How long does it take to prepare for an investment banking interview?

Six to eight weeks at an hour or two a day is a realistic run from a standing start, and it beats cramming because technicals have to survive until interview day. What cannot be compressed is the last fortnight of answering out loud.

Do I have to memorise every technical?

No, and trying is how people fail. You need to be able to derive the answer, because the follow-up is always a variation on the question, and a memorised answer does not survive the variation.

My degree is not finance. Am I out?

No. Banks hire from every degree, and they screen for whether you can think and whether you did the work. The technicals are learnable in weeks; what they cannot teach you in an interview is whether you prepared.

Should I prepare in English or in Spanish?

In the language the process runs in. A London process is English end to end; a Madrid one is often English for the technicals and Spanish for the fit. Every guide here exists in both.

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The complete guide

Investment Banking Interview Prep, from zero to offer

Most candidates walk into investment banking interviews having read everything and practised nothing. Interviews aren't passed by reading — they're passed by performing under pressure. This guide is the roadmap: what gets tested, in what order, and exactly how to practise each piece. Every section links to a free question guide with model answers.

1. How IB recruiting works

Investment banking hires early and fast. Summer analyst (internship) recruiting is the main door, and it opens 12–18 months before the internship. Expect a first round (technical + fit), then a superday: back-to-back interviews, harder technicals, less patience for hesitation. The bar is simple — would I want this person on my deal team in front of a client? Everything below is how you clear it.

The calendar, and why it decides everything

The commonest mistake is not being weak on technicals, it is being ready in March for a process that closed in November. A typical UK and European cycle runs like this, and banks review applications as they arrive rather than after the deadline, so late is worse than imperfect.

12 to 18 months aheadSummer internship applications open. Spring weeks open even earlier.

September to NovemberCV screens, online tests and recorded video interviews. Mostly automated.

November to FebruaryFirst rounds with analysts and associates. Technical and fit, and where most people are cut.

January to MarchSuperdays and offers, rolling, with a short window to accept.

All yearOff-cycle and full-time roles, smaller in volume and less predictable.

Dates shift by bank and by country. The shape does not: you prepare the autumn before the summer you want to work.

2. Accounting — the entry ticket

If you can't walk the three statements and flow a change through them, the interview ends early. Master how the income statement, balance sheet and cash flow link; how a $10 change in depreciation flows through; working capital, deferred taxes and stock-based comp. Start here: accounting interview questions and the three-statement modeling questions.

3. Valuation & the DCF

Valuation is the technical heart of the interview. Know the three methods (comps, precedents, DCF), why EV/EBITDA is capital-structure neutral, and — above all — how to walk through a DCF: unlevered free cash flow, WACC, terminal value, bridge to equity. Go deeper with valuation interview questions, DCF questions, and what is WACC.

4. LBO & private equity logic

PE logic is tested in nearly every IB interview: what makes a good LBO candidate, how leverage amplifies returns, and the paper LBO you do in your head. Learn to walk through an LBO and the returns math (IRR vs MOIC) with LBO interview questions and private equity interview questions. Targeting the buy side itself? The complete private equity interview guide maps that whole process — headhunters, paper LBO, modeling test and deal discussion.

5. M&A & deal mechanics

M&A separates candidates who memorised formulas from those who understand deals: accretion/dilution, synergies, purchase accounting and the sell-side process. Practise M&A interview questions and accretion / dilution analysis.

6. Behavioral & fit — where offers are decided

Most rejections aren't technical. “Why investment banking?”, your CV story, and how you discuss a deal decide the offer once the technicals clear the bar. Nail them with why investment banking, the broader behavioral interview questions, and the full behavioral & fit interview guide.

7. The superday — and how to practise for it

Reading is not practising. The candidates who convert have answered out loud, under a clock, and been graded honestly — dozens of times. That's exactly what Deskcraft is: 5,000+ questions, AI voice mocks with a superday scorecard, a DCF/LBO model grader that flags hardcodes, live deal simulations, and a readiness score across every dimension a real process judges. Warm up with the superday interview questions, then train for real. And so nothing you drill fades before the interview, learn how to memorize IB technicals with spaced repetition.

Eight weeks, in the order that works

An hour or two a day beats a weekend of cramming, because the technicals have to survive until interview day and recall is built by repetition, not by intensity. This is the order we build a plan in, and the only rule that matters is that the last fortnight is spoken, not read.

Weeks 1 to 2Fundamentals. The three statements and how they link, enterprise value, and a DCF you can explain with no notes. Nothing else until this is automatic.

Weeks 3 to 4Your desk. Whatever your target actually asks: the paper LBO for PE and sponsors, credit and covenants for leveraged finance, real estate or markets if that is your route.

Week 5Tests. Numerical, verbal and logical tests, timed, every day. They are a cheap filter to fail and a cheap one to pass.

Weeks 6 to 7Out loud. Mock interviews with follow-ups. Record yourself once and you will fix more in an hour than in a week of reading.

Week 8Fit and markets. Your story, your deal, and what moved this week. Keep drilling technicals so nothing goes cold.

Investment banking interview FAQs

How long does it take to prepare for an investment banking interview?: Six to eight weeks at an hour or two a day is a realistic run from a standing start, and it beats cramming because technicals have to survive until interview day. What cannot be compressed is the last fortnight of answering out loud.
Do I have to memorise every technical?: No, and trying is how people fail. You need to be able to derive the answer, because the follow-up is always a variation on the question, and a memorised answer does not survive the variation.
My degree is not finance. Am I out?: No. Banks hire from every degree, and they screen for whether you can think and whether you did the work. The technicals are learnable in weeks; what they cannot teach you in an interview is whether you prepared.
Should I prepare in English or in Spanish?: In the language the process runs in. A London process is English end to end; a Madrid one is often English for the technicals and Spanish for the fit. Every guide here exists in both.

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