Short answer
A case interview is a 30-45 minute conversation in which a consulting interviewer hands you a business problem and watches you solve it live. You clarify the question, build a structure, state a hypothesis, analyze data and math, and close with a recommendation. McKinsey, BCG and Bain use cases in every interview round, always paired with a fit interview.
Key takeaways
- The case interview tests how you think under pressure, so a clear process beats memorized business knowledge.
- Most candidates now pass an online assessment first: Solve at McKinsey, Casey or the CCA at BCG, SOVA or TestGorilla at Bain.
- Seven case types cover the large majority of prompts: profitability, market entry, M&A, pricing, growth, operations and market sizing.
- A five-step method (clarify, structure, hypothesize, analyze, synthesize) works for every type and every interviewer style.
- Six weeks of deliberate practice, with 30-50 live cases, is enough for most well-prepared candidates.
What is a case interview?
A case interview is a live problem-solving exercise in which an interviewer describes a business situation and asks you to work out what the client should do. Typical prompts sound like this: a retailer's profits fell 20% in two years, a manufacturer wants to enter Brazil, a private equity fund is weighing an acquisition. You get 25-35 minutes, a sheet of paper and a pen.
The interviewer acts as both client and coach. You ask questions, they release data, charts or numbers when you ask the right things, and at the end you give a recommendation. Firms use the format because it resembles the job: a consultant walks into an unfamiliar industry, breaks a messy problem into parts, runs numbers quickly and explains the answer to a senior executive.
The terms "case interview" and "case study interview" mean the same thing. I cover the vocabulary and the underlying logic in more detail in the case study interview explained.
Stephan's note: I have sat on both sides of the table. As a candidate, I learned that interviewers forgive a wrong number far faster than a missing structure. As an interviewer, I found that I could predict the outcome within the first five minutes, based almost entirely on how the candidate set up the problem.
How does the consulting recruiting funnel work in 2026?
The funnel has four stages: application, online assessment, first round and final round. Each stage cuts the field sharply, and most candidates who fail do so before they ever see a live case.
1. Application. You submit a resume, often a cover letter, and transcripts. Screeners read for academic results, leadership and evidence of impact. See the guides on the consulting resume and the consulting cover letter.
2. Online assessment. All three top firms now screen with an online test before inviting you to interview. Formats differ by firm and sometimes by office:
| Firm | Online assessment (2026) | What it measures |
|---|---|---|
| McKinsey | Solve, a gamified assessment (the PST is retired) | Problem solving, data interpretation, decision making under time pressure |
| BCG | Varies by office: Casey chatbot case, Consulting Career Assessment (CCA) in North America, numerical tests or Pymetrics in some offices | Case logic, numerical reasoning, short video recommendation (Casey) |
| Bain | SOVA or TestGorilla depending on office, occasionally Pymetrics | Numerical and logical reasoning, situational judgement, personality |
Candidate reports suggest McKinsey Solve now runs about 65 minutes with two games (Redrock Study and Sea Wolf), with an 85-minute version adding a third game in some regions since early 2026. McKinsey does not publish a pass rate; prep providers estimate that 70-80% of test takers are screened out. For background on the old paper test, read the McKinsey PST and the BCG Potential Test.
3. First round. Usually two back-to-back interviews of 45-60 minutes, each with a fit segment and a case, led by consultants or managers. Many offices run these on video.
4. Final round. Two or three interviews, often with partners. Cases can be less structured and partners probe your judgement and your stories more deeply. Offers often follow within a few days.
What are the main case types?
Seven case types cover the large majority of prompts you will meet. Each has a core question that tells you where to start.
| Case type | Example prompt | Core question to structure around |
|---|---|---|
| Profitability | A bus operator's margin fell from 11% to 4% | Is the drop driven by revenue (price, volume, mix) or by costs (fixed, variable)? |
| Market entry | A Dutch e-bike maker wants to enter the US | Is the market attractive, can we win, and do the economics work? |
| M&A | A fund wants to buy a car wash chain | Is the target worth more than the price, including synergies and risks? |
| Pricing | A startup must price a new crop-disease test | What do cost, competitors and customer value say about the price range? |
| Growth | A software firm's growth slowed from 25% to 6% | Which levers (new customers, expansion, retention, new products) can restart growth? |
| Operations | A warehouse is 18% less productive than peers | Where in the process is capacity lost, and why? |
| Market sizing | How many paddles are sold in the US each year? | Which chain of logical assumptions gets to a defensible number? |
You will find 20 original practice prompts across these types, plus public sector cases, in case interview questions.
Interviewer-led vs candidate-led cases
Interviewer-led cases follow a fixed script. The interviewer asks a sequence of questions (structure the problem, read this chart, run this calculation, give a recommendation) and moves you along whether or not you finish each step. McKinsey is best known for this style, which I describe in the McKinsey case interview.
Candidate-led cases hand you the steering wheel. After your structure, you decide which branch to explore first and what data to request, and the interviewer reacts. BCG and Bain interviews lean this way, though individual interviewers vary. See the BCG case interview and the Bain case interview.
The practical difference is pacing. In an interviewer-led case, speed and precision on each question win. In a candidate-led case, prioritization wins: you must state which branch matters most and why, then drive the analysis yourself.
Other case formats you may meet
The live one-on-one case is the standard, but four other formats appear at some firms and offices. Each uses the same skills with a different emphasis.
- Written case. You receive a pack of 20-40 pages of exhibits, an hour or two to analyze them, and then present three or four slides or a short memo. Reading speed and the ability to ignore irrelevant data count most.
- Group case. Four to six candidates work on one problem while assessors watch. Assessors score how you build on others' ideas and move the group toward a decision, as well as your own analysis.
- Market sizing on its own. Some interviewers, especially in first rounds, ask a standalone estimate such as the number of dentists in Canada. You have five to ten minutes to build a logical chain of assumptions and land on a number.
- Chatbot or recorded case. BCG's Casey format and some recorded video interviews present a case through a screen with no live interviewer. You type or record answers under a timer, which rewards a fixed routine for structure and math.
Ask your recruiter which formats your office uses. Firms tell candidates more than most people expect.
The 5-step method for any case
The same five steps work for every case type and every interviewer style.
- Clarify. Repeat the problem in one sentence, confirm the objective (profit, growth, market share, a specific number) and the time frame. Ask two or three clarifying questions at most.
- Structure. Ask for a minute, then draw a tree that splits the problem into three or four MECE branches tailored to the client. Walk the interviewer through it top-down.
- Hypothesize. State where you think the answer lies ("My hypothesis is that rising fuel and wage costs explain most of the margin drop") and name the data that would prove or disprove it.
- Analyze. Work through exhibits and calculations. Announce your approach before you calculate, keep units visible, and state the "so what" of every number.
- Synthesize. Close with the recommendation first, two or three supporting reasons, then risks and next steps. This is the Minto Pyramid Principle applied in 60 seconds.
A short worked example
Prompt: "Kestrel Coaches, a regional bus operator, saw operating margin fall from 11% to 4% in three years. Ridership is flat. Why, and what should they do?"
A strong candidate clarifies that the goal is to restore the margin within two years, then structures revenue (tickets sold, average fare) against costs (fuel, drivers, maintenance, overhead). Because ridership is flat, the hypothesis points at average fare or cost per mile. The interviewer reveals that average fare fell 5% after a discount war with a rail operator, while driver wages (about a third of costs) rose 7%. The candidate calculates that the fare cut alone explains about two-thirds of the 7-point margin loss, and recommends ending blanket discounts in favor of off-peak pricing, while renegotiating shift patterns to contain wage growth.
What interviewers score
Interviewers fill in a scorecard after each case. Wording varies by firm, but five dimensions appear almost everywhere.
| Dimension | What a strong performance looks like |
|---|---|
| Structuring | A tailored, MECE breakdown of the problem, explained top-down |
| Quantitative skill | Correct math, done quickly, with a clear statement of what the result means |
| Business judgement | Sensible hypotheses, realistic recommendations, awareness of risks |
| Communication | Concise answers, conclusion first, easy for a client to follow |
| Synthesis | A crisp recommendation backed by the evidence gathered |
After a round, the interviewers compare scorecards in a short debrief. In my experience, a single clear weakness on one dimension can be offset by strength elsewhere, while a pattern of the same weakness across two interviewers usually ends the process. That is why consistency matters more in later rounds: every interviewer sees a fresh case, and every one must see the same reliable structure and math.
The math deserves special attention because it is the most common silent killer. My case interview math guide shows the mental shortcuts that matter. The behaviors that end interviews early are in eight case interview mistakes.
The fit interview carries equal weight
Every interview at a top firm includes a fit or personal experience segment, and a weak story can sink a strong case. McKinsey states that it looks for connection, drive, leadership, growth and problem solving, and that each interview pairs a personal experience component with a case.
Prepare four or five stories that you can adapt: leading a team, overcoming resistance, a setback you recovered from, a moment of initiative. Tell each in two minutes, with your own actions at the center and a measurable result at the end. Interviewers will probe deeper with follow-up questions, so know the details: who disagreed, what you said, what happened next.
A 6-week preparation overview
Six weeks is enough for most candidates who can commit 8-12 hours per week. The full plan with daily tasks is in case interview preparation.
| Week | Focus | Target |
|---|---|---|
| 1 | Learn the method and case types, start daily math drills | Read 5 solved cases, 15 minutes of math per day |
| 2 | First live cases with a partner, fit stories drafted | 5-6 live cases |
| 3 | Online assessment practice for your target firms | 2-3 timed practice runs |
| 4 | Volume and variety: all seven case types | 8-10 live cases |
| 5 | Weak spots, experienced case partners, firm-specific style | 8-10 live cases |
| 6 | Polish, mock final rounds, rest before the interview | 4-5 cases, fit stories rehearsed |
Where to go next
Start with the case study interview explained if the format is new to you, then follow the 6-week preparation plan. Firm histories help in the fit interview, too: McKinsey, BCG and Bain each have a distinct culture worth understanding.
If you want everything in one place, my book Cracking the Case walks from cover letter to final round: the resume method, the fit interview, guesstimates, three business-case frameworks, and three fully worked candidate cases over 30+ pages.
Frequently asked questions
How long is a case interview?
A typical interview lasts 45-60 minutes. Roughly 15-20 minutes go to the fit or personal experience part and 25-35 minutes to the case itself, followed by a few minutes for your questions.
Can I use a calculator in a case interview?
In live case interviews you normally work with pen and paper only. Interviewers expect clean mental and written math, so train calculations without a calculator from day one.
How many rounds of case interviews are there?
Most firms run two rounds. The first round usually has two interviews with consultants or managers, and the final round has two or three interviews, often with partners.
Do I need a business degree to pass a case interview?
No. Firms hire engineers, doctors, lawyers and humanities graduates. The case tests structured reasoning, numeracy and communication, all of which can be trained in a few weeks.
Are case interviews still used in 2026?
Yes. McKinsey, BCG and Bain still run live cases in every round. What changed is the screening step before them, which moved from paper tests to online assessments and game-based tests.