Fintech companies work by placing a software layer between you and traditional banking infrastructure, handling everything from payments to lending to investing through apps and digital platforms instead of bank branches. Behind the scenes, most fintechs don’t hold a banking license themselves. They connect to licensed banks through APIs (application programming interfaces, which are standardized ways for software systems to talk to each other) and use that bank’s charter to offer you FDIC-insured accounts, loans, and payment processing.
The Technology Stack Behind Fintech
The core technology that makes fintech possible is a model called Banking-as-a-Service, or BaaS. In traditional banking, you go to the bank, whether that’s a branch, the bank’s own app, or its website. Under BaaS, the bank comes to you through other platforms. A licensed bank opens up its infrastructure through APIs so that a fintech company can build its own user experience on top of the bank’s regulatory foundation.
Here’s what that looks like in practice. When you open an account with a fintech app like Chime or Varo, your money is actually held at a partner bank. The fintech handles the interface you see on your phone: the sign-up flow, the spending notifications, the savings tools. The partner bank handles the regulated parts: holding your deposits, issuing your debit card, and providing FDIC insurance. APIs shuttle information back and forth between the fintech’s front end and the bank’s core systems in real time, so your balance updates instantly when you make a purchase.
Running this kind of setup requires cloud-based infrastructure that can scale quickly and handle millions of transactions. Banks offering BaaS need to manage API rate limits (caps on how many requests can be processed per second), maintain backup plans for outages on the fintech’s side, and keep ledgering systems perfectly synchronized so your account balance is always accurate. When you tap your phone to pay for coffee and see the transaction appear in your app three seconds later, that entire chain of connections is firing behind the scenes.
How Fintech Companies Make Money
Most fintech apps are free to download and use for basic features, which raises an obvious question: where does the revenue come from? The answer depends on the type of fintech, but a few models dominate.
Interchange fees: Every time you swipe a debit or credit card, the merchant pays a fee, typically around 3% of the transaction. About half of that, roughly 1.5%, goes to the card issuer as an “interchange fee.” For fintechs that give you a debit card, like Chime and Varo for consumers or Ramp and Divvy for businesses, interchange is the primary revenue driver. If you spend $3,000 a month on your fintech debit card, the company earns roughly $45 from your usage alone, and that scales across millions of cardholders.
Subscription and freemium tiers: Many fintech apps offer a free base product with limited features, then charge a monthly or annual fee for premium tools. A budgeting app might let you track spending for free but charge $5 a month for investment tracking, credit monitoring, or advanced reports. This recurring revenue gives the company predictable income regardless of how markets or interest rates shift.
Interest on loans: Fintechs that offer lending, whether personal loans, buy-now-pay-later plans, or crypto-backed borrowing, earn revenue from the interest you pay. Some platforms use lending as an add-on to a product that initially attracted you for a different reason. Coinbase, for instance, lets customers borrow up to $1 million against their cryptocurrency holdings and charges interest on those loans.
Transaction and trading fees: Platforms focused on investing or cryptocurrency charge fees on trades. Coinbase uses a tiered structure: flat fees ranging from $0.99 to $2.99 for transactions under $200, a 1.49% fee for bank-funded transactions over $200, and 3.99% for debit card purchases. Even platforms that advertise “commission-free” stock trading often earn money through payment for order flow, where market makers pay the platform for routing trades to them.
The Partner Bank Relationship
Because most fintechs don’t have their own banking charter, they rely on partnerships with licensed banks to operate legally. This arrangement lets the fintech move fast and focus on building software while the partner bank provides the regulatory backbone: deposit insurance, compliance with lending laws, and access to payment networks like Visa and Mastercard.
These partnerships also allow fintechs to offer products in ways traditional banks cannot easily replicate. Research from the Federal Reserve found that strategic partnerships between fintech companies and specialist banks often target near-prime and low-prime consumers for debt consolidation loans. The partner bank’s federal charter can preempt certain state-level interest rate caps, letting the fintech lend to higher-risk borrowers in markets where a state-chartered lender might not be able to offer the same product profitably. This is one reason you’ll see fintech lenders approve applicants that traditional banks turn away, though the trade-off is often a higher interest rate for the borrower.
The regulatory relationship is layered. Federal banking regulators oversee the partner bank, and by extension, they scrutinize how that bank manages its fintech partnerships. If the fintech mishandles customer data or violates lending rules, the partner bank faces regulatory consequences. This creates a chain of accountability that, in theory, protects you even though you never interact with the partner bank directly.
Embedded Finance: Fintech Inside Non-Financial Apps
Fintech doesn’t only live in dedicated finance apps. Increasingly, financial services are embedded directly into platforms you use for shopping, freelancing, or running a business. This is called embedded finance, and it works through the same API infrastructure that powers standalone fintech apps.
When a ride-sharing app lets drivers cash out their earnings instantly, that’s embedded finance. When an e-commerce marketplace offers sellers a loan based on their sales history, that’s a fintech lending product built into a non-financial platform. When a freelance marketplace handles invoicing, tax withholding reminders, and direct payments all in one dashboard, APIs are connecting the platform to banking and payroll infrastructure behind the scenes.
The appeal for the platform is that it keeps users from leaving to handle financial tasks elsewhere. The appeal for you is a simpler experience. Instead of applying for a business loan at a bank, uploading months of financial statements, and waiting days for approval, you might get a pre-approved credit offer inside the platform that already has your transaction data. The loan application takes minutes because the platform already knows your revenue history.
How Different Fintech Sectors Operate
Fintech isn’t one industry. It’s a collection of sectors, each automating a different piece of traditional finance.
- Payments: Companies like Venmo, Cash App, and Stripe replace cash and checks with instant digital transfers. They sit between your bank account and the person or business you’re paying, using APIs to move money through existing bank rails while giving you a faster, more convenient interface.
- Lending: Online lenders use algorithms to assess your creditworthiness, often pulling data beyond your traditional credit score (like income verification, banking history, or even education). Approval decisions that take weeks at a bank can happen in minutes. The lender funds your loan through a partner bank or from its own capital, depending on its structure.
- Investing: Robo-advisors and trading apps automate portfolio management or give you direct access to stock and crypto markets. They typically hold your assets through a licensed brokerage or custodian while providing the interface and tools on top.
- Neobanking: Digital-only banks like Chime and Current offer checking and savings accounts entirely through an app, with no physical branches. Your deposits sit at a partner bank, but every interaction happens through the neobank’s software.
- Insurance: Insurtech companies use data and automation to underwrite policies, process claims, and price coverage more quickly than traditional insurers. Some are licensed carriers themselves, while others partner with established insurance companies.
Each sector follows the same basic pattern: take a financial process that used to require paperwork, branch visits, or phone calls, then rebuild it as software. The licensed financial institution still exists in the background, but the experience you see is designed by a technology company focused on speed, simplicity, and lower fees.
What Happens to Your Data
Fintech runs on data. When you connect your bank account to a budgeting app or apply for a loan through an online lender, you’re sharing financial information that powers the service. Data aggregators act as intermediaries, using APIs to pull your transaction history, balances, and account details from your bank and deliver them to the fintech app you’ve authorized.
Open banking regulations in some markets require banks to share customer data with third-party providers when the customer gives consent. In the U.S., regulatory frameworks around open banking are still evolving, but the practical reality is that millions of Americans already share their bank data with fintech apps every day. The fintech uses that data to categorize your spending, verify your income for a loan application, or recommend financial products. Your authorization is what triggers the data flow, and you can typically revoke access through the fintech app or your bank’s settings.
The trade-off is straightforward: you get a more personalized, automated financial experience, and the fintech gets access to data that helps it serve you and, in many cases, target you with additional products. Understanding that exchange is the first step toward using fintech tools on your own terms.