The reason lies in France's enshrined labour code, the Code du Travail, which was first published in 1910. The Code du Travail used to say that it was illegal for anyone to work more that six days a week and that workers should have 35 consecutive hours of rest.

In Paris, the tradition of closing on Mondays is most notable among public museums and local boutiques, but it is not a "city-wide" shutdown. Many of the most famous state-owned museums, such as the Musée d'Orsay, Versailles, and the Musée Rodin, are closed on Mondays to allow for deep cleaning, restoration work, and staff rest after the busy weekend rush. Conversely, the Louvre and the Centre Pompidou choose to close on Tuesdays instead. Beyond museums, many family-owned "Mairie" businesses (like local bakeries, butchers, and small fashion boutiques) stay closed on Mondays because they are often open on Saturdays; the Monday closure provides them with a "two-day weekend." In 2026, major department stores like Galeries Lafayette and most chain retailers remain open seven days a week to accommodate tourists. If you are planning a Monday in Paris, it is the perfect day to visit the Eiffel Tower, take a Seine river cruise, or explore the Marais district, where many independent shops stay open to cater to the crowds that find the museums closed.