Among the fintechs that publish their numbers, "take rate" means about 0.16% of processed volume at Adyen and 8.8% of GMV at Affirm. Same two words, a fifty-five-fold gap. So when a prompt hands you "a payments company with a 2% take rate," you do not yet know what business you are looking at, and the interviewer knows it.
Fintech cases are decided in the first two minutes, before any framework, by three questions: who pays that rate, what is netted out of it before it becomes revenue, and who eats the loss when a transaction or a loan goes bad. I have scored candidates who built a tidy profitability tree on a volume figure they never questioned. The tree was fine. The trunk was rotten.
Below: the three questions, real filings, and a worked case.
Take rate is a range, not a number
Four audited sets of accounts; each percentage is one division.
| Company and period | Volume | Revenue | Revenue ÷ volume | What the rate is |
|---|---|---|---|---|
| Adyen, FY2024 | Processed volume €1,285.9bn | Net revenue €1,996.1m | 0.16%, about 16 bps | Acquiring fee, net of interchange and scheme fees |
| PayPal, FY2024 | TPV $1.68tn | Net revenues $31.8bn | 1.9% | Checkout, processing, and P2P blended; keeps 0.9% of TPV after costs and losses |
| Chime, 2024 | Purchase volume $115.2bn | Payments revenue $1,276.6m | 1.1% | Gross interchange, collected by two partner banks |
| Affirm, FY2025 | GMV $36.7bn | Revenue $3,224m | 8.8% | Merchant fees plus interest; keeps 4.0% after transaction costs |
Affirm's letter states that GMV "does not represent revenue earned by the Company," and PayPal's 2024 10-K says its active-account count "may not have a direct relationship to our operating results." Filings tell you which numbers to distrust. Prompts do not; that is what they are for.
Question one: who pays the rate?
Follow a $40 debit purchase. The merchant pays its acquirer a discount rate; most of it flows to the cardholder's bank as interchange, a slice to the network as scheme fees, and the acquirer keeps the rest. Every fintech take rate is one of those pieces.
An acquirer's take rate is the remainder, and the merchant is a customer it can price. A neobank's take rate is the interchange itself, set by network schedules and, for issuers with $10 billion or more in assets, by the Federal Reserve. Chime's S-1 says it earns most of its revenue through "interchange-based fees paid via the card networks, not paid to us by our members." Nobody at Chime sets that rate, so when a candidate proposes to "raise the take rate" at a neobank, I stop listening for a few seconds. It is like telling a utility to raise its regulated tariff.
| Model | Who pays | Netted before revenue is real | Who eats the loss |
|---|---|---|---|
| Acquirer or processor | The merchant | Interchange, scheme fees | The fintech: merchant fraud and chargebacks |
| Interchange-funded neobank | The merchant, via the network | Network fees, the bank's share, processing | Usually the fintech, for fraud and advance losses; the bank holds deposits and faces the regulator |
| Lender or BNPL | Merchant and borrower | Funding cost, credit losses, processing | Whoever holds the loan: the fintech or its forward-flow buyers |
Question two: what is netted out before it is revenue?
Every fintech reports a gross volume, a revenue, and what it keeps after paying everyone who made the transaction possible. The third has a different name everywhere: net revenue at Adyen, transaction margin dollars at PayPal, revenue less transaction costs at Affirm, transaction profit at Chime, defined in its S-1 as gross profit less transaction and risk losses. In the first quarter of 2025 Chime reported an 88% gross margin and a 67% transaction margin: twenty-one points of revenue left as transaction and risk losses. When I hand over an exhibit with GMV on it, I am waiting for one sentence: "what sits between this and revenue?" Candidates who don't ask compute the wrong margin with great confidence.
The denominator gets netted as well. "Active" means a money-movement transaction in the last calendar month at Chime (8.6 million Active Members in March 2025) and a transaction in the past twelve months at PayPal (434 million accounts) and Affirm (23.0 million consumers). Same word, a twelve-fold difference in window. When a prompt says "4 million active users," ask "active over what window, doing what?" The case writer had to choose, so the interviewer has an answer.
Question three: who eats the loss?
In fintech, loss is cost of goods sold, and a good prompt hides at least one kind: fraud, which scales with volume; credit losses, which arrive twelve to eighteen months after the growth that caused them; and program losses on advances, which scale with generosity.
Calibrate before you compute. US commercial banks charged off credit card balances at an annualized 3.82% in the second quarter of 2026, down from a 4.69% peak in the third quarter of 2024, and Affirm's allowance for credit losses was 5.6% of loans held for investment at June 30, 2025. A consumer lender showing a 1% loss rate has earned a question, not a compliment.
When a fintech holds no license, someone else's regulator can reach into its P&L: in June 2024 the Federal Reserve issued an enforcement action against Evolve Bank & Trust for failing to manage the risk of its fintech partnerships. And Chime's S-1 notes that transaction and risk losses rose after it launched MyPay, a pay-advance product, in July 2024, and that transaction margin will stay flat or fall as its liquidity products scale. The loss line is the product.
The regulator is a line in the P&L
Most industry cases treat regulation as a closing risk bullet. In US fintech it is a row in the revenue build.
| Date | What happened | Why it matters in a case |
|---|---|---|
| October 2011 | Regulation II caps debit interchange for issuers with $10 billion or more in assets at $0.21 plus 0.05% of the transaction plus a $0.01 fraud-prevention adjustment | Small issuers are exempt, so US neobanks issue through banks under $10 billion |
| December 2015 | The EU's Interchange Fee Regulation caps consumer debit interchange at 0.2% and credit at 0.3% | 0.2% of a €40 purchase is 8 cents. No app lives on that, so European neobank cases run on subscriptions, FX, and deposit interest |
| August 2025 | A North Dakota federal court vacates Regulation II in Corner Post v. Federal Reserve, a ruling stayed pending appeal; a Kentucky court upholds the rule in October 2025 | The cap applies while the Eighth Circuit appeal runs. Saying "uncertain as of September 2026" earns the point |
In 2024, by the Fed's own data, exempt debit transactions earned issuers $0.51 each on average, or 1.21% of value; covered transactions earned $0.23, or 0.47%. Exempt banks collect about 2.6 times as much per dollar spent. That ratio is the business model of a US neobank, and it is set in Washington.
Worked case: Kestrel and the $10 billion cliff
Prompt. Kestrel, an invented US consumer fintech, has 6 million customers, $18 billion of annual card spend, and a 1.4% take rate. The CFO's plan has profit growing in line with volume next year. Is the plan credible, and what should the CEO do?
The interviewer's answers. Merchants pay, via interchange, on debit cards issued by one partner bank with $8.5 billion in assets, growing 20% a year on Kestrel's own deposits. Netted: network fees, the bank's share, and processing, 12% of revenue. Losses: fraud and advance losses, carried by Kestrel, 20% of revenue. Denominator: 2.5 million of the 6 million moved money last month. Average ticket $40.
| Line | Math | Result |
|---|---|---|
| Transactions | $18.0bn ÷ $40 | 450 million |
| Revenue (gross interchange) | 1.4% × $18.0bn | $252m |
| Cost of revenue | 12% × $252m | $30.2m |
| Transaction and risk losses | 20% × $252m | $50.4m |
| Transaction profit | $252m − $30.2m − $50.4m | $171.4m, a 68% margin |
| Per active member, per "customer" | ÷ 2.5m, ÷ 6m | $101 a year, or $42, a number that describes nobody |
Next year. At 20% growth the bank crosses $10 billion within twelve months, and Kestrel's debit interchange drops to the cap: $0.21 plus 0.05% of $40 plus $0.01 is $0.24 a transaction, 0.60% of the ticket, against $0.56 today. On flat volume, revenue falls to 450 million × $0.24 = $108 million, down 57%. Cost of revenue tracks transactions and losses track volume, so both stay put. Transaction profit is $108m − $30.2m − $50.4m = $27.4 million, down 84%. The top line fell 57% and profit fell 84% because the lines beneath it did not move. Growth does not rescue it; growth is what pushes the bank over the line.
Recommendation. The plan assumes a rate Kestrel does not set will survive an event Kestrel is causing. Its real levers: a second exempt partner bank before the threshold, which buys time; a mix shift toward credit, which the cap does not cover: a secured credit card at, call it, 1.9% earns $0.76 on the same $40 ticket, three times covered debit, and Chime's credit interchange went from 17% of revenue in 2022 to 21% in 2024; and products it can price, such as a subscription tier. And do not say "raise the take rate."
Ned's rule. Never use a fintech number until you can say who pays it and who eats the loss behind it. If you cannot name both in one breath, it is a vanity metric, and I score it as one.
What the sheet rewards in the first minute
No firm publishes its scoring sheet, so this is mine: definitions clarified before computing, a structure that fits the model, numeracy on the right denominator, and a recommendation built on levers the company controls. The opening that earns all four takes under a minute: "Three clarifications before I structure. Who pays the 1.4%, and if it is interchange, which bank issues the cards? Is the $18 billion from all 6 million customers or from those active last month? And which losses sit with Kestrel rather than the bank? Then my structure is interchange yield, volume per active member, and the loss lines that scale with volume."
The weak opening, "revenue is customers times spend times take rate," treats a regulated rate as a price and registrations as payers. My estimate, not a study: in a first round of eight, two or three candidates ask a definitional question before structuring a fintech case. They are usually the two or three who advance.
Practice this today
One assignment, thirty minutes. Open any fintech's latest annual report or S-1. Find the volume, the revenue, and the "what we keep" line; divide; write the rate in basis points. Find how "active" is defined and note the window. Then finish the sentence "This company is paid by ___, nets out ___, and eats ___." Do three and the vocabulary stops sounding like revenue.
Converting 0.16% to 16 bps to 6 cents on $40 should take three seconds; the math drill times you on exactly that.
Then run a full case. The case library has fintech unit-economics cases among its 64 originals, the five-minute first rep scores three typed turns without an account, and the live voice case ends in a seven-score debrief. Everything is open for seven days, no card; then $120 for a recruiting season or $49 a month.
CoachNed is independent and not affiliated with McKinsey, BCG, Bain, the Big Four, or any company named here.
Frequently asked questions
What is the difference between GMV and revenue in a fintech case?
GMV is the value of transactions that passed through the platform; revenue is the slice the company is paid for handling them. Affirm booked 8.8% of GMV as revenue in fiscal 2025, Adyen about 0.16% of processed volume in 2024. Ask which one an exhibit shows before you compute.
Is a fintech case the same as a banking case?
No. A bank case runs on net interest margin, deposits, and capital; a fintech case runs on volume, take rate, activity, and loss lines. If the fintech holds loans on its own balance sheet you need both, so switch to the financial services approach mid-case, out loud.
What is the Durbin Amendment and why does it come up in fintech cases?
It is the 2010 US law under which the Federal Reserve capped debit interchange for issuers with $10 billion or more in assets at $0.21 plus 0.05% plus $0.01. Smaller banks are exempt and collected about 2.6 times as much per dollar in 2024, which is why most US neobanks issue through them and why the threshold is a live risk in any neobank case.
Sources
- Adyen publishes H2 2024 financial results — FY2024 processed volume and net revenue. Checked 2026-09-24.
- PayPal Reports Fourth Quarter and Full Year 2024 Results — FY2024 TPV, net revenues, transaction margin dollars, active accounts. Checked 2026-09-24.
- PayPal Holdings 2024 Form 10-K — active-account definition and quotation. Checked 2026-09-24.
- Affirm FQ4'25 shareholder letter, SEC exhibit — FY2025 GMV, revenue, transaction costs, active consumers, credit-loss allowance. Checked 2026-09-24.
- Chime Financial Form S-1, amended, 2025 — 2024 payments revenue and purchase volume, Active Member definition, small-issuer exemption, margins, MyPay losses. Checked 2026-09-24.
- Regulation II: average debit card interchange fee by payment card network — the cap, the exemption, and 2024 exempt versus covered averages. Checked 2026-09-24.
- ABA files amicus brief urging Eighth Circuit to reverse vacatur of Reg. II — Corner Post litigation status. Checked 2026-09-24.
- Federal Reserve enforcement action against Evolve Bancorp and Evolve Bank & Trust — the June 2024 action on fintech-partnership risk. Checked 2026-09-24.
- Charge-off and delinquency rates on loans and leases at commercial banks — quarterly credit card charge-off rates. Checked 2026-09-24.
- Fees for card-based payments: summary of Regulation (EU) 2015/751 — EU caps of 0.2% debit and 0.3% credit. Checked 2026-09-24.