Retainage is usually introduced as a small percentage. That is mathematically true and operationally misleading.
At the end of 2025, three public specialty contractors reported a combined $2.67 billion in amounts retained by their customers. Quanta Services reported $994.1 million expected to settle within a year and another $228.7 million expected beyond one year. EMCOR reported $944.5 million. Comfort Systems USA reported $506.5 million.
I chose these three for a narrow reason. Each is a large public specialty contractor whose 2025 Form 10-K separately identifies customer retainage. They are not a representative sample of trade contractors, and the total is not an estimate for the industry. It is simply a visible subset that lets us inspect a contract mechanism that is usually discussed as a rate instead of as a balance.
The more interesting disclosure is one level down.
What was held from them, and what they held from others
EMCOR reported $944.5 million of billed retainage withheld by customers and $152.3 million of retainage it withheld under its subcontracts. Comfort Systems reported $506.5 million in customer retention balances and $83.1 million in subcontractor retainage.
At EMCOR, the first number was 6.20 times the second. At Comfort Systems, it was 6.10 times. Together, those two companies had $1.451 billion retained by customers and $235.4 million retained from their subcontractors, a difference of about $1.216 billion.
That comparison needs a fence around it. The disclosures do not tell us whether the customer and subcontract balances cover identical projects, contract terms, completion stages, or scopes. Quanta does not disclose an equivalent subcontractor-retainage balance in the cited section, so I excluded it from the ratio. These figures also do not show when each dollar was earned or its financing cost.
What they do show is simpler: at these two companies, disclosed customer retainage receivable exceeded disclosed retainage payable to subcontractors by $792.2 million and $423.4 million, respectively. Downstream withholding did not offset the customer-side balance dollar for dollar at the consolidated balance-sheet date. That is an absolute-balance observation, not a claim that the firms used different retainage rates or failed to pass through a contract term.
The word small is doing too much work
Quanta says certain contracts allow customers to withhold a small percentage of billings. Comfort Systems describes a small portion of progress billings or contract price, typically held for six months after the work is complete. Both descriptions are reasonable. Neither percentage nor duration can describe the burden alone.
A stated retainage hold on one payment is a rate. The same rate held across a growing book of work, with different completion dates and release conditions, becomes a portfolio of receivables. The balance turns on at least four variables:
the retainage rate, the amount of work subject to it, the point when the right to payment becomes unconditional, and the time between that point and collection.
Only the first one fits neatly in the phrase small percentage.
The year-over-year movement makes the distinction visible. Across the same three filings, reported customer retainage rose from $1.843 billion at the end of 2024 to $2.674 billion at the end of 2025, an increase of about 45 percent. That does not prove retainage terms became worse. Quanta and the other firms grew, acquisitions affected their operations, project mix changed, and the filings do not isolate rate from volume or duration. The honest conclusion is not that customers suddenly tightened the screws. It is that the balance grew much faster than the phrase small percentage would prepare a reader to expect.
The release trigger matters as much as the rate
Comfort Systems says customer retention is typically held until after it has completed work, usually for about six months, and that most year-end balances are finalized and collected in the following year. EMCOR estimated that about 90 percent of its year-end customer retainage would be collected during 2026. Quanta separated $228.7 million whose expected settlement date was more than one year away.
Those are three different ways of showing the same practical issue. A retained dollar can sit behind physical completion, contractual completion, acceptance, final documentation, or another event defined by the contract. A trade can be finished in the field and still be early in the payment sequence.
That is why I think the rate is the wrong place to end a contract review. A subcontractor deciding whether the stated rate is acceptable still does not know enough. The useful questions are tied to artifacts and handoffs:
Does retainage reduce when the trade's scope is substantially complete, or only when the whole project reaches a later milestone? Which closeout documents must be accepted before release? Can a disputed punch-list item hold the entire retained balance or only a stated amount? Does the payment application show earned retainage separately from amounts that have become billable? Who owns the release package, and on what date does that person start it?
Those are not accounting questions after the job. They are bid and operations questions before the job.
The federal rule shows that routine withholding is a choice
Private contracting is not governed by the federal fixed-price construction clause, but that clause is a useful contrast. FAR 52.232-5 says the contracting officer shall authorize full progress payment when satisfactory progress has been achieved. If satisfactory progress has not been made, the officer may retain up to 10 percent until it is. At substantial completion, the officer may keep an amount considered adequate to protect the government and release the remainder. FAR 32.103 adds that retainage should not substitute for good contract management, funds should not be withheld without cause, and each decision should be made case by case.
That structure treats withholding as a response to progress, not an automatic feature of every payment. It also requires the prime contractor's progress-payment request to list work and prior payments by subcontractor, and the prime must certify that previous payments due to subcontractors and suppliers have been made.
I am not arguing that the FAR clause should be copied into every private subcontract. Public procurement has different remedies, oversight, and risk allocation. I am pointing out that a major construction owner can protect itself without defining routine retainage as the default answer to satisfactory progress.
Backlog and retainage describe opposite ends of the job
Backlog gets the headline because it describes work that may become revenue. Retainage describes revenue already recognized or billed for work already performed, but not yet collected. One points forward. The other looks back.
A contractor can therefore have a strong backlog and a growing retained balance at the same time. Those conditions do not contradict each other. They make working-capital discipline more important because growth adds work at the front while project acceptance and closeout control cash at the back.
The place to manage that is not one aging report at year end. It is the chain from bid review to payment application to closeout:
At bid review, record the rate, reduction provision, release trigger, and any dependency on owner payment or whole-project completion. In the schedule of values and each payment application, keep earned, billed, retained, and unbilled amounts distinct. Before field completion, assign every required warranty, operation manual, as-built, test report, lien release, and punch item to an owner and a due date. In the work-in-progress meeting, review retained balances by release condition, not only by age.
None of that makes the contract fair. It makes the cash path visible soon enough to price it, negotiate it, and close it.
What these filings cannot tell us
The three companies are among the largest public firms in specialty construction. Their access to capital, customer mix, bargaining position, project scale, and internal controls are not those of a local flooring, mechanical, or electrical subcontractor. Their balances cannot be scaled down into a small-contractor estimate.
The filings also do not provide project-level retainage rates, average collection time, disputed amounts, or the financing cost of the retained cash. The combined total is a sum of reported point-in-time balances under each company's accounting presentation, not a survey measure. The comparison between customer and subcontractor retainage is available for two firms, not all three.
That limitation is part of the argument. If this much customer retainage is visible in three public filings, the right question for a subcontractor is not whether the percentage looks customary. It is how many dollars will be held, for which release condition, and for how long.
Retainage belongs in the bid decision, the project controls meeting, and the closeout plan. Calling it a closeout detail waits until the work is done to ask when the work gets paid.