In this diploma thesis it is explained how prices are formed in retail, and what levels of retail prices and methods of price formation exist. The process of price formation occupies a key place in trade and marketing, because according to the price is determined the value of goods, the revenues and profitability of the company. The problem is how to form retail prices in conditions of increasing market concentration and competition, because there is increasing pressure on the margin and the variety of the offer. Online sales are a significant form of retail sales. The cost of sales for the retailer can be lower compared to sales in a physical store. With online retail, goods can be offered to customers anywhere in the world so there is space for price variability depending on the market. Inovation in price promotions should be taken seriously. A physical store can be a profitable investment if customers are offered a new, different experience in combination with new technological trends. The online store enables faster shopping, all information in one place and a larger selection of items and easier tracking of the competition. It is also shown how customer reviews can influence further sales of products. As an example of comparing online and offline prices was taken the company La PIEL d.o.o. and BIPA store. The owner of La PIEL company is the singer Lana Jurčević. Their main activity is the production of products on a natural basis without harmful substances. In order to be noticed as well as possible, they use many ways of price promotion of the cosmetic line.