How much time does someone need to prepare for McKinsey/Bain interviews?

3 weeks of 1 hour a day is  too little unless you are in the small minority of people that have a very strong natural affinity for casing. If you only have 3 weeks before an MBB interview, see if you can ask the recruiter to delay. Most people take 6 weeks+ to get interview ready.

I would strongly suggest that you do a combination of solo preparation (to understand core concepts and do drills), peer prep (for case interview reps), and coaching (to quickly accelerate your progress).

Obviously I am biased, but coaching is by far the highest ROI time spent, since good coaches have actually interviewed MBB candidates and know how the process works back-to-front

Hi there! 

While every candidate is different, I thought I'd share some (hopefully helpful) perspective/ general benchmarks that I've personally experienced in preparing for interviews at top management consulting firms. 

Here's what to expect if you're still more of a beginner at case interview prep (if you're already more experienced, you can certainly adjust accordingly from here):

• Recommended prep time: beginners typically need several weeks of focused preparation, often around 6-8 weeks or ~60+ hours, to be ready for consulting case interviews at MBB (McKinsey, Bain, BCG) and other top firms. I've seen many successful candidates invest even more time than that (sometimes 100+ hours over 2-3 months) to reach a high proficiency level. As a part of that time, expect to practice roughly 30-50 mock cases, which is a key part of prep since each case practiced builds skills and confidence that is hugely valuable for real interviews. 

  • Key takeaway: aim for at least ~60+ hours and 30-50 mock cases to prepare for MBB interviews.

     

• Self-study alone is not sufficient. Reading case books, learning frameworks, and going through cases on your own is valuable for building fundamentals, but nothing replaces live mock interviews with partners or coaches. Mock interviews train you to solve problems out loud, under time pressure, and with interactive feedback, which mirrors what actual interviews test. And sure, while only part of a mock session is spent solving a case, the rest (feedback, discussion, role reversal), if done well and efficiently, is critical learning time that sharply improves your performance. For example, I recommend spending ~15–20 minutes debriefing each 30–40 minute practice case to maximize learning.

  • Key takeaway: use self-study to learn basics and drill skills, but prioritize mock cases (30-50 of them) to develop interview-ready skills.

     

• 3 weeks @ 1 hour per day (i.e., ~21 hours) is likely too little for MBB interviews. Top consulting firms have a high bar; most successful candidates prepare ~60 hours (often more) for case interviews, and typically only very exceptional candidates with strong business intuition or prior experience might pull off an offer with such limited prep. That said, if you literally only have ~3 weeks to prep, try to increase your daily hours and focus intensely on high-quality practice; if I'm being brutally honest, you should treat that limited time as an emergency, full-on sprint. Focus on quality over quantity: use resources that teach you the core skills quickly (for instance, an accelerated case course like the ones available on PrepLounge). Then dive into mock interviews immediately – perhaps start with a friend for comfort, then quickly move to practicing with other candidates or coaches who can challenge you. Identify your biggest weakness early (maybe your math, or structuring, or communication) and concentrate on fixing that, rather than trying to cover every possible case type superficially. It’s also wise to temper expectations: with only 3 weeks, you might not reach the polish of someone who prepared for 2 months, but you can still make significant improvement if you’re disciplined. And if you do secure more time (e.g. interview gets postponed), use it fully.

  • Key takeaway: ~21 hours is generally too little for an average beginner aiming for MBB; aim for ~60 hours (or more) if you can.

     

Hope that helps! Feel free to reach out with questions or concerns; I'd be happy to setup a free intro call to help you craft a custom plan for success with whatever prep time you have available.


Best,
David

Hi there, 

Preparing on your own would not be enough. In the real interview you have to face an individual who you most likely have never met before - you need to be trained in such setting, and be able to handle the interaction / engagement with the interviewer. It is very different to it in real vs. imagining it in your head. Consider getting a coach if you find the peer mock interviews are not giving you the best use of time (who you mock with makes a bit difference). 

3 weeks of 1 hour per day (21 hours in in total) is too little prep. For a candidate to get well prepared, the minimum # of practices would be 25-30 mock cases. And to make each practice really count, it is not only the 1 hour you spend doing the mock and discussing the feedback - candidate should do multiple rounds of review / reflection afterwards to internalize the learning. From my experience, candidate should spend 3x the time on each case practiced to get the max value from the practice. In addition, besides just mock case, candidate should also spend time to hone communication skills, get more prepared with some business, finance and industry fundamentals. So in total, it definitely requires more than 21 hours. 

Best,

Emily

Hi there,

First of all, congratulations on the (presumed) invitations from McKinsey and Bain!

I would be happy to share my thoughts on your questions:

• First of all, since you are certainly right to state that peer practice is not the most efficient way, you have two more options: friends and family, and an experienced coach like myself. In any case, I would strongly advise you to stay away from practicing on your own, as it is not efficient and doesn't simulate the actual interview situation properly.
• Moreover, instead of thinking about the bare minimum required to succeed in the interviews, I would strongly advise you to shift your mindset to ensuring that you eliminate any reason to reject you that is in your control as soon as possible. There are still enough reasons to reject candidates that are out of their control.

You can find more on this topic here: How to succeed in the final interview round.

If you would like a more detailed discussion on how to best prepare your application files, for your upcoming pre-interview assessments and/or interviews, please don't hesitate to contact me directly.

Best,

Hagen