A monopolistic market and a perfectly competitive market are two market structures that have several key distinctions, such as market share, price control and barriers to entry. In a monopoly, there is only one firm that dictates the price and supply levels of goods and services and has total market control. Contrary to a monopolistic market, a perfectly competitive market is comprised of many firms, where no one firm has market control.

Monopolistic Market

In a monopolistic market, prices are generally high for goods and services because firms have total control of the market. In this type of market, firms are price makers because they control the prices of goods and services. Firms have total market share, which creates difficult entry and exit points. Since barriers to entry in a monopolistic market are high, firms able to enter the market are still often dominated by one bigger firm. A monopolistic market generally involves a single seller, and buyers do not have a choice of where to purchase their goods or services.

Perfect Competition

In a market that experiences perfect competition, prices are dictated by supply and demand. Firms in a perfectly competitive market are all price takers because no one firm has total market control. Unlike a monopolistic market, firms in a perfectly competitive market have a small market share. Barriers to entry are relatively low and allow firms to enter and exit easily. Contrary to a monopolistic market, a perfectly competitive market has many buyers and sellers, and consumers are able to choose where they buy their goods and services.

Monopolistic Competition

In between a monopolistic market and perfect competition lies monopolistic competition. In monopolistic competition, there are many producers and consumers in the marketplace, and all firms only have a degree of market control, whereas a monopolist in a monopolistic market has total control of the market. Unlike a monopolistic market, monopolistic competition offers very few barriers to entry. All firms are able to enter into a market if they feel the profits are attractive enough. This makes monopolistic competition similar to perfect competition.

However, in a monopolistically competitive market, there is product differentiation. Products in monopolistic competition are close substitutes; the products have distinct features, such as branding or quality. This is unlike both a monopolistic market, where there are no substitutes for products, and perfect competition, where the products are identical. Pricing in perfect competition is based on supply demand, while pricing in monopolistic competition is set by the seller.

(For related reading, see: A History of U.S. Monopolies.)