Business and Technology · Competitive factors

Porter's Five Forces for ACCA Business and Technology

Updated 11 October 2026 · Fact-checked

Porter's Five Forces is a model that assesses how attractive and competitive an industry is. The five forces are threat of new entrants, bargaining power of suppliers, bargaining power of buyers, threat of substitutes and competitive rivalry. In the exam, match the scenario clue to the force it affects, then judge if that force is strong or weak.

Understand Porter's Five Forces

Michael Porter argued that a firm's profit depends on more than its own actions. It also depends on the structure of the industry it operates in. Five forces push on that industry. When the forces are strong, profits are squeezed. When they are weak, profits are easier to earn.

The five forces are:
- Threat of new entrants: how easily new firms can join the industry.
- Bargaining power of suppliers: how much pressure suppliers can put on your costs and terms.
- Bargaining power of buyers: how much pressure customers can put on your prices and quality.
- Threat of substitutes: how easily customers can switch to a different product that meets the same need.
- Competitive rivalry: how intensely existing firms fight each other.

The threat of new entrants is low when barriers to entry are high. Barriers include economies of scale, high capital costs, strong brands, patents and licences, access to distribution channels, and government regulation. If barriers are low, new firms arrive and pull prices and profits down.

Supplier power is high when there are few suppliers, the input is unique or hard to replace, or switching costs are high. Buyer power is high when there are few large buyers, products are standard, switching is cheap, or buyers can buy in bulk. The two are mirror images: suppliers sit on the input side of the firm and buyers sit on the output side.

Rivalry is high when there are many similar-sized competitors, slow industry growth, high fixed costs, low differentiation and high exit barriers. Substitutes are not the same product from a rival. They are a different product meeting the same need, such as video calls instead of business flights.

The model is used to judge industry attractiveness and to shape strategy. It is a snapshot, so forces can change as technology, regulation and customer habits change.

Key formulas to remember

Force 1: Threat of new entrants: High barriers to entry → low threat; low barriers → high threat; Barriers: economies of scale, capital needs, brand loyalty, patents, access to distribution, regulation.
Force 2: Supplier power: Few suppliers + unique input + high switching cost → high supplier power; Suppliers provide inputs to the firm. Power raises the firm's costs.
Force 3: Buyer power: Few large buyers + standard product + low switching cost → high buyer power; Buyers are customers of the firm. Power pushes prices down or demands higher quality.
Force 4: Threat of substitutes: Close substitute + low switching cost + good value → high threat; A substitute meets the same need in a different way. It is not a direct rival's identical product.
Force 5: Competitive rivalry: Many equal rivals + slow growth + high fixed costs + low differentiation → high rivalry; High exit barriers keep weak firms in the market, which also intensifies rivalry.

How to solve Porter's Five Forces questions

Use this method for any five forces question, whether it asks you to identify a force, judge its strength or suggest a response.

1Read the scenario and underline the clues, such as number of firms, costs of switching, size of customers or ease of setting up.
2Decide who the clue is about. Is it a firm that sells to the business (supplier), a firm that buys from it (buyer), a firm that might enter, a different product, or a current competitor?
3Name the force that matches. Use the five names exactly as Porter does.
4Judge the direction: does the clue make the force stronger or weaker for the business?
5For multiple response questions, check every option separately against the definition before selecting. Select exactly the number asked.
6If asked for a response, link it to the force. For example, build brand loyalty to reduce buyer power or raise barriers to entry.
7Check your answer against the wording of the question: industry attractiveness, the firm's profit, or a specific force.

Quickest way: Clue-to-force shortcut

When to use it: Use for the 1-mark and 2-mark objective test questions where you must identify the force in a short scenario.

Ask: who is acting on the business? Sells to us = supplier. Buys from us = buyer.
If the clue is about someone not yet in the market, it is new entrants.
If the clue is about a different product meeting the same need, it is substitutes.
If the clue is about firms already in the market competing on price or promotion, it is rivalry.
Then ask: does the clue raise or lower the pressure? Eliminate options that name the wrong force or the wrong direction.

Common mistakes in Porter's Five Forces

Mixing up buyer power and supplier power.
Both are about bargaining, and students forget which side of the business each sits on.
Fix: Suppliers sell to the firm and affect its costs. Buyers purchase from the firm and affect its prices. Say who is selling to whom.
Treating a rival's product as a substitute.
Both take customers away, so they feel similar.
Fix: A rival sells the same type of product in the same industry. A substitute is a different product meeting the same need, such as rail travel replacing short flights.
Saying high barriers to entry mean a high threat of new entrants.
The word 'high' is attached to barriers and the link is reversed.
Fix: High barriers mean a low threat. Write the pair together: high barriers, low threat.
Treating the model as a list of the firm's internal strengths and weaknesses.
Students mix it up with SWOT or the value chain.
Fix: Five Forces looks at the external industry environment. Internal resources and activities belong to other models.
Selecting too many or too few options in multiple response questions.
Time pressure and doubt about one option.
Fix: Count the number required before you start. Test each option against the definition and choose exactly that many.
Assuming all five forces are equally strong in every industry.
Students memorise the list rather than judging the scenario.
Fix: Assess each force from the facts given. One or two forces often dominate.

Worked examples

Example 1

A $ manufacturer of laptops buys its processors from one company that holds the patent on the chip design. No other firm can supply a similar processor. Which of Porter's five forces does this most directly describe, and is it strong or weak? Options: A) Strong bargaining power of suppliers; B) Weak bargaining power of suppliers; C) Strong bargaining power of buyers; D) High threat of substitutes.

Show the solution

Identify who the clue is about: the processor company sells to the laptop maker, so it is a supplier.
This rules out C and D, which refer to buyers and substitutes.
Judge strength: there is a single source, the input is unique because of the patent, and no alternative exists.
These facts make supplier power strong, so B is wrong.

Answer: A) Strong bargaining power of suppliers.

Example 2

Select TWO factors that would make the competitive rivalry in an industry more intense. 1) Many competitors of similar size; 2) High barriers to entry; 3) Fast industry growth; 4) Products are hard to tell apart from each other.

Show the solution

Test option 1: many similar-sized firms means no leader, so firms fight for share. This increases rivalry.
Test option 2: high barriers to entry reduce the threat of new entrants. They do not directly raise rivalry among existing firms.
Test option 3: fast growth lets firms expand without taking customers from each other, so it reduces rivalry.
Test option 4: undifferentiated products make price the main basis of competition, which increases rivalry.
Select the two options that raise rivalry: 1 and 4.

Answer: Options 1 and 4.

Exam tips

Learn the five names exactly. Questions often use them as option wording, and a small slip can make an option wrong.
Read who the clue is about before choosing: seller to the firm, buyer from the firm, newcomer, different product or existing rival.
In multiple response questions, check each statement against the definition and select exactly the number the question asks for.
Watch the direction words, such as high, low, stronger and weaker. Many wrong options reverse the direction.
For strategy questions, link the response to the specific force, such as raising switching costs to lower buyer power.

Practice questions from Competitive factors

Porter's Five Forces in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Porter's Five Forces: frequently asked questions

What is the difference between buyer power and supplier power?

Buyer power is the ability of customers to push down prices or demand better quality. Supplier power is the ability of the firms that sell inputs to the business to raise their prices or reduce quality. Buyers affect the firm's revenue side and suppliers affect its cost side.

How do I apply Porter's Five Forces in the exam?

Find the clue in the scenario, decide which party it relates to, and name the matching force. Then judge whether the clue makes that force stronger or weaker. Keep your answer tied to the wording of the question.

What is the difference between a substitute and a rival?

A rival sells a similar product in the same industry. A substitute is a different kind of product that meets the same need. Online video meetings replacing business travel is an example of a substitute.

Is Porter's Five Forces used to analyse a firm or an industry?

It analyses an industry. It helps judge how attractive the industry is and how much profit firms in it can expect. The result can then inform the strategy of an individual firm.