Construction margins are under pressure from every direction. Material prices remain volatile, labour availability is tight, and programmes are being delivered against increasingly compressed timelines. In that environment, cost control depends on understanding how money moves through a project while work is still underway.

One category of spend consistently escapes that scrutiny: out-of-pocket expenses. Fuel, mileage, accommodation, subsistence and small equipment purchases are routine in construction. Capture Expense data shows these costs are being covered upfront by workers at scale. In 2025, construction workers submitted 22,556 expense claims through the platform, reclaiming £1.5 million they had already paid themselves. They average claim value was £66.19, indicating frequent, low-value transactions rather than exceptional purchases.

These costs are operationally necessary, but they rarely sit within formal procurement or cost-planning processes. As a result, they often reach finance teams late and with limited context.

Paper-based capture slows cost recognition

Our data shows that construction expense capture remains heavily paper-led. In 2025, construction workers submitted 11,503 paper receipts, compared with 3,977 digital receipts. Physical receipts accounted for almost three quarters of all receipt submissions across the sector.

Paper receipts are typically submitted after the event, often in batches. When claims reach review, the spend may be days or weeks old. The transaction is visible, but the circumstances around it are not. Approval data further reflects this delay. While the median time to full approval is 1.8 days, the average approval time stretches to 8.2 days, indicating that a large proportion of claims sit in the systems for more than a working week.

During that period, costs remain absent from living project reporting. Forecasts rely on partial information and expense cost adjustments often arrive after commercial decisions have already been made. This timing gap affects how projects look while they are underway. Expense spend does not surface gradually alongside delivery. It appears later, often in clusters, once claims near approval.

For construction businesses operating across multiple sites, that lag reduces the usefulness of expense data during active projects and shifts cost control into retrospective explanation rather than real-time management.

What expense claims show about pressure on site

Expense claims capture how projects behave when timelines tighten. Our data from 2025 shows that the most common construction expense categories are mileage and transportation, subsistence, hotel and overnight stays, and equipment and hardware. These claims track activity during delivery rather than planning and tend to increase when programmes compress or resourcing stretches.

Mileage claims reflect movement between sites and changes to site allocation. Subsistence claims rise with extended shifts. Overnight stays increase where work overruns or travel becomes unavoidable. Equipment purchases submitted through expenses point to gaps between what was planned and what was needed in practice.

The same conditions that generate these claims also explain why they later become difficult to process. Claims created during live work are rarely submitted immediately. The data shows that construction expenses are frequently submitted with paper receipts and reach approval days after the spend occurred. By the time claims enter review, operational detail has often been lost.

This shows up clearly in rejection data. Hotel and overnight stays claims have a 9.8% rejection rate, while subsistence claims are rejected 6% of the time. Mileage claims account for the highest volume of rejections, despite a comparatively low rejection rate of 1.87%. The primary causes behind the rejections are consistent too: vague descriptions, missing information, and unclear audit trails.

The result? A feedback loop. Site pressure generates expense activity. Delayed capture weakens data quality and weaker data increases handling time. Cost visibility moves further away from the point of decision-making.

The impact on margins

Construction margins rarely fail because of a single cost overrun. They erode through accumulated, tolerated spend that sits outside formal controls. Expenses sit squarely in that category.

Our data shows a steady flow of low-value, high-frequency claims moving through construction firms every week. When visibility is delayed, commercial teams manage projects using partial information. Corrections arrive late, often in clusters, rather than informing decisions as work progresses. Expense visibility does not eliminate these costs, rather, it determines whether they are understood early or explained later.

Expense management reflects how construction work actually gets done. The data shows workers regularly bridging gaps between planning and delivery with their own money. Those transactions carry useful information about pressure points on site, but only if they are captured and reviewed in time.

In an industry where margins are tight and programmes are unforgiving, delayed cost visibility creates avoidable risk. Expense data will always exist, but the question is whether it informs delivery or simply documents it after the fact.