Estimation question
How do you measure the market size for Revolut?
- Amazon Pay
- Estimation
- Medium
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What this question tests
Tests structured market-sizing (TAM/SAM/SOM) applied to a specific fintech product, including picking the right base population and monetization unit.
How to approach it
- Clarify what 'market size' means here: likely the addressable market for Revolut's core offering, multi-currency accounts and cards, mainly in Europe with growing US/global presence.
- Define the top-of-funnel population: adults in Revolut's active countries who travel internationally, hold foreign currency, or want a digital-first bank alternative.
- State an assumption for TAM, for example roughly 450 million adults across Revolut's core European markets, of which a meaningfully sized segment are digitally active banking users.
- Narrow to SAM: the subset who are likely candidates for a neobank, for example younger, tech-comfortable, urban populations, clearly marked as an assumption, maybe 25 to 30 percent of that base.
- Narrow to SOM: Revolut's realistic near-term capture given current market share and competition from Monzo, N26, and traditional banks' digital offerings, perhaps a low single-digit percent of SAM.
- Convert to revenue: multiply the estimated user count by an assumed average revenue per user (from card interchange, subscriptions, FX fees) to size the addressable revenue opportunity.
What a strong answer includes
- Walks through TAM, SAM, SOM explicitly and states each number as a clearly labeled assumption rather than presenting them as facts.
- Picks a sensible ARPU assumption, for example a blended few tens of dollars a year from a mostly free-tier user base plus a smaller paying-tier subset, and shows the arithmetic.
- Sanity-checks the result against something known, like comparing the implied user count to a rough estimate of Revolut's publicly discussed user base.
- Notes that market size should be split by product line (spending accounts vs. crypto vs. stock trading) since they have different addressable populations.
Common mistakes
- Giving a single top-down number with no visible breakdown or assumptions.
- Confusing market size (opportunity) with Revolut's actual current revenue or user count.
- Not sanity-checking the estimate against any real-world reference point.
Likely follow-up questions
- Which assumption in your estimate has the most uncertainty, and how would you validate it?
- How would market size differ if you excluded the crypto trading product?
- How would you size the opportunity in a new market Revolut is entering?
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More questions from Amazon Pay
Learn the skill behind it
Chapters of the AI PM course that teach what this question tests.
- Chapter 2: Data fluency: SQL, logs, and reading the truth yourself
- Chapter 9: Prove it paid off: outcomes, economics, and pricing
- Chapter 14: Get the job: the AI PM interview loop