The purpose of this study is to evaluate the costs of some aspects of Bill 14 modifying the Charte de la Langue Française (Bill 101). The two main parts of the study examine respectively the costs incurred by businesses with 26-49 employees and other aspects of the Bill. We remove from the analysis the articles of the law that do not have a cost and those that have a cost that cannot be measured. The study combines information on the number of economic agents affected by one article or another (daycare services, employers, …), the change in behaviour of these agents caused by the law (hours, purchases) and the unit cost of these changes (hourly wage, cost of software…) to estimate the cost of each article for which it is relevant and feasible to do so. We distinguish set-up costs and on-going costs. Total quantifiable set-up costs are 24M$ while on-going costs are 5M$. An interval of set-up costs of 20-28 M$ and of on-going costs of 4-6M$ is highly likely. This neglects costs that could be identified but could not be evaluated. A margin of 10 to 30% seems appropriate to account for this. We thus obtain set-up costs of the order of 25-30M and 5-6 M$ for ongoing costs.