French authorities use AI to help recoup €200 million in unpaid tax from one department alone

The increasing use of artificial intelligence (AI) by tax authorities is leading to huge sums of money being collected from homeowners who omit information about property upgrades.

Departments have been using AI to assess aerial photos and check if properties are housing undeclared swimming pools, verandas, sheds and a number of other improvements. 

If these have not been accurately declared to the tax authorities – leading to a corresponding increase in property taxes reflecting the new value of the property – fines can be levied as well as backdated payments of tax collected.

One department recouped over €200 million in 2023 via tax audits, many of these after being caught by AI.

Efforts in the Alpes-Maritimes in the far south-east of France on the border with Italy, were particularly successful as many property owners choose to install swimming pools due to the warmer climate. 

“We compare property assets with declared property income. We can cross-check several pieces of information [including aerial photographs],” said Jean-Paul Catanese, Director of Public Finances for the Alpes-Maritimes department to FranceInfo.

Further success relating to 2024 declarations is possible as the use of AI in this way becomes more widespread.

An estimated 20,000 ‘undeclared pools’ were discovered in 2022, rising to 140,000 in 2023.

Increasing use of AI 

Alongside swimming pools, AI can also be used to scan aerial images for undeclared extensions to properties as well as installations in gardens and on owned land adjacent to the property. 

Read more: French property tax fraud: what is targeted other than 'secret’ swimming pools?

Major installations and improvements must be declared to the authorities within 90 days of completion, so they can be taken into consideration for increases to the taxe foncière (main property tax) of the property, and the taxe d’aménagement that is paid on some extensions.

This is additional to gaining permission for the works from a local mairie, as this information is not shared to the tax authorities. 

You can read how to declare your property improvement in our article on taxe d’aménagement here. 

Fiscal authorities have recently begun using AI to monitor social media activity for cases of tax fraud. 

Read more: New law enables French tax authorities to monitor (some) social media activity

This includes seeing if the person’s lifestyle matches their tax returns. 

Only public information and not private data (such as personal messages) is monitored.