The quantitative restrictions applied to imports lead to distortions in the market mechanism; since it prevents the economic agents from putting into practice their consumption plans. This article presents a simple model, based in the Armington function, which analyzes the effects these restriction produce on the consumer's welfare. It measures the loss in the Colombian consumer's welfare, due to the restrictions prevailing during 1985. This paper discusses the concept of equivalent price and its use in evaluating rationing by means of general equilibrium models.