The twentieth is a direct tax wanted by the General inspector of finances Jean-Baptiste de Machault d' Arnouville. It wishes to establish a direct tax concerning the whole of the population (third-state and noble) whose amount corresponds to 5% (1/20) of the incomes.

It is adopted to replace the tenth removed in May 1749. Its installation is effective at January 1st 1750 and aims at deadening the national debts. Contrary to the tax practices this new tax is created in period of peace and thus becomes final.

The clergy and the provinces emit sharp protests and poke riots. Louis XV suspends the tax in December 1751 for the land one of the Catholic church but preserves it for the provinces.

With the beginning of the seven year old war in 1756, a second twentieth is set up. The war continuing, a third twentieth is set up in 1760. The finished war, this last twentieth is removed in 1763, the two others remaining.

The twentieth door on the incomes of industry and the trade established according to the declaration of the chargeable ones. It taxes also the properties whose recipients must declare, nature, the extent and the annual average net profit. A control system is set up at the level of each Généralité under the authority of the Intendant.

This tax of modern design, deeply runs up against the mentalities attached to the privileges. Many are the private individuals and the constitutional body which substituted the tax Abonnement to him or the final repurchase. Many noble are arranged not to pay it. In 1763, the Parliament of Paris, after having battled against controls, obtains that the dimensions of twentieth are not revalued any more. That led to a shortfall for the Treasury at one time when the farm prices fly away. In 1787, in front of the financial bankruptcy of the Monarchy, it is decided to remove all the exemptions. It was too late. In 1789, both twentieth brought back approximately 57 million books.