1. Introduction to Monopolistic Competition
Monopolistic competition is a market structure where many firms sell similar but not identical products. Unlike a monopoly, competition exists, but unlike perfect competition, firms have some control over price due to product differentiation.
This market structure combines features of both monopoly and perfect competition:
- Firms behave like monopolists by differentiating their products and setting prices.
- But in the long run, competition eliminates abnormal profits, like in perfect competition.
2. Features of Monopolistic Competition
(i) Large Number of Sellers
- Many firms operate in the market.
- Each firm controls a small share of the market.
(ii) Product Differentiation
- Products are similar but not identical.
- Firms create brand loyalty through packaging, quality, and advertising.
- Example: Toothpaste brands (Colgate vs. Pepsodent) or Fast-food chains (McDonald’s vs. KFC).
(iii) Free Entry and Exit
- New firms can enter if profits exist.
- In the long run, abnormal profits disappear as new competitors enter.
(iv) Some Degree of Price Control
- Since products are differentiated, firms have some pricing power.
- However, if prices are too high, consumers may switch to substitutes.
(v) Downward Sloping Demand Curve
- Unlike perfect competition (where firms are price takers), firms in monopolistic competition face a downward-sloping demand curve.
- They must lower prices to sell more.
(vi) Non-Price Competition
- Firms compete through advertising, branding, and customer service, not just price.
- Example: Apple markets its iPhones with brand image and innovation rather than low prices.
3. Pricing Under Monopolistic Competition
Short-Run Pricing
- Firms behave like a monopoly in the short run.
- They set prices where MC = MR but charge a higher price (P*) from the demand curve (AR).
- This allows firms to earn supernormal profits.
Long-Run Pricing
- Due to free entry, new firms enter if profits exist.
- This shifts the demand curve leftward, reducing profits.
- In the long run, firms only earn normal profits and P = AC.
4. Graphical Representation of Pricing in Monopolistic Competition
Pricing Under Monopolistic Competition (Short-run vs Long-run)

Explanation of the Monopolistic Competition Pricing Graph
This graph illustrates pricing behaviour under monopolistic competition in both short-run and long-run scenarios.
1. Short-Run Pricing (Supernormal Profit)
- Blue AR (Demand) Curve: This represents demand when a firm enjoys market power due to product differentiation.
- Red MR Curve: Lies below AR because the firm must lower prices to sell more.
- Purple AC Curve: Short-run Average Cost Curve.
- Black MC Curve: Marginal cost (MC), which is the same in both short-run and long-run.
- Profit Maximization:
- The firm sets output where MR = MC.
- The firm charges a higher price (P) from the AR curve* at that output.
- Since P > AC*, the firm earns supernormal profits.
2. Long-Run Pricing (Normal Profit)
- Green AR (New Demand Curve): As new firms enter, demand shifts leftward.
- Orange MR Curve: Also shifts leftward.
- Brown AC Curve: Adjusted for long-run equilibrium.
- Long-Run Equilibrium:
- The firm still sets output where MR = MC.
- The price (P_LR) from the new AR curve is now equal to AC.
- Since P_LR = AC, the firm earns only normal profits (zero supernormal profits).
Key Takeaways
✅ Short-run: Firms act like monopolists and earn supernormal profits.
✅ Long-run: New firms enter, shifting demand leftward, and profits normalize (P = AC).
✅ Firms compete using product differentiation and branding to sustain demand.