Journal article: This article uses an allocation of time framework following Becker, to propose a new method to estimate the opportunity cost of time and price elasticities at a micro level. As expected, the estimate of the value of time performed by matching the INSEE Family Budget and Time Use surveys is close to the minimum wage rate and positively correlated with household wages, incomes and relative incomes, as well as with the presence of children. Using this estimate, full prices are derived, allowing the computation of cross-section data of price elasticities, elasticities with respect to time use, as well as to the opportunity cost of time.