BCG case interview: the only post you'll need to read

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BCG case interviews don't have to be complicated. Over the years we have managed to develop a simple step-by-step system to get you from "What are case interviews like at BCG?" to "I am confident I can get a job at BCG".

We have helped more than 30,000 candidates prepare for their consulting interviews, and in this guide, we have summarised the most important things you need to know to prepare for your BCG case interviews. 

Part 1: BCG interview process and skills tested  

The first step towards getting an offer at BCG is understanding the process you will have to go through and the skills BCG will be testing you on.

BCG recruiting process: 4 tools used

1.1 Three steps to get an offer

Let's first step through the different recruitment stages at BCG. In most countries this process entails 3 steps:

BCG uses 4 tools to assess candidates during its first and second round interviews:

You will get a combination of Fit / PEI questions and case interview questions in ALL your interview rounds. Your interviewer will typically ask you a one or two Fit / PEI questions (~10mins) and then move on to a case interview (~30 to 40mins). We will cover the type of Fit / PEI questions and case interviews you can expect at BCG in details below.

In addition to fit and case questions, BCG also uses the BCG Potential Test as well as a Written case. 

The BCG Potential Test is typically used in FIRST ROUND interviews. There are two versions of the test. A computer based one which includes 23 questions to be answered in 45mins. And a paper based one which includes 53 questions to be answered in 50mins.

The BCG Potential Test is frequently used by the firm but not systematically. Since we started helping candidates with the test in 2015 we have seen students taking the test in the US, Europe (UK, France, Germany, Italy, etc.) and also Asia. You can read more about the test here.

BCG also sometimes uses a written case in SECOND ROUND interviews. So far we have only heard of this being used in the US. For this written case, you will be given a set of documents, which you will use to answer case questions. You will then have 2 hours to answer these questions in the form of a 3 to 5 slide presentation, which you will have 15mins to present to your interviewer.

In a recent interview, BCG revealed they were hiring about 1,000 employees per year. As you probably know the competition for these spots is fierce. The acceptance rate at McKinsey is around 1% according to the firm's Managing Director. And we suspect that the intensity of the competition is similar at BCG.

This probably sounds intimidating. But the good news is that in our experience, it can actually become pretty straightforward to succeed at a BCG interview if you prepare in the right way. 

1.2 Timeline to get an offer at BCG

When preparing for your BCG case interview, it can be difficult to know when to expect each stage of the interview process. To help illustrate a typical timeline, we've created the below overview of BCG's recruitment schedule. As a rule of thumb, you can expect the whole process to take 4 to 6 weeks.

Please note: this is meant to give you a general overview, and may not reflect your specific interview timeline. Actual interview timelines depend on a number of factors (e.g. Experienced hire vs. University hire). The below is based off of the expected recruitment timelines at the University of Chicago (an MBB target school). You can find the original document from the University of Chicago here

BCG case interview timeline

1.3 Core skills to demonstrate to get an offer at BCG

There are three core skills BCG will test you on during their case interviews:

  • Problem solving and maths
  • Creativity and business sense
  • Communication

First, BCG will have already started testing your problem solving and maths skills with their BCG Potential Test. But virtually all the case interviews you get will continue testing this skill. In practice, this means that you need to be able to do mental maths quickly and accurately. And to solve the problem you are given in a clear and structured way.

Then, BCG will also test your creativity and business sense. As a consultant, you will often have to generate innovative ideas to solve the business problem at hand which is why consulting firms want to test you on this. For example, your interviewer could ask you to generate ideas on how to attract more visitors to an amusement park, or how to decrease the park’s costs.

Finally, your communication skills will also be tested throughout the process. Cracking the case is only half the battle. The other half is doing it in a way that is structured and easy to understand for your interviewer. In practice, that means you should follow a step by step approach to solve every question you get.

To get a feel for what strong and structured communication sounds like, take a look at the BCG & Bain live case interview extract included in part two below.

Part 2: BCG case questions 

Now that you know what to expect in your BCG interviews, let's dive into the different parts you need to prepare for. We'll begin with case questions. The video below will give you a good overview of what BCG case interviews are like:

2.1 BCG case interview structure

Case interviews can be challenging, but the good news is that they can be broken down into seven different types of questions. If you can consistently solve each type of question, you will be able to consistently crack cases, which will help you get an offer at BCG. Learning to solve each type of question should therefore be your objective as you prepare for interviews.

BCG case questions: 7 different types to know about

Let’s take a look at each of them one by one:

  • Situation
  • Framework development
  • Framework exploration
  • Quant question – Data provided
  • Quant question – No data provided
  • Creativity question
  • Recommendation

You can read more about case interviews and how to prepare for them, in our ultimate case interview guide. The next few paragraphs will summarise the seven types of case questions mentioned above.

In every case, the first thing your interviewer will do is lay out the problem faced by the featured company. Then, they will ask you the areas you would look at to solve the company's problem. This is called the framework development question. If you would like to learn more about frameworks you should take a look at this blog post.

In certain types of business problems, you will then have to explore the framework to find the root-cause of an issue. This is the framework exploration question. For instance, if the objective of the case is to find why the company profits are going down, you will have to EXPLORE the framework and test different hypotheses. For example, profits could be going down because of revenues, costs, or both. 

Note that you will not always get a framework exploration question. Your interviewer will sometimes jump straight into quantitative questions. For instance, you may be asked to analyse which countries Starbucks should go into next. The problem is not about finding the root-cause of an issue, and exploring your framework therefore makes less sense.

Next, you will usually have to solve a quantitative question to further understand the business problem at hand. There are essentially two types of quantitative questions in case interviews. Questions where the interviewer provides you with graphs and tables. And questions where no data is provided and you have to make assumptions by yourself.

In addition, your interviewer will also often ask a creativity question. These are typically open-ended questions such as “what can the company do to justify increasing its product prices?” These questions aim at assessing your capacity to generate qualitative ideas to solve the problem your client is facing.

Finally, at the end of the case your interviewer will ask you a recommendation question. This will test your ability to summarise your thoughts on your clients’ situation and what they should do as a result.

The order and format of these questions may vary slightly between your different interviews. But you will invariably come across them at some point during your cases and should be ready for them. 

2.2 BCG Interview questions

A great way to learn the 7 different types of case questions, is to practice with cases provided directly by BCG. On their website, BCG has a case library where you can learn the same kind of scenarios you might encounter on your BCG case interview. 

Check out BCG's case library here, and try to map the questions in each case to the 7 different question types we have listed above. 

As you're practicing, try to replicate real-life conditions as much as possible. In the next few sections, we'll highlight a few tips that will help you perform on the candidate-led cases BCG uses. If you want even more tips, check out our larger post about case interview tips.

2.3 Tip #1: Make a hypothesis at the right time

One of the questions candidates often ask us when preparing for case interviews is: “Should I use a hypothesis? And if so, when should I use one?” Some coaches such as Victor Cheng from caseinterview.com use a hypothesis all the time. But doing this in practice can feel quite artificial during your case interviews.

For instance, if you are trying to decide what type of new beverage Coca-Cola should launch next year, using a hypothesis is possible but does not add a lot of value. You could start by saying something like: “I’m going to hypothesise that Coca-Cola should launch a new diet orange juice next year because customers are more and more health conscious”.

But, this would be nothing more than a wild guess at the beginning of a case. This is why a lot of candidates are uncomfortable using a hypothesis driven approach. In real life, the main situation when consultants use a hypothesis is when they are looking for the root-cause of an issue.

For instance, when they are trying to understand why the profitability of a company has decreased. The root-cause could be many things: lower price, lower volume, higher variable costs, etc. Using a hypothesis in these cases is actually very helpful because it enables consultants to stay really focused and to methodically test all the potential sources until the real issue is identified.

Our recommendation is therefore to do the same in your cases and to only use hypotheses in framework exploration questions where you are looking for the root-cause of an issue.

2.4 Tip #2: Lead the case

Another important feature of candidate-led cases at BCG is that the interviewer will want you to take lead on the case. This is why BCG cases are often called “candidate-led” cases. After you present your framework to your interviewer they won’t tell you what to do. They will expect you to take the lead and to suggest a next step.

This can be surprising at first, if not intimidating. However, there is a very simple way of dealing with this. Every time you answer one of your interviewer’s questions you should essentially suggest a next step.

For instance, if you have just presented your framework, you should say something like: “To summarise, I think we should look into revenues and costs to solve this problem. As a next step, my suggestion is to analyse revenues in more detail. I understand revenues have been going down. Would we happen to have any details on how fast that decrease has happened? And how it has impacted the company’s different products?”

By suggesting a next step and asking for more information, you are taking a lead on the case. Interviewers are instructed to be well-intentioned. If you get stuck or are not on the right track they will nudge you in a different direction.

2.5 Tip #3: Only make data assumptions if you have to

Another important aspect of candidate-led interviews at BCG is that they will require you to make more data assumptions than interviewer-led cases at McKinsey. This is because BCG tends to use more quantitative questions without giving you any data, but McKinsey is less likely to do that.

One question we often get from candidates is: “When should I make a data assumption vs. directly ask the interviewer for the data?” The answer to this is actually very straight forward. You should always ask for the data first. And only if your interviewer tells you the data is not available should you make data assumptions.

A lot of candidates worry about asking for data that’s not available. But in reality that’s actually perfectly fine. It’s really hard for you to guess which data points the interviewer has or doesn’t have. As a result, if you ask for a data point that your interviewer would like you to estimate, they will simply tell you that they don't have the data available.

2.6 Tip #4: Follow the BCG case interview dress code

Another question that candidates often wonder about before their first case interview with BCG, is how they should dress. There are a few things that you should keep in mind when it comes to the dress code. We've summarised some highlights below, and you can also read more in our article on the consulting interview dress code for men and women.

First, follow recruiter instructions. If your HR contact tells you to dress business professional, do it. If they say business casual, dress accordingly. If they haven't specified the dress code, you should feel free to ask your recruiter. They get these questions all the time and will be happy to answer.

Second, don't try to impress interviewers with how you dress. You should dress conservatively for your BCG interview. This may surprise you, but your goal for attire should be to NOT stand-out. Your BCG interviewers are far more interested in your analytical and communication skills than your wardrobe. 

At the end of the day, probably the only reason an interviewer would remember your attire is if you dressed badly. So don't take unnecessary risks, and avoid wearing anything flashy or attention-grabbing, like big jewelry and cuff links. Below is the typical attire for BCG case interviews, for both men and women.

Typical dress code for men:

  • Suit in a neutral color (e.g. black, grey)
  • Button-up shirt in a simple style and color (e.g. white, light blue)
  • Tie without flashy patterns
  • Black or brown dress shoes that go with your suit

Typical dress code for women:

  • Conservative dress or pantsuit in simple colors (nothing shiny or bright)
  • If wearing a pantsuit with a blouse, white is standard for the blouse
  • No large or loud jewelry, small and simple items are appropriate
  • Shoes should be conservative and comfortable 

Use your judgment in choosing your interview attire. Asking your HR contact for the dress code is helpful, especially for events or mixers where it's less clear. When in doubt, choose clothes that are professional and conservative. It's better to go unnoticed than for interviewers to be distracted by your wardrobe choices.

Next, we'll turn our attention to the fit and PEI questions that BCG uses.

Part 3: BCG fit and PEI questions

In addition to case interviews you will also get behavioural interview questions at BCG. There are two types of behavioural questions you should be aware of:

  • Fit questions (~66% of questions). These are questions such as "Why consulting?" or "Why BCG?" They aim to assess whether you are good fit for the firm.
  • Personal Experience Interview (PEI) questions (~34% of questions). These are questions such as "Tell me about a time when you took a leadership role" or "Tell me about a time when you have to deal with ambiguity." They aim to assess if you have the soft skills required to be a good consultant.

Let's step through the top 5 fit questions first and then the top 5 PEI questions. The percentages we are sharing below come from analysing data for BCG interviews on Glassdoor.com.

Fit and PEI questions asked at BCG

3.1 Top 5 fit questions asked by BCG

Let's step through the top 5 fit questions you will come across in the behavioural part of your interview with BCG. Note that the percentages for the top fit questions discussed here add up to 100%. But as mentioned above, altogether fit questions just make 2/3rds (~66%) of behavioural questions asked by BCG interviewers.

So here is the top 5:

  1. Why consulting? (23% of fit questions)
  2. Why BCG? (21% of fit questions)
  3. Walk me through your resume (7% of fit questions)
  4. Tell me something that's not on your resume (7% of fit questions)
  5. What's your career plan / 5-year plan? (6% of fit questions)
  6. Other (29% of fit questions)

We've covered in detail what you should answer to the "Why consulting?" and "Why BCG?" questions in the past. Questions 2 to 4 are also often asked at other firms and we have covered them in our guide on consulting interview behavioural questions.

But one question that seems to come relatively frequently at BCG but not at other firms is "What's your career plan?" or "Where do you see yourself in 5 years?" This question is a little bit of a trap. Many students candidly reply that they will probably do consulting for 2 or 3 years and then do something else. This is a BIG mistake.

BCG wants to hire junior consultants who are committed to the job and want to make partner. The firm will invest a lot into developing you when you join. And they'll want you to stay as long as possible.

A better answer to the question is something like: "I've carefully thought about whether I want to do consulting or not and decided this was the best option for me. In 5 years I would like to still be a consultant and to start managing teams. I am also keen to specialise in one or two industries at some point. Today I'm interested in retail and technology, but that might change as I try different industries while working at BCG."

3.2 Top 5 PEI questions asked by BCG

Let's now turn our attention to PEI questions asked at BCG. These competency-based questions are actually very similar to the McKinsey Personal Experience Interview questions. They are focused on testing the specific skills that BCG looks for such as: problem-solving, leadership, focus on impact and passion.

The exact way in which your interviewer will ask the question will vary, but it will usually start with "Tell me about a time when..." and then some variation of the topics below. Here is the top 5 for BCG:

  1. Managing a team conflict / situation (21% of PEI questions)
  2. Leading others (17% of PEI questions)
  3. Overcoming challenges (12% of PEI questions)
  4. Managing a personal conflict (10% of PEI questions)
  5. Influencing others (9% of PEI questions)
  6. Other (31% of PEI questions) 

The top 5 questions here are also common at McKinsey. If you would like to learn more about these types of questions and how to answer them you should read this article on how to impress your interviewer in personal experience interview questions.

In addition, BCG also asks other PEI question that don't seem to be used by McKinsey nor Bain, according to the analysis we did using Glassdoor.com data. In particular, this includes the following two questions:

  • Tell me about your biggest individual / team failure (9% of PEI questions)
  • Tell me about a time when you had to deal with ambiguity (7% of PEI questions)

You should prioritise the top 5 questions above in your preparation. But if you have time, or if you make it to the second round of interviews, it will also be worth preparing answers to these two additional questions.

Part 4: BCG case interview preparation plan

So what's the best way to prepare for your BCG case interviews? In our experience, the following 4-step approach yields really good results.

BCG case interview preparation plan

  • First, develop fast and reliable maths skills
  • Second, master a consistent method to crack cases
  • Third, practice case interviews
  • Fourth, work on fit / PEI interview questions

For full disclosure, this is the approach we take in our BCG & Bain Case Interview Training Programme and more than 80% of people who have used it so far ended up getting an offer. But even if you don't end up using these programmes, we still encourage you to take this four-step approach. Trust us, it really works!

Let's step through each stage of the preparation plan to give you more details about what you should do in each.

4.1 Become really confident at maths

BCG will test your maths skills in the BCG Potential Test but also during the interview. It is therefore difficult to succeed at these interviews without being confident in maths. The firm makes it clear on their website that you should expect maths questions during your interview (see here).

However, it is extremely common to have rusty maths skills when you start preparing. In our experience, candidates who end up getting a job in consulting take some time at the beginning of their preparation to brush up their maths and regain their confidence.

We find that making this initial investment is really worth it. This is the first step candidates take when they enroll in our BCG case interview training programme. We have also put together a few maths tips here which you might find helpful to get started.

4.2 Develop a consistent method to crack cases

One of the challenges of interviewing with companies like BCG is that you will have to do five to ten interviews before getting an offer. For each of these interviews you will get a case that you need to crack. You therefore need to learn a CONSISTENT way of cracking cases.

As mentioned previously, the good news is that candidate-led cases can be broken down into very specific types of questions: situation, framework development, framework exploration, quant questions with and without data, creativity questions and recommendation questions. If you find an approach to consistently crack each type of question within a case, then that means you will be able to consistently crack the case overall.

At IGotAnOffer, we were frustrated with the lack of a consistent approach to solve case questions when we were preparing for interviews. This is why we created a step-by-step method to solve cases that we teach in our BCG case interview training programme.

Developing a consistent step-by-step approach will enable you to develop HABITS. And having developed these habits during your preparation will enable you to focus on the case at hand and to consistently crack the questions interviewers throw at you.

4.3 Practice cases out loud

One important aspect of your preparation is also trying to reproduce the conditions of a real interview. A great way to achieve this is to do case interviews with friends or with former consultants who do coaching interviews.

However, this isn’t always possible and you will have to do some cases by yourself. In these situations, we would really encourage you to practice out loud. This means you should both play the role of the candidate and of the interviewer. In practice, that means you should ask questions and answer them out loud in the same way two people would do in an interview.

This will feel odd at first. But trust us; it actually makes a huge difference in your preparation. This is because THINKING about the right answer is only half the battle in case interviews. The second half is COMMUNICATING your answer in a clear and structured way.

If you don’t practice out loud, you are only practicing half of the skills required to be successful. We really encourage you to give it a go as in our experience candidates who use this approach are much more likely to get an offer.

4.4 Learn from every mistake you make

Finally, you should really focus your preparation on quality rather than on quantity. Sure, there is a minimum number of hours you need to put in to develop good case interview habits – probably ~30h+. However, in our experience, successful candidates find it more valuable to do 20 cases and to learn as much as possible from them, than to do 40 cases and to not learn much at all.

The best way to achieve this is to keep a notebook where you write down your mistakes at the end of each case. You should go back to that notebook on a regular basis and remind yourself of the things you have learned. This will enable you to avoid repeating the same mistakes twice and to make sure you actually progress as you do more and more cases.

A good way to check that you have actually progressed is to redo some of the cases that you did at the beginning of your preparation after a while. For instance, after you have done case #20, you could go back to case #1 to make sure you are not repeating the same mistakes. This way you can be sure that you are on the right track and actually making progress.

Additional resources

If you would like to fast track your case interview preparation and maximise your chances of getting an offer at BCG, come and train with us. More than 80% of the candidates training with our programmes end up getting an offer at their target firm. We know this because we give half of their money back to people who don't.

BCG & Bain Case Interview Training Programme

BCG & Bain case interview training programme

Any questions about BCG case interviews?

If you have any questions about case interviews, do not hesitate to ask them below and we will be more than happy to answer them. All questions are good questions, so go ahead!

The IGotAnOffer team