BCG Case Interview Guide 2026: Format, Casey, Scoring, and Prep Strategy

BCG's acceptance rate is approximately 1-2% of applicants, with first-round pass rates of 30-40% — and BCG uses an interviewer-led case format where the interviewer hands you exhibits sequentially and asks targeted questions rather than letting you drive the structure, per BCG's own interview process page. What separates the candidates who advance? They understand BCG's specific format: interviewer-led cases, heavy data exhibits, and a screening process that starts with the Casey chatbot before you ever speak to a human.

This guide covers the Casey assessment in detail, what BCG interviewers actually score, how the format differs from McKinsey and Bain, and a prep strategy built specifically for BCG's data-driven, exhibit-heavy style. If you're also preparing for other MBB firms, pair this with our Bain case interview guide and McKinsey Solve guide.

BCG Interview Process Overview

BCG's interview process has three stages, with the Casey chatbot assessment serving as a pre-filter before live interviews begin.

Each live interview lasts about 45 minutes: roughly 30 minutes for the case and 10-15 minutes for fit and behavioral questions. But before you get to any of that, you need to pass Casey.

The Casey Chatbot Assessment

Casey is BCG's online, chatbot-based case assessment, and for many candidates it is the first real gate in the process. BCG describes it as "an interactive business case guided by a chatbot" that evaluates problem-solving and analytical skills (BCG Case Interview Preparation). Some offices use Casey in place of a phone screen entirely, meaning your performance on this chatbot determines whether you ever speak to a human interviewer. According to IGotAnOffer's Casey guide, the assessment runs 30-35 minutes and includes a mix of multiple-choice, numerical, and open-ended questions, plus a 1-minute video recommendation at the end.

Format and Structure

Casey presents a business case through a chat interface. You interact with a virtual interviewer who walks you through the case step by step. The assessment typically includes 6-10 questions across three formats:

Multiple-choice questions ask you to identify the correct interpretation of data, select the right next step in an analysis, or choose the best recommendation from several options. These test your ability to read exhibits quickly and apply structured thinking under time pressure.

Short-answer (text) questions require you to explain your reasoning in writing. You might be asked to interpret a chart, calculate a key metric, or explain why one business approach is better than another. The quality of your written reasoning matters here, not just the final answer. Show your work: state your approach, walk through the logic, and arrive at a clear conclusion.

Video recording questions (included in some versions of Casey) ask you to record yourself delivering a structured response on camera. This tests communication skills that text answers cannot capture: clarity, confidence, structure, and presence. You typically get one attempt with a short preparation window.

What Casey Evaluates

Casey tests the same core skills as a live BCG interview, just through a digital interface:

• Data interpretation: Can you read charts, tables, and exhibits accurately and extract the key insight?
• Quantitative reasoning: Can you perform calculations correctly and apply the result to the business question?
• Structured thinking: Do your answers follow a logical sequence, or do you jump to conclusions?
• Communication (video): Can you deliver a clear, structured answer when speaking to a camera?
• Synthesis: Can you pull together multiple data points into a coherent recommendation?

Casey Timing and Stakes

The assessment takes approximately 25-30 minutes. There is no strict per-question timer for text answers, but the overall assessment is timed, so you cannot spend 10 minutes on a single question.

How to Prepare for Casey

Treat each question as a mini-case. Even multiple-choice questions have an underlying logic. Don't just pick the answer that "feels right." Identify the relevant data, apply a framework or calculation, and select the answer that the evidence supports.

Practice written case explanations. Casey's short-answer questions reward candidates who write structured, clear responses. Practice writing out your reasoning for case questions in 3-5 sentences: state the approach, show the key calculation or logic, and state the conclusion. Bullet points are fine, but each bullet should advance the argument.

Record yourself answering mini-case questions. For the video component, practice delivering 60-90 second structured answers to a camera. Use a top-down approach: state your answer first, then give 2-3 supporting reasons. Watch your recordings and check for filler words, wandering structure, and eye contact with the camera lens.

Do BCG's official practice cases first. BCG provides practice cases — including a climate strategy case, a digital bank scenario, and a cloud migration case — on their case interview preparation page. Complete these before attempting Casey. They give you a feel for BCG's exhibit style and question phrasing. A BCG consultant shares additional prep advice on the BCG Careers blog.

BCG Interview Day: What to Expect Hour by Hour

Most candidates know BCG has "2-3 interviews per round," but few know what the day actually looks like. Here is a typical first-round and final-round interview day timeline:

First Round (In-Person or Virtual)

Final Round (In-Person)

How BCG Cases Differ from McKinsey and Bain

Candidates who prepare with generic "MBB" materials miss firm-specific differences that interviewers notice. Here is how BCG compares:

For a deeper comparison on the Bain side, see our Bain case interview guide. For McKinsey's digital assessment, see our McKinsey Solve guide.

What Interviewer-Led Means in Practice

In a BCG case, the interviewer controls the flow:

1. They present the situation and the question.
2. They ask you specific sub-questions: "What would you need to know?" or "Look at this chart, what do you see?"
3. They move you to the next area when they're satisfied.
4. At the end, they ask for your recommendation.

You still need structure and business sense, but you don't need to lay out a full framework upfront. Instead, answer each question clearly and show your thinking. The skill being tested is whether you can solve problems collaboratively with the interviewer, not whether you can perform a solo analysis.

What BCG Evaluates

BCG interviewers assess four main dimensions. These align closely with the evaluation criteria published on BCG's case interview preparation page, supplemented by patterns from over 3,000 candidate reviews in Glassdoor's BCG interview database and IGotAnOffer's BCG prep guide.

1. Problem Solving

Can you break down a complex problem into logical parts? Do you approach each question with structure rather than guessing?

• Structure your answer before speaking. Even a 5-second pause to organize your thoughts signals discipline.
• State your approach: "I'd look at this in two parts: the market side and the company side."
• Prioritize: tell the interviewer which part matters most and why.

2. Analytical Rigor

Can you work with data accurately and draw the right conclusions? This is where BCG's exhibit-heavy style raises the bar.

• Read charts carefully. State what the chart shows before interpreting it.
• Do math cleanly. BCG cases are data-heavy, so practice mental math for case interviews until calculations feel automatic.
• Sanity-check your numbers: "That implies $50 per customer, which seems reasonable for this industry."

3. Business Judgment

Do your answers make business sense? Can you connect analysis to real-world implications?

• After analyzing data, explain what it means: "This 20% margin decline suggests we're losing pricing power."
• Consider second-order effects: "If we raise prices, some customers may switch to competitors."
• Show you understand the client's industry context. Generic answers that could apply to any company are a red flag.

4. Communication

Can you explain your thinking clearly and concisely? BCG's interviewer-led format makes communication visible at every step, not just the final recommendation.

• Lead with the answer, then support it: "Revenue decline is driven by volume loss in the enterprise segment. Here's why..."
• Be concise. Don't narrate every calculation step.
• Engage with the interviewer: make eye contact, ask clarifying questions, and acknowledge their hints. The interview should feel like a collaborative working session, not a presentation.

Sample BCG Case Flow

Here is what a typical BCG case looks like in practice. Notice the interviewer-led rhythm: question, data, interpretation, next question.

Interviewer: "Our client is a European airline seeing profit margins decline. They want to understand why and what to do. Let's start: what are the main drivers of airline profitability?"

You: "Airline profitability is driven by revenue per passenger (yield times load factor) minus operating costs per seat (fuel, labor, aircraft, airport fees). I'd want to know whether the decline is on the revenue side or the cost side."

Interviewer: "Good. Here's a chart showing revenue per available seat kilometer over the past 3 years." (shows chart)

You: "The chart shows RASK declining 12% from 2023 to 2025, from 0.08 euros to 0.07 euros. The decline accelerated in 2025. This suggests either yield compression (lower fares) or load factor decline (emptier planes), or both. Do we have data on load factor separately?"

Interviewer: "Load factor has been flat at 82%. So what does that tell you?"

You: "If load factor is flat but RASK is declining, the issue is yield, meaning average fares are dropping. I'd want to understand whether this is market-wide fare compression from low-cost carrier competition, or specific to our client, for example, a route mix shift toward lower-yield routes."

Interviewer: "Here's a table showing our client's route-level revenue versus two competitors." (shows table)

You: "Looking at this table, our client's fares are 8-15% lower than Competitor A on the same routes, but roughly in line with Competitor B, which is the low-cost carrier. This suggests the client is being forced to match low-cost pricing on overlapping routes. The key question is whether they can differentiate on service to justify a price premium, or whether they need to accept lower yields and cut costs to protect margins."

This is the BCG rhythm: answer the question, interpret the data, draw a business implication, and ask a logical follow-up. Each exchange moves the case forward.

BCG Exhibit Workflow (30-Second Read)

When you get a chart or table, use this sequence:

1. Frame: "This chart compares X across Y from year A to B."
2. Extract: Identify 1-2 non-obvious signals (not every data point).
3. Implication: Connect insight directly to the case question.
4. Ask: Request the next data needed to test your hypothesis.

Practice this workflow until it becomes automatic. Our case interview examples include exhibit-heavy cases you can use for reps.

BCG-Style Case Example: Retail Bank Digital Transformation

Here is a BCG-flavored case prompt that reflects their data-heavy, exhibit-driven style. This is the kind of case BCG interviewers build: multiple exhibits, specific questions at each stage, and a synthesis ask at the end.

Setup: "Our client is a mid-size European retail bank with 4 million customers. Over the past 3 years, their cost-to-income ratio has risen from 58% to 67%, while digital-native competitors are operating at 35-40%. The CEO wants to know: should the bank invest 200 million euros in a digital transformation over 3 years, and if so, where should the investment be focused?"

Exhibit 1 (table): Cost breakdown by category: branch operations (40% of total costs), IT infrastructure (25%), customer service call center (18%), compliance and risk (12%), other (5%).

Question 1: "Looking at this cost breakdown, where do you see the biggest opportunity for the digital investment to reduce costs?"

A strong answer: "Branch operations at 40% of costs is the largest category and the one most directly impacted by digital migration. If the bank can shift a meaningful share of transactions from branches to digital channels, that's where the highest-magnitude cost reduction sits. The call center at 18% is the second target, since digital self-service tools (chatbots, app-based issue resolution) can reduce call volume. I'd want to see data on what percentage of transactions currently happen in-branch versus digitally."

Exhibit 2 (bar chart): Transaction channel mix: 65% in-branch, 20% online banking, 15% mobile app. Competitor benchmark: 25% in-branch, 35% online, 40% mobile.

Question 2: "The bank is at 65% in-branch versus the competitor benchmark of 25%. If the bank could shift to 35% in-branch over 3 years, what's the annual cost saving, assuming branch costs are 320 million euros today and scale roughly linearly with transaction volume?"

A strong answer: "Going from 65% to 35% in-branch is a reduction of roughly 46% of in-branch transactions (30 percentage points out of 65). If branch costs scale linearly, that's 46% of 320 million euros, which equals approximately 147 million euros in annual savings. However, not all branch costs are variable. Fixed costs like leases and core staff would remain unless branches are actually closed. So the realistic savings are probably 60-70% of that figure, roughly 90-100 million euros annually, if the bank also consolidates its branch network."

Question 3 (synthesis): "Given what we've analyzed, what's your recommendation to the CEO?"

This kind of multi-exhibit, question-by-question case is quintessentially BCG. Practice building your answer incrementally as new data arrives, rather than trying to solve everything at once.

BCG-Style Case Example: Specialty Chemicals Pricing

Here is a second BCG-flavored prompt focused on pricing, a case type BCG asks frequently.

Setup: "Our client manufactures specialty chemicals sold to industrial customers. Margins have declined from 22% to 14% over two years despite stable volumes. The CEO wants to understand the margin decline and identify pricing actions."

Exhibit 1 (waterfall chart): Margin bridge showing: base margin 22%, raw material cost increase (-4%), customer discount creep (-3%), product mix shift toward lower-margin products (-2%), operational inefficiency (-1%), new margin 12%. (Note: the CEO quoted 14%, so there is a 2pp gap to reconcile.)

Key question: "This waterfall shows margin declining to 12%, but the CEO said margins are 14%. What might explain the discrepancy, and which driver would you address first?"

A strong answer addresses the 2pp gap (possibly timing differences, one-time items, or different margin definitions) and then prioritizes the largest controllable driver: customer discount creep at 3pp, since raw material costs are harder to influence and discount discipline is an internal lever the client can act on immediately.

This type of case, starting with a data discrepancy and requiring you to question the numbers, is a classic BCG move. They want to see whether you trust exhibits blindly or interrogate them.

How to Prepare for BCG Cases

1. Practice Interviewer-Led Format

Many candidates only practice candidate-led cases (the McKinsey style). BCG's format is fundamentally different:

• Practice answering specific questions within a case, not just laying out frameworks.
• When given a chart, practice the "describe, interpret, implication" flow until it's automatic.
• Practice being flexible. The interviewer may take you in an unexpected direction, and the right response is to follow their thread, not force your framework.

For a broader preparation approach across all case formats, see our guide on how to practice case interviews.

2. Build Data Interpretation Skills

BCG cases are chart-heavy. Practice reading:

• Bar charts and trends over time.
• Scatter plots comparing metrics across segments.
• Tables with multiple variables.
• Waterfall charts showing drivers of change.

For each chart, practice: "What does this show? What's the key insight? What does it mean for the case?" Our case interview math guide includes exhibit-based math drills.

3. Sharpen Your Math

BCG integrates math into case questions rather than isolating it. Practice:

• Percentages and growth rates in context.
• Market sizing within a case flow.
• Break-even and payback calculations.
• Margin calculations across segments.

BCG-style quant reps are strongest when you rotate case types: profitability framework, market entry framework, and pricing strategy cases.

Use mental math for case interviews to speed up exhibit math and case interview synthesis to tighten your recommendation close.

4. Prepare Fit Stories

BCG's fit portion covers leadership, impact, and teamwork. Prepare 3-4 stories using the STAR format (Situation, Task, Action, Result):

• Leadership: A time you led a team through a challenge.
• Impact: A time you created measurable impact.
• Overcoming obstacles: A time you faced resistance and persisted.

Keep each story under 2 minutes. Focus on your specific actions and quantifiable results. For McKinsey candidates preparing similar behavioral stories, see the McKinsey PEI guide. For Bain's distinct behavioral format, see the Bain case interview guide.

5. Use BCG's Official Practice Resources

BCG provides free practice cases and Casey preparation materials on their case interview preparation page, including interactive case scenarios and a downloadable written case PDF (BCG Written Case Example). Complete these before your interview. Not using the official resources signals that you didn't do basic homework, and BCG interviewers can tell.

6-Week BCG Prep Plan

Interactive BCG Prompt Drills

Test Your Knowledge

Common Mistakes That Kill BCG Candidacies

Sources and Further Reading (checked March 10, 2026)

• BCG case interview preparation and practice cases: careers.bcg.com/global/en/case-interview-preparation
• BCG interview process overview: careers.bcg.com/global/en/interview-process
• BCG Careers blog, how to prepare for a case interview (BCGer advice): careers.bcg.com/global/en/blogarticle/how-to-prepare-for-a-case-interview-a-bcger-s-advice
• BCG written case interview example (PDF): media-publications.bcg.com/BCG-Written-Case-Example.pdf
• Glassdoor BCG interview reviews and experiences: glassdoor.com/Interview/Boston-Consulting-Group-Interview-Questions-E3879.htm
• IGotAnOffer BCG case interview guide: igotanoffer.com/blogs/mckinsey-case-interview-blog/bcg-case-interview
• IGotAnOffer BCG Casey chatbot guide: igotanoffer.com/en/advice/bcg-online-case-assessment
• IGotAnOffer BCG interview process and timeline: igotanoffer.com/en/advice/bcg-interview-process
• Management Consulted BCG prep resources: managementconsulted.com/bcg-case-interview
• PrepLounge BCG case interview guide: preplounge.com/en/blog/consulting/firms/bcg
• Wall Street Oasis BCG interview discussion threads: wallstreetoasis.com/forum/consulting

Related Guides

• Bain Case Interview Guide
• McKinsey PEI Guide
• McKinsey Solve Guide
• Consulting Interview Prep Timeline
• Profitability Framework