage, expected release timing, and collection issues.
8. Document project risks: Capture delays, claims, rework, customer disputes, labor problems, or other conditions affecting financial outcome.
9. Update estimated total cost and margin: Use current information rather than carrying the prior month’s estimate forward automatically.
10. Reconcile the WIP: Accounting should tie the completed report to relevant general-ledger and financial-statement balances.

WIP Review Questions for Project Managers

A productive WIP meeting should require more than “yes” or “no.”

Ask:

• What physical work remains?
• Which costs have been incurred but have not reached accounting?
• What purchase orders remain open?
• Are subcontractors projecting extras or overruns?
• Has labor productivity changed?
• How many labor hours remain by major phase?
• Are material prices or quantities changing?
• Which change orders are approved?
• Which change orders remain uncertain?
• Are billing milestones current?
• Is any customer withholding payment beyond normal retainage?
• Are there claims, delays, backcharges, or disputes?
• What testing, punch-list, warranty, and closeout costs remain?
• Has the expected finish date changed?
• What could make the current profit forecast wrong?

These questions make the WIP forward-looking.

A report based solely on invoices tells management what happened. A strong construction work in progress report tells management what has happened and what it currently expects will happen next.

Common WIP Accounting Mistakes and a Practical Review Checklist

Many inaccurate WIP schedules result from ordinary process weaknesses rather than complicated accounting issues.

One of the most common errors is a stale estimated total cost. If the project manager updates remaining costs only when a problem becomes impossible to ignore, reported margin can stay too high for months and then collapse near project completion.

Another problem is missing invoices. A subcontractor may have performed $100,000 of work that is absent from the job-cost report because its invoice has not arrived. Unless management captures the commitment or accrual appropriately, the job may appear more profitable than it is.

Other common mistakes include:

• treating unapproved change orders as though collection were certain;
• failing to include related change-order costs;
• using an inaccurate percent complete;
• ignoring retainage;
• double-counting costs;
• omitting committed costs;
• inconsistent job-cost coding;
• failing to reconcile WIP with the general ledger;
• delaying recognition of known project deterioration;
• automatically treating billings as revenue;
• leaving completed jobs on WIP indefinitely;
• carrying uncollectible or disputed amounts without evaluation; and
• failing to update expected closeout costs.

A disciplined review checklist can catch many of these problems.

Review Area	Question to Ask
Contract value	Is the amount supported by executed documents?
Change orders	Which changes are approved, pending, disputed, or rejected?
Cost to date	Are all significant incurred costs recorded or otherwise considered?
Cost to complete	Is the forecast based on current remaining work?
Percent complete	Does the measure follow policy and make sense given project facts?
Earned revenue	Is it calculated consistently under the applicable method?
Billings	Are contractual billing milestones current?
Retainage	Is it properly tracked, classified, aged, and collectible?
Overbilling	Why are billings ahead, and how much cash is required to finish?
Underbilling	Why has earned performance not converted to billing?
Margin	Is there profit fade or unexplained profit gain?
Backlog	Is the remaining work supported and economically realistic?

WIP Metrics Worth Monitoring

Useful management metrics include estimated gross margin, margin fade or gain, overbilling, underbilling, retainage aging, backlog, job concentration, projected remaining cash requirement, and forecast accuracy.

Avoid imposing a universal benchmark without context.

A 10% overbilling may be normal on one contract and impossible under another. A large retainage balance may reflect normal project terms or severe closeout problems. A lower gross margin may be acceptable for a strategically important repeat client but dangerous on a high-risk one-off project.

Trend analysis is usually more informative than a generic industry percentage.

Compare:

• current margin with original margin;
• current margin with prior-month margin;
• projected final cost with original budget;
• WIP forecasts with actual completed-job results;
• underbilling trends over several periods;
• retainage aging by project and customer; and
• backlog growth with available labor and working capital.

How Often Should WIP Be Updated?

For many contractors, a formal monthly WIP update is a reasonable operational rhythm because it matches month-end accounting and management reporting.

However, frequency should reflect company size, job duration, project volatility, lender or surety reporting obligations, and management needs.

A contractor performing short, fast-moving projects may need weekly forecasting for important jobs. A company with longer and more predictable work may rely on monthly formal reporting supplemented by project-level cost reviews.

The key is consistency. Updating WIP only when a lender, CPA, or surety asks for it limits its value as a management control.

WIP and Year-End Financial Statements

Year-end WIP deserves careful review because estimates may materially affect annual reported revenue, gross profit, contract assets, contract liabilities, and other financial-statement information.

But year-end should not be the only time estimates receive serious attention.

A contractor that “cleans up” WIP once a year is likely managing with stale information for the other eleven months. Monthly discipline makes year-end reporting less disruptive and gives management more time to respond to deteriorating jobs.

Significant estimate changes should be supported by actual project information, not by a desired annual profit number.

WIP and Tax Reporting Are Not the Same Thing

Financial-statement construction WIP, management job-cost reporting, and federal income-tax accounting can use related information while following different rules.

For U.S. federal tax purposes, Internal Revenue Code Section 460 generally contains percentage-of-completion rules for many long-term contracts, along with statutory and regulatory exceptions and specialized provisions. 

IRS materials describe a cost-based completion factor for contracts subject to the percentage-of-completion method, but eligibility for exceptions and other tax treatment depends on the taxpayer and contract.

Tax rules also change, and different contract types can receive different treatment. Contractors should therefore avoid taking an internal WIP calculation and assuming it automatically equals taxable income.

The company’s CPA or tax adviser should address questions such as:

• Which long-term-contract tax rules apply?
• Does a statutory exception apply?
• How are contract costs determined for tax purposes?
• Are special look-back rules relevant?
• How do tax methods differ from book reporting?
• How should retainage and change-order amounts be treated for the specific taxpayer?

The distinction is important because a contractor can have one set of operational job-cost reports, ASC 606 financial statements prepared under U.S. GAAP, and a tax return reflecting separate statutory rules.

Those systems should reconcile where appropriate, but they are not interchangeable.

Before relying on WIP for outside reporting, contractors should ask their CPA or controller:

• Which revenue-recognition method are we applying?
• How do we determine and document our measure of progress?
• How are retainage balances classified?
• How are overbilling and underbilling reflected in our financial statements?
• How do we account for pending and disputed change orders?
• How frequently should estimated costs be updated?
• How do we account for expected loss jobs?
• Does the WIP reconcile to the general ledger?
• Which costs are included in our cost-to-cost calculation?
• What information will our lender or surety receive?
• Are our internal WIP labels consistent with financial-statement terminology?
• How does our tax accounting differ from our book accounting?

Frequently Asked Questions

Conclusion

Retainage and WIP schedules are not simply reports prepared for an accountant, banker, or bonding company. They are among the most useful financial-management tools a contractor can maintain.

A strong construction WIP schedule connects contract value, estimated total cost, actual cost, estimated cost to complete, percentage complete, earned revenue, billings, retainage, projected profit, and backlog. Those relationships reveal risks that an income statement alone cannot show.

The key is to interpret the numbers together.

Overbilling may provide healthy working capital when it reflects legitimate contract terms, but cash received today may still be needed for tomorrow’s work. 

Underbilling may reflect ordinary timing, or it may indicate weak billing controls, unresolved changes, inaccurate estimates, or project problems. Retainage may represent valid economic value while remaining unavailable for immediate cash needs.

Most importantly, the cost-to-complete estimate must remain realistic. A contractor cannot manage construction job profitability effectively when the forecast ignores known labor overruns, outstanding commitments, subcontractor exposure, change-order risk, or closeout costs.

Review WIP consistently, reconcile it to the accounting records, document estimate changes, and involve the people closest to each project. 

If management can explain why every major job’s contract value, remaining cost, margin, billing position, and retainage balance make sense, the company is far less likely to discover a financial surprise only after a lender, CPA, or surety asks about it.

This article is provided for general educational purposes and does not constitute individualized accounting, tax, lending, bonding, financial, or legal advice. 

Construction accounting and tax treatment can vary based on contract terms, accounting method, financial reporting framework, tax elections, company policies, jurisdiction, and specific facts. Contractors should consult qualified accounting, tax, legal, banking, and surety professionals regarding their circumstances.