What article 47 requires
The text runs to three paragraphs of the amended law of 8 April 2018 on public procurement. Paragraph 1 requires a final account for all contracts. Above EUR 20,000 excluding VAT, expressed in index value 100 of the consumer price index, this account, drawn up after acceptance of all the services, must include "a comparison with the estimate drawn up for the contract award procedure and a comparison, by trade, of the contract price and the final cost of the whole contract, additional contracts included" (unofficial translation). That index-based amount is updated; its 2026 value does not appear on the public procurement portal pages dealing with thresholds.
Paragraph 2 isolates price movements: "Where the estimate or the agreed price is exceeded, the statutory increases (hausses légales) are to be shown separately." Paragraph 3 sets the burden of proof: "A justification is to be provided for all overruns exceeding the statutory increases."
The word "estimate" (devis) has its Luxembourg meaning here. It does not refer to a contractor's bid, but to the estimate drawn up by the contracting authority (pouvoir adjudicateur) before the tender, the one used to choose the procedure and which may not be disclosed to tenderers (implementing Grand-Ducal regulation of 8 April 2018, art. 45 (5)). The final account thus closes the loop opened by that estimate.
Two variances, not one
The comparison required by law brings out two variances of a different nature. The first, between the estimate and the contract price, measures the quality of the estimate and the state of the market at the time of tendering: it is known at award. The second, between the contract price and the final cost, measures what happened during execution: additional contracts, quantity variances, statutory increases.
| Variance | What it measures | When it is known | What explains it |
|---|---|---|---|
| Estimate → contract price | the estimate against the tenders | at award | market prices, completeness of the documents, division into packages |
| Contract price → final cost | execution | as the works progress, closed in the final account | amendments and additional contracts, actual quantities, statutory increases |
| Estimate → final cost | the total variance to be justified | in the final account | sum of the two variances, statutory increases shown apart |
Confusing the two variances means choosing the wrong remedy. An overrun that arose at award cannot be corrected on site; it tells you how to estimate the next project. An overrun that arose during execution, on the other hand, was to be managed item by item, and the final account only tells you whether that management worked.
A fictitious example
The following example is entirely fictitious, with round amounts excluding VAT, and serves only to show how the table is built. A contracting authority has drawn up an estimate of EUR 1,800,000 for 3 packages.
| Trade | Estimate | Contract price | Additional contracts | Statutory increases | Final cost |
|---|---|---|---|---|---|
| Structural works | EUR 900,000 | EUR 950,000 | EUR 40,000 | EUR 25,000 | EUR 1,015,000 |
| Facades | EUR 500,000 | EUR 480,000 | EUR 10,000 | EUR 12,000 | EUR 502,000 |
| Building services | EUR 400,000 | EUR 430,000 | EUR 30,000 | EUR 8,000 | EUR 468,000 |
| Total | EUR 1,800,000 | EUR 1,860,000 | EUR 80,000 | EUR 45,000 | EUR 1,985,000 |
The reading is done in three stages. The total overrun on the estimate is EUR 185,000 (1,985,000 minus 1,800,000). Statutory increases, shown separately, account for 45,000 of it. That leaves EUR 140,000 to be justified: EUR 60,000 arising at award (1,860,000 minus 1,800,000) and EUR 80,000 of additional contracts arising during execution. The justification is written package by package: structural works alone carry EUR 50,000 of award variance and EUR 40,000 of additional contracts, which points the analysis in the right direction.
The facades package shows that a total is not enough. Awarded below the estimate, it partly offsets the other packages in the total; the comparison by trade required by law prevents that offset from masking the variances.
Justifying an overrun
The justification required by article 47 (3) is about causes, not amounts. For each package that overruns beyond the statutory increases, it links the variance to a document: the signed amendment and the article 43 case it falls under, the measurement establishing an actual quantity above the bill quantity, or the analysis of the award variance.
| Cause | Document that supports it | Where to track it during the works |
|---|---|---|
| Additional contract, amendment | signed amendment, article 43 case, council resolution if needed | approved amendments line |
| Actual quantities | joint measurement, interim valuations | quantity variances line |
| Award variance | tender analysis report, dated estimate | "contract price" column |
| Statutory increases | calculation under the clause in the special specifications | separate line, not to be justified |
Amendments (avenants) and their ceilings are described in the article on amendments to a public contract in progress. The move from bill quantities to quantities actually carried out, and how to establish them jointly, is covered in the article on the final account and actual quantities. Here, only their place in the comparison matters.
The State and municipal procedures
For the State, major works go all the way up to the Chamber of Deputies. Article 48 of the 2018 law covers works whose cost exceeds the amount set in article 80 of the amended law of 8 June 1999 on the State's budget, accounts and treasury, namely EUR 60,000,000, corresponding to value 1,037.72 of the annual construction price index. Their final account is sent to the Minister for the Budget and to the Chamber of Deputies within one year of acceptance, with justification of overruns exceeding the statutory increases, and is subject to review by the Court of Auditors (Cour des comptes).
For a municipality, the final account goes back to the municipal council. Article 148 of the implementing regulation provides that the final account is drawn up in accordance with article 47 of the law and submitted for approval by the municipal council. It closes a cycle opened by the resolution in principle and the approval of the detailed final project, punctuated where necessary by the approval of significant departures (art. 147). That cycle is described in the article on the budget of a public project.
In both cases, the final account is a political document as much as an accounting one. The body that voted the budget reads in it whether its ceiling was held, and why not if it was not.
The final invoice and its deadlines
The final account relies on the final invoice, which follows final acceptance. Under articles 135 and 136 of the implementing regulation, this invoice is drawn up on the basis of the final acceptance report; the contracting authority checks its items and notifies any dispute "within twenty-eight days". That period is short for anyone discovering the variances at that point; it is enough for anyone who has tracked them during the works. What happens between signature and acceptance is presented in the article on what happens after signing.
Preparing the final account from day one
The final account table is built when the works start, not when they finish. Its columns are those of the dashboard described in the article on tracking the final cost during the works: dated estimate, contract price, amendments and additional contracts, statutory increases, final cost, by trade. Each update during the works is a provisional final account.
Three precautions make this work possible. Keep the dated estimate broken down by package, as used for the procedure, even though it is confidential as regards tenderers. Attach each amendment to the package it changes, not to a "miscellaneous" heading. Keep the statutory increases line separate from the first revision onwards.
In private contracts, no obligation requires this final account, but the grid is just as useful. Comparing the architect's estimate, the signed price and the final cost, while separating extras, quantities and revision, gives a private client the same reading of causes and prepares its next project.
This article sets out Luxembourg legislation on public procurement and State finances as it stood on the date of checking and is intended as professional guidance. It replaces neither legal advice nor an examination of the specific case.