by Brian DeChesare Comments (164)

10 Investment Banking Internship “Don’t”‘s: How Not To Screw Up

10 Investment Banking Internship

I’ve given some internship tips in the form of a summer intern success guide and an avid reader gave some tips from his firsthand experience, but it’s often easier to give advice on what not to do (as with fashion).

Without further ado, here are the top 10 summer intern gaffs I’ve observed, both at my office and from friends’ stories.

This list applies to both Summer Analysts and Summer Associates – your role is the same, except Associates will get a bit more responsibility.

1. Argue with me over something financial/modeling-related

I see this more with Summer Associates than with Summer Analysts. Look, I understand you learned a lot about finance and accounting in business school and know all sorts of concepts that I don’t.

I also understand that you have several years (or more) of work experience and know a thing or two about how to perform well in a corporate environment.

But if you haven’t done investment banking before, you don’t know how we do things and you probably don’t realize the difference between what you learned in school and how financial work is done in the real world (corners are often cut).

Last year a Summer Associate spent 30 minutes arguing with me over how to calculate foregone interest on cash in a merger model and I said, “Yes, your way is correct but it makes a difference of less than 0.01 and would take time to change, which is why we don’t do it.”

So don’t even think of starting a debate.

2. Call me late on a Friday or Saturday night with non-urgent questions

Not that I’m bitter or anything, but this one always happens to me, and usually interns are at fault. If I’m out on a Friday night, I don’t want to be bothered with questions on Excel shortcuts or anything else that can wait until the next day (or next week).

Sure, ask questions when I’m around, but don’t go out of your way to contact me at odd hours unless it’s truly urgent.

This also brings up another point: within the Analysts at a bank, you generally want to ask questions of 1st Years first before going to 2nd/3rd Years.

Especially if the 2nd/3rd Year in question is leaving shortly.

3. Dress better than me, especially on your first day

I’m not going to lie; I tend to be a minimalist when it comes to clothing, especially compared to some other bankers out there.

Although it’s actually pretty easy to dress better than me, you still don’t want to come in wearing a $5,000 suit and gold watch on your first day.

Every office has a different culture, but most places will think this is really odd… it’s much better to wear standard business casual attire that doesn’t raise eyebrows.

Save your good clothes for when you start full-time or get a promotion.

4. Be overly enthusiastic – it’s just creepy

Look, attitude is very important as a Summer Intern… you want to be eager to learn and help Analysts save time on projects.

But there’s such a thing as being too enthusiastic as well. It would be pretty weird if I gave you an assignment that required you to pull an all-nighter and you were happy about it.

Even if you are somehow happy to pull an all-nighter, it comes across as fake and people will assume you’re lying.

5. Fail to invite me out drinking or to social events

The best part of having summer interns is that some are actually cool to hang out with. My life as an Analyst is usually pretty mundane: Excel, PowerPoint, research, rinse, wash and repeat. Having summer interns provides a great break and a chance to get to know new people.

Usually firms spend a lot of money on summer recruiting events and such, so if there’s an event/party/outing and you don’t let me know about it, I’m going to be annoyed.

Forget about just saving me time, enhance my lifestyle and you’re golden.

6. Say you’re too busy to get coffee

Similar to #5 above but from the opposite side. As Analysts, Starbucks is our lifeblood. So when we go out for coffee for 5-10 minutes and invite you to come along and you say you’re too busy, a couple things come to mind:

1) I know you’re probably lying because I give you work and determine how busy you are.

2) I think you don’t want to hang out with us and are not going to fit into our group.

Unless you have a true fire drill and really need to send something important out (unlikely as an intern), you have time to grab coffee.

7. Pretend that your internship is longer than 8-10 weeks

Personally, I am extremely nice to summer interns and rarely give them annoying work unless I’m so busy that I can’t finish everything myself.

Some Analysts have a different philosophy and as soon as they get summer interns, they turn into “Managing Analysts” and start giving all their underlings the dumbest work imaginable.

It’s unfortunate if you end up in this situation, but also keep in mind that your internship only lasts a matter of weeks – a lot less than 2-3 years. So no matter how bad you have it, it’s not worth complaining about because it’s over and done with quickly.

8. Hook up with other interns/analysts/secretaries

This one may cause some controversy, but I think it’s a really bad idea to get involved romantically with anyone else at your office, especially as an intern.

Friends have done this before but typically it’s at the end of the internship; otherwise there’s just too much risk of bad things happening and offers getting revoked.

Don’t think you can keep anything like this a “secret” – there are no secrets in an investment banking office.

One time when I was interviewing for buyside jobs, somehow not only my entire office but also multiple other offices found out and asked me how it went afterward.

If something as small as that becomes the talk of the Analyst class, you can guess how quickly news of a rendezvous with your MD’s secretary will spread.

9. Show up to work with a hangover

Control yourself when drinking and going out with other interns/Analysts. If you do anything really stupid (e.g. getting violent with an MD while drunk), your chances of getting an offer are pretty much 0.

Similarly if you show up to work with a hangover (or are still drunk), people will notice.

If you ever have to think about whether or not to do something, you shouldn’t do it.

10. Badmouth the firm/office to anyone else

This one actually came up this past year. One of our top summer analysts did very well and got an offer, but decided banking was not for him and went into another field.

That’s perfectly fine and I respected his decision. But then I find out he was going around to others interviewing at my office and telling them not to work there and such just because he personally didn’t like it.

The world of finance is very small and if someone knows something, chances are everyone else knows it too.

Openly badmouthing a firm or office to others is just unprofessional and pretty much ensures you’ll have no chance of working there in the future (I know, I know, you don’t want to, but still…).

M&I - Brian

About the Author

Brian DeChesare is the Founder of Mergers & Inquisitions and Breaking Into Wall Street. In his spare time, he enjoys memorizing obscure Excel functions, editing resumes, obsessing over TV shows, traveling like a drug dealer, and defeating Sauron.

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Read below or Add a comment

  1. Dear Brian and the M&I team, I am a 17 year old student studying in abroad in Concord College in the UK, I have a great passion towards stocks and how the market fluctuates, in particular, the investment banking sector. I was wondering whether it was possible to apply for a summer internship in your firm in Hong Kong as I would really enjoy working in your firm in the near future and a head start would be beneficial.

  2. badmouthing is also a “don’t” because it can prevent you from receiving good recommendations

  3. Dear Bryan;

    I feel really happy of having the chance to read your priceless articles and typs about what is to being in the finance industry.

    I am a graduated in business management from Spanish university. I am 26 with experience in Human resources in Africa and Emerging Markets as an expatriate. However; since half a year ago; I am looking for a career change; to the finance field. I do not care about investment banking; just want to develop an international finance career: break into the industry. So; I am preparing for the CFA level 1 exam; planning to move to Australia to both masterize my English and study a master regarding the field.
    From your experience; Do you think this plan is suitable? How long do you think it could take me to break into the field?
    Which adviece could you give from your experience?

    All comments will be higly appreciated.

    Thanks for your time.

    1. Yes, I think your plan is reasonable but I think you need a more specific idea of what you want to do first. It might take anywhere from 1-3 years to move into a completely new field, but it’s tough for me to explain what to do or to recommend certain actions without knowing where you want to work (e.g., equity research? Asset management? Corporate finance? Trading?).

      1. Dear Brian;

        First of all thanks a lot for your answer. Receiving an answer from someone someone with experience in the field means a lot to me.
        Please let me briefly draw the picture of universities and the finance sector in Spain.
        Here people study mainly Business administration or Economics.( when it comes to work in The industry) Both are really theoretical and without an specialization; during the 4 or 5 year studies.
        As a result you end up without being able to differentiate between PE and IB for example.

        About me ; I will really like the most asset management or M&A . I rather prefer fundamental analysis than technical one about this I am quite sure.
        For example ; within the Level 1 curriculum I enjoy the most FRA.
        Hope you can give me a light; since here in Europe I think the career paths are not as broad as in The States.

        Thank you again. Looking forward to hearing from you.

        1. OK – again, your plan sounds plausible, but I’m not sure of the question you’re asking. I would say continue with the CFA, consider a Master’s in Finance program, and try to get an internship at a small/local asset management firm to get some experience on your CV.

  4. I have an interview at a very small boutique merchant bank on Friday. I am flying from school to nyc for a couple interviews but that is my only one in finance. I have a huge test this week so I don’t have time to buy a suit let alone get fitted. I have very nice attire and can put together a really strong outfit (nice pants, jacket, tie, shoes etc) but don’t have a suit. Do I absolutely need to wear a suit? If its important enough I’m sure I can figure out how to make it happen. For some context their recruiting is super informal and I stumbled on opportunity through cold email, had a great phone call where I felt like he was indicating that it seems like a great fit and when we were talking about my visit the conversation was also very informal. Firm is very small (under 7) but is in pretty fancy building. Any suggestions or feedback would be much appreciated.

    1. M&I - Nicole

      If you are very confident that your attire is professional, then I’d say you may not necessarily need a suit, especially if recruiting is very informal and you noticed people aren’t all in black suits. Since the firm is small, I doubt they’re too formal. However, I’d suggest that you meet up with a few friends and professors in your attire and ask them if you look professional or not. Otherwise, can you borrow a suit from a friend? This is just a backup plan. may also help you.

  5. Hi,

    I just wanted to say thanks for this articles. They are all brilliant!

    1. M&I - Nicole

      Pablo, you’re welcome. Thank you for visiting our site!

  6. Hi Brian, Thanks for the article, very interesting.

    I am an incoming penultimate year undergrad. I have been interning at a US private placement firm over the summer in Shanghai. I am studying in London, but I am quite interested in Asian market. So i am struggling between London and Shanghai, mind shed more light on this.

    -Will I stand more chance if I apply to private equity arm of an investment bank, as compared to the IBD, i.e.GS IBD VS Merchant Banking Division, I prefer starting in IBD though?


    1. M&I - Nicole

      If you want to work in Europe, London is better. In Asia, I’d choose HK over SH.

      I’d say IBD is easier and better option given training

  7. Hi Brian/Nicole,

    Not entirely related to this article, but I was wondering whether or not there is any danger of having too many internships? By internships I mean 2/3 month placements in small M&A/CorpFin boutiques (London). I am currently in my second placement, and have a third one lined up. I would like to eventually apply for FT positions in BB banks this coming recruitment cycle.

    Thanks in advance!

    1. M&I - Nicole

      I wouldn’t say danger, because having solid work experience is great! You just need to explain why you moved very well for FT roles and your future goals.

  8. Dear Brian,

    You have a great site for sure. But you do sound very cynical, and a tad grumpy.
    Having worked in the I-banking industry for over 27 years, I can safely tell you that the MDs do not give a shit about the list of things you ranted about. I feel you have a great site which gets ruined by your rants. You should be focused on the job at hand and not on whether they invite you to social events.


    1. Most of these “rants” are either sarcastic and not meant to be taken seriously, or are from a really long time ago when the style of the site was much different (or a combination of both) – this post you’re commenting on, for example, was written about 6 years ago.

      This article was also not about Managing Directors, but rather how interns act toward full-time analysts/associates. And full-time junior employees do indeed get annoyed when interns try to argue with them over trivial things. Whenever you read something on this site, please assume that it is directed at entry-to-mid-level professionals unless otherwise specified.

  9. Hello. I am an Asian sophomore majoring in Computer Science and Finance at Washington University in St. Louis. I realized that my school, due to its locational disadvantage, does not get a lot of attention from recruiters from either the east or the west coast. I’ve been carefully following networking tips and advices on this website in hopes to one day land a position at one of the BBs after graduation. Currently, I’ve managed to find a couple of non-diversity-focused sophomore internship programs at big name banks and boutiques. The deadlines for these programs are fast approaching, and I know I need to network to have even a slightest chance at getting an interview. I wanted to ask whether I should be direct about my interest in applying to these sophomore internship programs when cold-emailing my contacts. Being less aggressive and just simply expressing interest in gaining insight and advice about IB might yield more responses, but keeping in mind that my goal is to increase my chances at getting a position as a sophomore intern, wouldn’t it hurt not to actually mention the name of the programs I am interested in? In addition, do you recommend that I attach my resume in my first email or does that make me appear way too aggressive? Thanks so much for your time and help.

    1. M&I - Nicole

      Yes I think you may want to be more direct given time constraints. Chances are there aren’t too many roles for sophomore interns so I’d suggest you to approach boutiques and 2nd/3rd tier firms. I wouldn’t attach your resume. Just a brief email explaining your background will do.

  10. Hi. I am currently a first year student at UCL and I am very interested in Investment Banking. I am studying IT management for Businesses and I want to know if I have any chance to get into IB with this degree. So far, all our teachers say that this is a very good degree but I am not yet 100% sure on what I could do with it(and yes, I know that I should ask them instead of asking a stranger on the internet, but all they’ve said so far is that I can do anything with this degree-from programming, to management,etc-but “anything” is a quite vague term and IB seems pretty attractive to me). In addition, I want to ask you how many holidays do you have per year and if it’s compulsory to work that many hours everyday or if you just do extra hours and you get paid for them. How many hours are you actually supposed to work every week.
    I am looking forward for your reply and I want to thank you for the articles you write. Are VERY useful. (And I am sorry if I asked any stupid question but right now I am pretty clueless with everything related to jobs)

    1. M&I - Nicole

      You may find useful. In terms of holidays, it depends on the firm. Usually from 15-20 days or more if you’re lucky. However, you may not necessarily be able to take the days off. Work wise -80-100 hours week are pretty normal.

  11. Hi, I am currently doing an (corporate finance) internship at a boutique investment bank (kind of an associate intern having finished a couple of Master’s degrees). It’s an established boutique, but there just isn’t enough work for me to do. I have only done 4 valuations and books. The valuation, research and book of a small company don’t take that long time. I have only had small exposure to a deal that is worth over $100M. This week, I didn’t have anything to do for the whole 2 days (I normally study CFA materials on a slow day). In terms of working hours, it’s 7 days a week and between 7am and 8pm. How do I spin this to get a full-time job at a tire 1 bank?

    1. M&I - Nicole

      Talk about the work you’ve done, what you’ve learned and how you’ve made an impact. Even if it is just one deal, you can talk about your involvement and what you’ve learned. You don’t need to mention your working hours because many in banks would automatically assume your hours are long in IB. I doubt if they’ll ask you lifestyle related questions, but if they do just tell them you’re a great multitasker (list examples) and that you love burning the midnight oil (list examples – not necessarily from work). But I wouldn’t bring this topic up unless they ask.

  12. Hello,
    I am currently going to be a senior in Germany. I am wondering if you could evaluate my chances of getting into a IBD graduate program after graduation since I have no more internship opportunities.

    School : target undergraduate business school of bulge bracket banks
    GPA : 3.5/4.5 but have chance to go for 3.7-3.8 until graduation
    Internships : Startup(Operations), Venture Incubator

    I am really good in Excel and believe I can catch up all the corporate finance material for the interview. Do I have, however, a good chance of landing a spot in the graduate programme? If not, can you give me some advice how to improve my chances given my situation?

    1. M&I - Nicole

      I’d say your chances are 50/50, because you’ll be competing with people who have had IB internships. With the above being said, you have decent qualifications. I’d suggest you to network a lot by attending bank info sessions, contacting alums, and maybe cold-calling/emailing people. This will set you apart from other candidates and improve your chances if you are persistent enough. And most importantly perfect your pitch and be able to articulate why you want to do investment banking.

  13. I have been involved in real estate and became licensed at 19. Currently I go to Cuny York College aiming to get a BS in Business Admin. The school is not a heavy hitter with tons of recruiters. That being said what are some ways I can land an internship besides going through the school.

    1. M&I - Nicole

      You may have to start attending finance events organized by finance societies in NY to meet more people. Perhaps you can make some friends at NYU Stern & Columbia and see if you can attend banks’ info sessions there. Going to places where bankers frequent like gyms close to their offices, bars/clubs/lounges they hang out at will increase your chances of networking

  14. Hello,

    How often are Associates/Analysts hired without prior Finance experience? I will be graduating in May with an MBA but my school doesn’t seem to have a very strong career development program.

    Any advice/thoughts??

    Thank you!

    1. M&I - Nicole

      I don’t have the numbers. Most associates/analysts have prior finance experience. I’m sure there are some cases in which candidates are hired without any finance experience at all but I think that is not common, especially in this economy.

  15. “8. Hook up with other interns/analysts/secretaries”


    Is it alright to try this if you’re working in the office?

    1. Properly working, I mean not as an intern.

    2. M&I - Nicole

      Haha, it depends on how you handle it and the situation. I don’t usually suggest “shxxting” where you eat, but it happens and couples do meet through the office

  16. I must admit I’m not too sure if the financial world is what I want to get involved in. I’m a first year mathematics student and I am always interested to know where my qualifications could take me. This may seem like a basic question but in your firm’s opinion how do you make money?

  17. Hi,
    I am currently a rising sophomore at the University of Michigan. I applied for the B-school there and unfortunately, did not get a spot. I plan on majoring in Economics. What are the chances of a Econ major getting an internship at an investment bank for the summer between Sophomore year and Junior? Also, the Ross School of Business allows me to apply again as a sophomore, however, this would require me to stay an extra year for undergrad. Would you recommend me to stay an extra year for undergrad, but graduate with a degree in Business Administration, or just to major in Econ and graduate on schedule? This summer, I am interning at the NY State Banking. Do you think this would be a valuable internship as a segue to I banking?

    1. It is tough for sophomore summer if you’re not in the business school there. I would recommend staying an extra year if you can get into the business school because it really does make a big difference for internships (from what I understand of recruiting there). Yes, NY state banking is valuable and will help you with banking internships in the future.

    2. M&I - Nicole

      The major doesn’t matter as much as your experience and your whole story. If you can major/minor in Finance and/or Accounting there, I’d do that

      Given your lack of experience in the industry, I think you may still start off as an analyst even if you stay an extra year for the graduate degree. With the above being said, having the MBA, I believe, will help you in the long run, and I don’t think you’re giving up a lot (i.e. you won’t be having a full time job that you have to give up) by staying an extra year to earn that degree. As you grow older, you will have to take a lot more into consideration (family obligations, work etc etc) if you decide to go back to get your MBA, so in my humble opinion, if you want the degree and can do it in only one year after your 4 years, I’d do it…unless you are super bored in school and decide to dropout and start your own business – that’s a different story :)

  18. Navraj Singh

    Hey Nicole- I read M&I have partnered with AnEx Advantage program and I was trying to get into their summer session. Do you think it will give me an edge during SA recruiting next year (I am a rising junior)? As you attended MSB can you tell me how hard is to get a paid/unpaid Investment Banking internship in/around Washington D.C. area? I will also be attending Georgetown and I want to get some exerience. Thank you.

    1. M&I - Nicole

      It should be relatively easy and straightforward to get a paid/unpaid IB internship in/around DC. There are merits to the AnEx program.

      I’d suggest you to start looking for internships now/as soon as you start school. Yes an internship this summer is crucial if you want to break into IB after graduation

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