How France records a property sale

France publishes every recorded property transfer as open data, with the price and the built surface on the same row, geolocated to the parcel. By the standards of most countries this is extraordinarily generous. It also carries a legal condition that almost nobody writing about French property prices in English mentions, and that condition decides what anyone may build on it.

What is in the French register?

Demandes de valeurs foncières is the tax administration’s record of transfers, not a land registry in the English sense. It exists because transfers are taxed, and it was opened as part of a transparency programme. The current build carries 808,552 sales in the last twelve months across 4,251 published communes in 97 départements.

Because price and surface arrive together, France needs no address match and has no match rate. That is the structural advantage it shares with Singapore and that England and Wales does not have.

What does one DVF row carry?

A row is one line of a mutation: the deed. It carries the price declared for the whole transfer, the date the deed was signed, the commune and parcel, the nature of the transfer, the type of property and its recorded built surface. The price belongs to the mutation rather than to the line, and that distinction does most of the work in what follows.

Why can one price cover several properties?

Because the unit of record is the deed. A mutation can transfer a house, its barn and three parcels of land in one act for one price, and the register then shows that single price on every line. Divide naively and the barn acquires a price per square metre it never had. Any publisher working from this register has to reduce the file to mutations whose price can honestly be attributed to a single dwelling, and every such reduction is a judgement that should be stated. It is the French counterpart of the address-matching step England and Wales cannot avoid: the register is generous, but the generosity arrives in a shape that has to be worked before it can be divided.

Which parts of France are missing?

Alsace-Moselle, which is to say Bas-Rhin, Haut-Rhin and Moselle, operates a different land-registration regime inherited from a period of German administration: the livre foncier rather than the national system. Transfers there are not in this dataset. Mayotte is absent for its own reasons.

This is not a coverage gap that better engineering closes. Strasbourg, Mulhouse, Metz and Colmar cannot be covered from this source at all, by anyone, and a French property site that shows figures for them is using something else and should say what.

What condition does the licence attach?

Reuse of the data is subject to two conditions in the tax procedures code. The first is that reuse must not permit indirect re-identification of the individuals concerned. The second is that reuse must not allow the data to be indexed by external search engines.

The second is the one that surprises people. It does not forbid publishing statistics derived from the register; it constrains letting the underlying records be indexed. In practice that means a publisher may compute and publish medians, distributions and trends, and must not expose the transaction rows themselves to a crawler. This network serves its French data endpoints with a noindex header for exactly that reason, and publishes derived statistics only on its indexable pages.

The first condition has a subtler effect: it puts a floor under how thin a published figure may be. A median computed from a handful of sales in a small commune starts to approach a statement about individual transactions, so a sample floor is not merely good statistics here, it is part of complying with the terms. How many sales a local figure needs is a methodological question everywhere and a legal one here.

What should a reader take from this?

Three practical things. French figures are published twice a year rather than monthly, so a French figure is structurally less current than a Singaporean one and that gap is a property of the release cycle, not of the publisher. Coverage is national except for the three départements above, and any site quiet about that is worth a second look. And the sample floors you see on French pages, where a commune shows no figure at all, are the honest form of the constraint rather than a missing feature.

How England and Wales record a sale is the contrasting case: a register with no surfaces at all, and a licence with no indexing condition. The French register as this network publishes it is at IndexProp FR, commune by commune, with the sample floor applied.