BCG Case Interview: Chairman Case, Written Case, and PEI Guide (2026)

The BCG 2026 Interview Loop

A typical BCG loop for Associate or Consultant has two rounds. Round 1 is usually two interviewer-led cases with experienced consultants. Round 2 is typically two candidate-led cases with Principals plus one Chairman Case with a Partner. Each case is 30 to 45 minutes. Every case is paired with a Personal Experience Interview segment. In some offices (London, Paris, Gulf), you also do a written case plus presentation.

Format 1: The Interviewer-Led Case (Round 1)

BCG's interviewer-led format is similar to McKinsey. You get a business prompt, you structure, interviewer walks you through data, and you synthesize. The interviewer controls the pacing. Your job is to respond with crisp structure, clean math, and defensible recommendations.

What BCG scores differently from McKinsey: they weight creativity slightly more than perfect MECE. A first-round BCG candidate who proposes a non-obvious hypothesis and defends it well will beat a candidate whose tree is textbook-perfect but generic.

Sample Interviewer-Led Prompts

• ●"A luxury hotel chain's RevPAR fell 12% year over year despite occupancy holding."
• ●"A utility company is considering entering EV charging infrastructure."
• ●"A consumer electronics brand wants to assess its premium headphone category profitability."
• ●"A regional insurer is seeing churn spike among policies over 7 years old."

Format 2: The Candidate-Led Case (Round 2)

Candidate-led is the BCG signature format. The interviewer gives you a one-line prompt and then stays silent. You decide what questions to ask, what data to request, what hypotheses to test, and when to synthesize. This is why BCG candidates who train only on McKinsey-style cases struggle in Round 2.

The skill being tested is initiative plus business judgment. A 4-score candidate drives the case forward without waiting to be prompted, knows when to escalate from analysis to hypothesis, and closes with a decisive recommendation even when data is incomplete.

How to Drive a Candidate-Led Case

• ●First 60 seconds: restate the prompt, define success, structure the problem.
• ●Next 3 minutes: state your hypothesis out loud and the data you need to prove or disprove it.
• ●Ask specific questions: "Can you share the customer cohort data by segment?" not "Do you have customer data?"
• ●When you have the data, update your hypothesis visibly. Say what changed and why.
• ●Synthesize at the 25-minute mark. One recommendation, two reasons, one risk, one next step.

Format 3: The Chairman Case (Partner Round)

The Chairman Case is a partner-led case focused on business judgment, not framework precision. A Chairman or Senior Partner gives you a real client situation from their practice and asks what you would do. There are no textbook answers. The interviewer is evaluating whether you think like a senior consultant already.

What gets scored: the quality of your questions, the boldness of your hypothesis, your comfort defending a view against pushback, and whether your recommendation would actually work. A common Chairman Case pattern is a CEO-level decision where all the obvious moves have downsides, and you have to pick the least bad option with conviction.

Sample Chairman Case Prompts

• ●"A family-owned retail chain is deciding whether to sell to private equity. What should they do?"
• ●"A global pharma client's blockbuster drug is coming off patent. Defend a 5-year plan."
• ●"A bank is deciding whether to shut down 40% of branches. How would you advise?"
• ●"A CEO is deciding whether to fire a star performer whose team is reporting bullying. Defend your recommendation."

The Written Case Plus Presentation (Select Offices)

Several BCG offices run a written case as part of the final round. You get a 15 to 20 page packet with industry context, exhibits, and a client question. You have 2 hours to analyze it and prepare slides. Then 30 minutes with a Partner: 10 minutes presenting, 20 minutes of Q&A.

The trap in written cases is trying to use all the data. The best candidates pick the 3 exhibits that matter, ignore the rest, and present a crisp recommendation with one risk. Partners will try to break your recommendation during Q&A. A 4-score candidate holds their view under pressure, adjusts where the data warrants, and does not collapse.

The BCG Potential Test

Some candidates also face the BCG Potential Test, a 45-minute online assessment with 23 questions covering numerical reasoning, verbal reasoning, and case judgment. The pass bar is roughly 60%. This test gates the first-round invite for many offices. It is different from the old BCG Online Case Test.

Personal Experience Interview (PEI) at BCG

BCG calls its behavioral segment Personal Experience Interview. It covers leadership, entrepreneurial drive, and personal impact. Three to five minutes at the start or end of every case round. The bar: quantified stories, clear personal contribution, and self-awareness on what you would do differently.

Common PEI prompts: "Tell me about a time you led a team through ambiguity," "Describe a time you had to convince someone senior to change their mind," "What is a moment you failed, and what did you learn?" For detailed STAR templates, see our behavioral interview practice guide.

BCG vs McKinsey vs Bain: What Actually Differs

Candidates who prepare for all three firms often lose ground by over-indexing on one format. The practical differences: McKinsey leans hardest on MECE and analytical rigor, BCG rewards creativity and driving the case, Bain weights business judgment and fit most heavily. The written case is a BCG signature in certain offices. The Chairman Case is a BCG partner round you will not see at McKinsey.

For McKinsey-specific prep, see our McKinsey case interview examples. For a full MBB comparison, our consulting interview practice guide covers all three.

The 4-Week BCG Prep Plan

• ●Week 1: MECE drills, case math, structure library. 30 minutes daily.
• ●Week 2: 10 interviewer-led mocks, focus on synthesis. Add PEI story bank of 6 stories.
• ●Week 3: 10 candidate-led mocks, focus on driving the case and asking precise questions.
• ●Week 4: 3 Chairman Case mocks, 2 written cases, 10 PEI reps.

Practice a BCG-Style Case Live

The candidate-led format is the hardest to train for alone. ZeroPitch gives you a live BCG-style case room that simulates both interviewer-led and candidate-led formats, with a Chairman Case option for final-round practice. You get scored on initiative, hypothesis quality, math accuracy, and synthesis. Every round ends with a report showing exactly where you lost points.