Case Interviews: What to Expect and How to Prepare

In this guide

A case interview is a structured conversation in which you solve a business problem with your interviewer. You clarify the question, set out a structure, ask for and analyse information, do some quick calculations, and finish with a recommendation. Consulting firms say there is rarely one right answer. They are assessing how you think, how you use numbers and how clearly you communicate.

What is a case interview?#

Bain describes a case interview as a structured conversation about a real business problem, the kind its teams work on, and says it is looking at how you think and structure problems rather than for a single right answer. BCG says you will be given a realistic business challenge and asked to structure your approach, ask thoughtful questions, analyse data, do quick calculations and identify the most important factors.

Firms use cases for consulting roles. Bain notes that case interviews are used for consulting roles only.

What happens during the interview?#

An LSE Careers article describes four stages recommended by one leading firm: clarify, structure, analysis and conclusion.

Clarify. Repeat the problem in your own words and ask questions until you understand the objective. Bain’s first tip is to clarify the objective before diving in.
Structure. Take a minute to break the problem into parts, then talk the interviewer through your plan.
Analyse. Ask for the information you need, read charts and tables carefully, and do the calculations out loud.
Conclude. Answer the question you were asked, give the one or two numbers behind your answer, and name the main risk and the next step.

Oliver Wyman suggests treating your interviewer as your client: they want you to solve the problem and can help you, so work with them.

Who leads the case?#

It depends on the firm. At McKinsey, the Problem-Solving Interview is led by the interviewer, who presents the case and asks a series of questions. In other interviews you will be expected to drive the case yourself: decide what to look at next and ask for the data you need. Be ready for both.

What kinds of case come up?#

Most cases are variations on a few themes:

Type	Example question
Profitability	Why have a company’s profits fallen, and what should it do?
Growth and market entry	Should a UK retailer open stores in another country?
Market sizing	How many electric vehicle chargers will a UK city need by 2030?
Operations	How can a hospital reduce waiting times in A&E?

Bain’s own practice cases include helping a friend decide whether opening a coffee shop is a good idea, and advising a fashion business on why its revenues have fallen for five years.

How should you structure your answer?#

Break the problem into parts that do not overlap and that together cover the whole question. For a profit problem, that might be revenue (price and volume) and costs (fixed and variable). Then say which branch you would look at first and why.

The LSE article warns that strong candidates do not force frameworks or add unnecessary detail. A simple structure built for the question in front of you beats a memorised framework every time. Write it down clearly, because Bain asks candidates to be ready to walk the interviewer through their notes.

How do you handle the maths?#

Practise percentages, growth rates, margins and break-even calculations without a calculator, as LSE Careers advises.
Round sensibly and say so: “I will use 70 million for the UK population to keep the maths simple.”
State every assumption before you use it.
Write each step down, check the size of your answer, and say what it means for the client.
If you make a mistake, say so and correct it. Oliver Wyman reminds candidates to be careful with simple calculations.

How should you practise?#

Start with the firms’ own cases. McKinsey publishes practice cases such as Beautify and Diconsa, Bain publishes cases and videos, and BCG offers a free job simulation called OneDay@BCG.
Practise live with a partner. Take turns as interviewer and candidate, and give each other honest feedback.
Record yourself to check how clearly you explain your structure.
Plan enough time. LSE Careers suggests 50 to 60 hours of practice is a common expectation, while the Cambridge careers service suggests around 25 to 30 cases.
Keep up with business news so you can talk sensibly about customers, costs and competitors.

What about virtual interviews?#

Bain’s advice for virtual interviews is practical: test your internet, camera and microphone in advance, choose a quiet space with a neutral background, turn off notifications, and tell your interviewer when you are taking notes. Have pen and paper ready, whichever format you are in.

Questions

Do I need to learn business frameworks?

It helps to know the basic building blocks, such as revenue and costs, but firms warn against forcing a memorised framework onto a case. Build a simple structure for the specific question and explain why it fits.

What if I get stuck during a case?

Say what you are thinking, go back to your structure, and ask a focused question. Interviewers often guide candidates, and working with them is part of the test.

Are case interviews used outside consulting?

Some employers in other sectors use case studies, often as written or group exercises at assessment centres. Bain notes that it uses case interviews for consulting roles only.

Sources

We checked these sources on 25 September 2026. Employers change their processes, so always check their own pages before you apply.

Written by Deeplink Coaching

We help students and graduates get graduate jobs in consulting, accounting and finance, engineering and data. Our guides are based on what employers and professional bodies say about their own processes. About us