French tax man starts crackdown on undeclared extensions and sheds

Over the past few years the French tax office says that it has found 140,000 undeclared swimming pools, earning an additional €40 million in tax for local authorities.

It now says that it is extending the programme to undeclared home alterations such as garden sheds, extensions or conservatories.

The programme, known as Foncier Innovant, uses aerial photography via satellite images such as Google Maps, and then uses AI to cross-reference them with older versions of the same image or the local plan to flag up any alterations.

Any potential change is then checked by a tax office employee to see if it constitutes an extension or alteration to the building, and then cross-referenced with tax office records to see if the homeowner has declared the change.

Altering your French home, such as building an extension or adding a conservatory – or adding an external structure such as a garden shed or swimming pool – has two possible tax implications.

First is the one-off taxe d’aménagement, known as the ‘garden shed tax’.

This is a tax that you pay once, calculated based on the nature of the project.

READ ALSO: French property tax: How the one-off tax for building projects works

The second implication is a likely increase in your annual property tax, taxe foncière (and taxe d’habitation for second-home owners).

These taxes are based on the rentable value of the property, making a major adjustment such as extending the building or adding an amenity such as a swimming pool likely to increase the value of the home.

You therefore need to declare this to the tax office so that they can recalculate your annual bill.

The declaration should be done within 90 days of the completion of the project. In most cases, if you need planning permission permis de construire or déclaration préalable de travaux for the project, then you will need to declare it to the tax authority.

There are, however, some exemptions for smaller projects – full details here.