This study investigates the effects of customer loyalty in cosmetic brands during economic downfall in Chennai. The aim of the study is to determine the impact of customer loyalty on the sales of cosmetic brands during an economic crisis. The study is relevant because the cosmetics industry is a fast-growing industry in Chennai, and the city has witnessed a number of economic downturns in recent years. In such situations, it becomes important for companies to retain their loyal customers to sustain their business. The research will be conducted using quantitative method. A survey will be conducted to gather data on the customer loyalty towards cosmetic brands in Chennai during the economic downfall. The survey will be distributed to a random sample of customers who have purchased cosmetics from various stores in Chennai.