How to Answer “Tell me about a time you had to make a decision with limited information.” in Investment Banking Interviews
In investment banking interview prep, this is one of the most common investment banking decision-making questions: “Tell me about a time you had to make a decision with limited information.” The goal isn’t to prove you always had the “right” answer—it’s to show how you think when the data is messy, time is tight, and the stakes are real.
A strong response uses a simple decision-making framework, states your assumptions clearly, shows risk management, and ends with what you learned and how you’d apply it as an analyst.
What Interviewers Look For in Behavioral Interviews Under Uncertainty
In behavioral interviews for investment banking, interviewers use this prompt to assess judgment under uncertainty. They want evidence you can make progress without perfect information—something that happens constantly on live deals (incomplete diligence, shifting management guidance, limited time to build materials).
They are also testing how you structure decisions: whether you identify the key driver(s), separate facts from assumptions, and choose a practical path forward (e.g., “best available answer now, plus a plan to validate”). This is closely linked to decision-making in finance interviews because it mirrors day-to-day analyst work: prioritising the 2–3 inputs that move outcomes, documenting uncertainty, and communicating trade-offs.
Finally, they’re evaluating professionalism: do you escalate appropriately, pressure-test your work, and learn from outcomes? A good answer shows ownership, not heroics—especially in situations where you cannot fully control the information set.
Framework for Investment Banking Decision-Making Questions (4 Steps)
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Step 1: Set the scene and define the decision (scope + constraints)
Open with a crisp setup: your role, the context, and the decision that had to be made. Make the constraint explicit—limited data, time pressure, conflicting inputs, or an unclear stakeholder goal. This anchors the story so it doesn’t sound like you were careless; it shows you recognised the uncertainty.
Then define what “good” looked like. In banking-style work, that usually means a decision that is directionally correct, defensible, and reversible where possible. Say what was at stake (client impact, deadline, reputational risk, team dependency) and what you controlled vs. what you didn’t.
Tip: keep this to 20–30 seconds out loud. The interviewer should understand the problem instantly: What choice did you need to make, by when, and with what information missing?
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Step 2: Use a decision-making framework (facts, assumptions, options, risks)
Next, show your process. A simple decision-making framework that works well for investment banking case studies and behavioural interview questions is:
- Facts: what you knew with confidence (internal numbers, prior comps, guidance ranges, email confirmations).
- Assumptions: what you estimated, and why (proxy metrics, triangulation, conservative ranges).
- Options: the 2–3 realistic paths (ship a v1, wait for data, escalate for a decision).
- Risks + mitigants: how you reduced downside (sensitivities, ranges, clear labels, approvals).
Make it obvious you focused on the highest-leverage inputs rather than boiling the ocean. If you used quick validation (cross-checking with a second source, sanity checks vs. comps, reconciling to historicals), call that out—this is “navigating limited information in investment banking interviews” in action.
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Step 3: Decide, communicate, and document (so others can trust the output)
Explain what you chose and how you communicated it. In finance roles, the “decision” is often paired with a deliverable: a slide, a model output, a client email, or an internal recommendation. Interviewers want to hear that you didn’t just pick an answer—you made it usable for the team.
Include three elements:
- Decision + rationale: one sentence on why this option was best under the constraints.
- Transparency: how you labelled uncertainty (ranges, flags, open items, assumptions page).
- Escalation: if appropriate, who you aligned with (associate/VP, project lead) and what you asked for (a call on a key assumption, permission to use a conservative proxy).
This shows maturity: you can move quickly, keep stakeholders informed, and avoid surprises—core skills for an analyst on tight timelines.
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Step 4: Validate fast and reflect (what changed after new info)
Close the story by showing what happened after the decision and what you learned. Limited-information decisions are rarely the final step; they’re a checkpoint.
Describe how you validated once more information arrived: updating assumptions, comparing your proxy to actuals, running sensitivity cases, or reconciling to a final number. If the decision was materially impacted, explain how you handled the change (e.g., “we updated the deck and called out the delta and driver”).
End with one practical takeaway you now apply in investment banking interview strategies for behavioral questions and on-the-job work: for example, always stating the decision driver, documenting assumptions, using ranges, and building a quick verification plan. This turns the story from “I guessed” into “I made a controlled decision under uncertainty.”
Sample Answer: Limited-Information Decision (IB Analyst)
In investment banking, you rarely have perfect information, so my approach is to identify the key decision driver, make a defensible assumption, and build in a quick validation plan.
In a prior internship, I was supporting an associate preparing a client update on valuation for a potential sell-side. The night before the draft had to go out, we were missing a clean, updated segment breakdown, but the associate still needed a directional valuation page and a set of comps to anchor the discussion.
I first separated what we knew versus what we didn’t. We had total revenue, historical segment mix from the last annual report, and management commentary suggesting one segment had accelerated. We didn’t have the latest split or confirmation of margin differences by segment. I outlined two options to the associate: wait for the segment detail and risk missing the deadline, or produce a version using a conservative range for segment mix and show the impact via sensitivities.
I recommended the second option. I built the comps set, used the historical mix as a base case, and created a downside/upside mix scenario based on the commentary, clearly labelling the assumptions on the slide. I also added a short note on the open item and queued a follow-up with the finance contact first thing in the morning to validate.
The next day, we received the updated split; it was within my range, so the valuation conclusion didn’t change, and we updated the slide with the confirmed numbers. The main lesson I took away is to be transparent about assumptions and manage risk with ranges and sensitivities so the team can move forward without overstating certainty.
- Start with a one-sentence “how I decide” principle; it gives structure immediately.
- Make the missing information explicit, then show how you reduced the uncertainty (ranges, proxies, sensitivities).
- Show appropriate escalation and communication—analysts are trusted when they document assumptions clearly.
- Quantify impact where possible (even if just “within my range” or “no change in conclusion”).
- End with a repeatable takeaway that maps to analyst work on models, decks, and deadlines.
Common Mistakes in Decision-Making in Finance Interviews
- Telling a story where the “decision” is vague (e.g., “I worked hard”) instead of a clear choice with trade-offs.
- Implying you ignored missing data rather than acknowledging uncertainty and managing it with assumptions and checks.
- Over-rotating into technical detail and forgetting the behavioural core: judgment, communication, and ownership.
- Skipping escalation: acting as if you made a high-stakes call alone when a quick alignment with an associate/manager would be expected.
- Not explaining what happened after the decision—interviewers want to see validation and learning, not just the initial guess.
- Choosing an example where the lesson is “I was wrong” without showing controls (sensitivities, conservative ranges, mitigants) and what you changed next time.
Follow-Ups: Probing Your Judgement, Assumptions, and Risk Control
What was the biggest assumption you made, and how did you choose it?
I picked the assumption that drove the output most and triangulated it using historical disclosures, a conservative range, and a sensitivity to show impact if it was wrong.
How did you communicate uncertainty without undermining confidence?
I used ranges and clearly labelled assumptions, then explained what would change the conclusion and what we were doing to validate quickly.
When would you escalate versus deciding independently?
If the assumption could change the recommendation, affect client messaging, or create reputational risk, I align with the associate/VP; otherwise I proceed with a documented, reversible approach.
How do you handle it if new information later contradicts your decision?
I update the output promptly, quantify the delta and driver, and communicate the change clearly—owning the update rather than defending the old assumption.
Can you give another example of decisions made with limited information in finance?
Examples include using proxy KPIs to estimate quarterly performance, selecting a comps set before a full diligence readout, or drafting an initial deck narrative while key diligence items are still open.
Investment Banking Interview Prep: How to Practise This Story
- Write three versions of this story (internship, university project, work experience) so you can pick the most relevant to the interviewer and deal context.
- Rehearse a 2-minute delivery: 30s setup, 60s process/decision, 30s outcome/learning; keep it tight for behavioural interview questions.
- Explicitly say “facts vs assumptions” in your answer—this is an easy signal of decision-making frameworks under pressure.
- Add one sentence on risk control (ranges, sensitivities, conservative case) to match decision-making in finance interviews.
- Practise with AceTheRound by running the question twice: first for structure, second to sharpen assumptions and reduce filler words.
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