Bain case interview - How to prepare (2024)

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 Bain is that the interviewer will want you to take lead on the case. This is why Bain 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 simply 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 Bain is that they will require you to make more data assumptions than interviewer-led cases at McKinsey. This is because Bain 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 is not available, but in reality that’s perfectly fine. It would be nearly impossible 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 Bain case interview dress code

Another question that candidates often wonder about before their first case interview with Bain, is "what should I wear for my Bain interview?". 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 Bain interview. This may surprise you, but your goal for attire should be to NOT stand-out. Your Bain 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 Bain 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 Bain uses.

Part 3: Bain fit and PEI questions

Bain interviewers will also ask you behavioural questions during your interviews. You will come across two main types of questions:

• Fit questions (~90% of questions) such as "Why consulting?" or "Why Bain?" These questions are used to assess if you are a good FIT for Bain.
• Personal Experience Interview (PEI) questions (~10% of questions) such as "Tell me about a time when you lead others" or "Tell me about a time when you managed a team conflict." These questions are asked to assess your SOFT SKILLS.

All firms ask a slightly different mix of PEI and fit questions. We have analysed data from Glassdoor.com for Bain and have summarised the top 5 fit questions asked by the firm and the top 5 PEI questions. Let's go through each list one by one.

3.1 Top 5 fit questions asked by Bain

Let's start with fit questions. Note that the percentages for the top fit questions discussed below add up to 100%. But as mentioned above, fit questions account for ~90% of behavioural questions asked by Bain interviewers, with PEI questions making up the remaining 10%.

So here is the top 5 fit questions:

1. Why Bain? (33% of fit questions)
2. Why consulting? (25% of fit questions)
3. Introduce yourself / Walk me through your resume (20% of fit questions)
4. Tell me about X on your resume (5% of fit questions)
5. Why choose location X? (4% of fit questions)
6. Other (13% of fit questions)

Fit questions at Bain are extremely predictable. The top 3 account for ~80% of all questions. We've extensively discussed how to answer the "Why Bain?" and "Why consulting?" questions in previous posts. Questions 3 and 4 are also frequent questions and you might want to read our article 4 ways to answer “Walk me through your resume”.

But one question that seems to be more frequent at Bain than at other firms is "Why choose location X?" This question is often asked as a follow up to the "Why Bain?" question.

Bain interviewers really want to make sure that you have carefully thought about whether consulting and Bain are a good fit for you. And a big part of your experience as a consultant will depend on the office you are joining.

If you are joining the Houston office, you'll do a lot of oil and gas work. If you are joining the New York office, you'll work in finance and media a lot. Your interviewer wants to make sure that you have done some research and are aware of these differences.

This question is also an indirect way for your interviewer to make the conversation a bit more personal. If you have family in New York or have always wanted to work there because you love the city, now is your opportunity to say it!

Overall, our recommendation for answering the "Why choose location X?" question is to give a mix of work reasons and personal reasons. For instance, you could say something like: "I'm excited to join the New York office for two reasons. First, I'm interested in finance and media and I understand this specific office does a lot of work in these areas. And second, I have family in New York and I've decided it would be a good place for me to start my career."

3.2 Top 5 PEI questions asked by Bain

Let's now briefly turn our attention to PEI questions asked at Bain. These questions only account for about ~10% of behavioural questions asked by the firm. You should only start preparing for these once you are very comfortable with fit questions which are much more frequent (~90% of behavioural questions).

The PEI questions used at Bain are similar to McKinsey Personal Experience Interview questions. They are competency-based questions designed to test the skills Bain looks for such as leadership, impact, and passion. PEI questions are easy to identify because they almost always start with "Tell me about a time when ..." and then some variation of the topics listed below. Here are the top 5 for Bain:

1. Leading others (50% of PEI questions)
2. Managing a team conflict/situation (20% of PEI questions)
3. Managing a personal conflict (10% of PEI questions)
4. Overcoming challenges (5% of PEI questions)
5. Influencing others (5% of PEI questions)
6. Other (10% of PEI questions)

We've written extensively about how to answer PEI questions in the past. Our recommendation is to prepare in advance and to use a pre-defined structure that will ensure you cover all the aspects you interviewer expects. You can read more about this approach here. In addition, you can also find Bain's own tips on the personal experience interview here.

Part 4: Bain case interview preparation plan

So what's the best way to prepare for your Bain interviews?

Let's go through the most important things you need to do to make sure you're fully prepared and to maximise your chances of landing that job offer.

4.1 Become really confident at maths

You don't have to have a perfect GPA or GMAT score to succeed at case interview maths. However, during your Bain interviews, you will be expected to quickly perform accurate mental maths. 

In order to do this, it’s essential to know the formulas for common metrics, like return on investment or breakeven point. And it’s also helpful to know a few maths shortcuts to help you solve problems more quickly. To learn more about these topics, check out our free guide to case interview maths. 

In our experience, the most successful applicants start their interview preparation by practising maths skills, so make sure you prioritise this step.  

4.2 Develop a consistent method to crack cases

One of the biggest challenges of interviewing with Bain is solving cases that you’ve never seen before. Each case can be difficult, and you’ll have to perform well across multiple case interviews in order to get an offer.

As a result, it’s critical for you to have a consistent approach for solving cases. Bain uses candidate-led case interviews, which can be broken down into the following types of questions:

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

If you can crack each type of question (within a case), then you can crack the overall case.

4.3. Practise with peers

Once you're in command of the subject matter, you'll want to start practising cases. But by yourself, you can’t simulate thinking on your feet or the pressure of performing in front of a stranger. Plus, there are no unexpected follow-up questions and no feedback. 

If you have friends or peers who can do mock interviews with you, that's an option worth trying. It’s free, but be warned, you may come up against the following problems:

• It’s hard to know if the feedback you get is accurate
• They’re unlikely to have insider knowledge of interviews at your target company
• On peer platforms, people often waste your time by not showing up

For those reasons, many candidates skip peer mock interviews and go straight to mock interviews with an expert. 

4.4 Practise with experienced case interviewers

In our experience, practising real interviews with experts who can give you company-specific feedback makes a huge difference.

Find a Bain consulting interview coach so you can:

• Test yourself under real interview conditions
• Get accurate feedback from a real expert
• Build your confidence
• Get company-specific insights
• Learn how to tell the right stories, better.
• Save time by focusing your preparation

Landing a job at a top consulting company often results in a $50,000 per year or more increase in total compensation. In our experience, three or four coaching sessions worth ~$500 make a significant difference in your ability to land the job. That’s an ROI of 100x!