By Noa Benitez, founder of BenIT, an AI consultancy in Toulouse.
Your progress invoice is the only document that turns your job site's progress into payment. Miscalculated, it makes you front your own cash for two months on average. Calculated correctly, it finances the job as it moves forward.
The problem isn't legal. French building law has covered progress invoices for a long time. The problem is practical: no one explains how to measure real progress on site, lot by lot, and turn it into a billable line without getting a single point wrong. This article gives the complete method, from the site survey to the signature, including down payment calculations and progress tracking.
What is a progress invoice, and why does it block your cash flow?
A progress invoice is an interim invoice issued during the execution of a job, as opposed to the final invoice, which comes at handover. It covers work actually carried out over a given period, usually monthly. Its legal basis is set out in Articles 1792-6 and R243-1 of the French Insurance Code and Building Code.
The bottleneck comes from the timing gap. You pay your suppliers in 30 days, your employees on the 15th of the month, your equipment cash up front. Meanwhile, the project owner only pays once your progress invoice is received, then within 30 or 60 days. The gap between what goes out and what comes in widens with every poorly filled-in line or every underestimated progress percentage.
Source: order-of-magnitude figures from BenIT's tracking of construction SMBs with 20 to 80 employees
Six hours a week. That's how much time a construction business owner spends on average on job site reporting, based on what we observe with our clients before rollout. Progress surveys, entering data into the software, checking quantities, formatting the progress invoice, sending it, following up. Half of that time is re-entering data between the field and the invoicing tool.
To see the detail of those six lost hours and what they mean over a work week. A typical day for a construction business owner: 6 hours lost
How do you calculate real progress on site?
This is the step that makes the difference between a progress invoice that finances the job and one that leaves you out of pocket. The percentage of progress can't be guessed from the office. It has to be measured on site, lot by lot, and checked against the contract.
The method in five points:
How much every statement error costs you
Thirty minutes to run the numbers on your actual job site figures, no strings attached.
Message us on WhatsApp- Physically survey the quantities completed for each lot in the CCTP (special technical specifications): linear meters of pipe laid, square meters of slab poured, tons of rebar placed. No visual estimates.
- Compare each quantity to the total specified in the bill of quantities to get a progress rate per lot. Example: 400 linear meters laid out of 1,000 planned gives 40% progress on that lot.
- Weight each lot by its financial share of the total contract. A €15,000 plumbing lot that's 10% complete carries less weight than an €80,000 structural lot that's 5% complete.
- Apply the 5% retention on the cumulative amount invoiced to date, as required under the CCAG travaux (standard terms for public works contracts).
- Deduct previous progress invoices so you only bill for the current period's work, never the same quantity twice.
The most common mistake is billing in proportion to time elapsed rather than actual quantities completed. A three-month job where two months have gone by doesn't mean 66% of the work is done. If the structural work is behind schedule and the finishing trades haven't started, the billable percentage is often much lower.
Calculating the amount of a progress invoice
Progress invoice amount = (Σ quantity completed per lot × unit price per lot) × (1 − retention) − cumulative amount of previous progress invoices
Masonry lot: 400 m² poured out of 1,000 m² × €65/m² = €26,000. Plumbing lot: 200 linear meters laid out of 800 linear meters × €40/lm = €8,000. Total for the period: €34,000. 5% retention: €32,300. Previous progress invoice: €18,000. Amount of this progress invoice: €14,300.
Run the calculation with your own numbers.
The 7 steps to draw up your progress invoice without errors
A construction progress invoice follows a precise process, from the field to payment. Here are the seven steps in order.
- Site survey by the site supervisor or project manager: quantities completed per lot, dated photos, any extra work observed.
- Cross-check between the site survey and the contract's bill of quantities: every completed quantity must match a line in the contract or a signed amendment.
- Calculate the progress percentage per lot using the weighted method described above, including the retention and the deduction of previous progress invoices.
- Draw up the statement on Cerfa form n° 12265*05 or the template required by the project owner, broken down lot by lot.
- Format the invoice with the required details: progress invoice number, period covered, contract reference, amount excl. VAT, applicable VAT rate, retention, cumulative amount of previous progress invoices, net amount due.
- Send it to the project owner within the deadline set by the contract, usually within eight days of the end of the period, along with the supporting documents requested.
- Track the signature and the payment: follow up at day 15 if it's still unsigned, follow up at day 30 if it's still unpaid, per the contract's deadlines.
To understand what your management software handles and what's still manual. Construction progress tracking: what your software does and what's left
Which tool for tracking: Excel, industry software, or a dashboard?
Get your Monday mornings back on the job site
Thirty minutes to see what BenIT can automate on your progress invoices, no strings attached.
Block off thirty minutesThree approaches dominate among construction SMBs. None is perfect. Here's what each one actually covers.
What each tool covers for progress tracking
| Criterion | Excel or Google Sheets | Construction industry software | Automated dashboard |
|---|---|---|---|
| Site survey | Manual | Partial | With on-site data entry |
| Weighted progress calculation | Manual formula | Depends on the software | Automatic per lot |
| Cerfa formatting | Manual | Automatic | Automatic |
| Follow-up tracking | Manual | Partial | Automatic |
| Weekly time spent | 5 to 8 hours | 3 to 5 hours | 1 to 2 hours |
| Risk of statement errors | High | Medium | Low |
Excel remains the most widely used tool. It's flexible, free, and requires no training. It also demands constant discipline around formulas, updates, and backups. One copy-paste error on a progress percentage and the whole progress invoice is off.
Industry software such as Batigest, EBP Bâtiment, or Onefacture automates formatting and storage. It doesn't go out to the site to measure completed quantities. It doesn't check that the declared progress percentage matches the reality on the ground. The survey stays manual, and so does the data entry.
An automated dashboard connects the site survey to the progress calculation and the progress invoice generation. That's what BenIT deploys for its construction clients: the site supervisor enters quantities from the field, the calculation runs itself, the progress invoice is generated with the right weighting, follow-ups trigger at the right deadlines. Reporting time drops from six hours to an hour and a half a week.
What the software doesn't do for you
Your management software produces the invoice. It doesn't check that the declared progress percentage matches the quantities actually completed on site. That check remains your responsibility, and that's where the financial risk lies.
The 3 traps that derail the statement and the payment
Forty percent of payment delays stem from a statement error on the progress invoice, according to data from the Payment Deadlines Observatory published by the Banque de France. Here are the three costliest traps.
- Forgetting to deduct previous progress invoices. You end up re-billing work that's already been paid for. The project owner spots it, blocks payment, and you lose thirty to sixty days. Every progress invoice must carry forward the cumulative total of prior progress invoices as a deduction.
- Including work not covered by the contract without a signed amendment. Extra work carried out on a verbal instruction doesn't belong on the progress invoice until a formal amendment has been drawn up. Billing it without one means risking never getting paid at all.
- Misapplying the retention. The 5% retention applies to the total amount invoiced to date, not the net amount. Applying it after deducting previous progress invoices instead of before creates a discrepancy that blocks approval.
A free audit of your most time-consuming process
Thirty minutes to run the numbers on your actual figures, no strings attached.
Book the free auditThe most underrated trap is the submission deadline. Most contracts require sending within eight days of the end of the period. Miss that window and the project owner can reject the progress invoice or push it to the next period. A month of cash flow gone because a deadline was missed.
When manual tracking costs more than delegating
The math is simple. Six hours a week of reporting adds up to 312 hours a year. At a construction business owner's hourly value, between €80 and €120, that's between €25,000 and €37,500 a year, based on Capeb data on tradesperson-owner pay. Add the cost of statement errors, payment delays, and the two months of cash flow fronted on average.
Delegating progress tracking doesn't mean losing control. The site supervisor still surveys quantities on the ground. The owner still signs off on the progress invoice before it's sent. What changes is that the calculation, the formatting, the cross-check against the bill of quantities, and the follow-ups no longer rest on their shoulders.
To see how BenIT rolls out an AI collaborator for tracking your progress invoices. The method in 4 steps
What BenIT actually automates on the construction progress invoice: on-site progress surveys, weighted calculation per lot, deduction of previous progress invoices, applying the retention, Cerfa formatting, sending it to the project owner, and follow-ups at day 15 and day 30. The owner keeps control over validation before signature.
To see the subscription tiers and what each level of monthly tracking covers. Delegate progress tracking