Credit card companies make money in three ways: interest charged on balances that aren’t paid off, fees collected from cardholders, and interchange fees paid by merchants on every transaction. Interest is by far the biggest piece. Federal Reserve research attributes roughly 80 percent of aggregate credit card profitability to interest income, with late and other penalty fees contributing about 16 percent and miscellaneous sources covering the rest.1Federal Reserve. Credit Card Profitability With U.S. credit card balances reaching $1.28 trillion by the end of 2025, even small percentages produce enormous revenue.2Federal Reserve Bank of New York. Household Debt and Credit Report Q4 2025
Interest on Balances Is the Main Engine
When a cardholder doesn’t pay the full statement balance by the due date, the issuing bank starts charging interest on what remains. This is where most of the industry’s money comes from. The average credit card interest rate across all U.S. commercial bank accounts was about 21 percent as of late 2025.3Federal Reserve Bank of St. Louis. Commercial Bank Interest Rate on Credit Card Plans, All Accounts On a $5,000 balance at that rate, an issuer earns over $1,000 a year from a single account.
Interest is calculated daily. The annual rate gets divided by 365 to produce a daily periodic rate, which is applied to the balance owed at the end of each day. At 21 percent APR, that daily rate is about 0.058 percent, and it compounds through the billing cycle. Under Regulation Z, issuers have to disclose the APR clearly so consumers can compare products.4Consumer Financial Protection Bureau. 12 CFR 1026.14 – Determination of Annual Percentage Rate
Cardholders who pay their statement in full each month owe no interest because of the grace period. The CARD Act requires issuers to deliver bills at least 21 days before the due date.5Consumer Financial Protection Bureau. What Is a Grace Period for a Credit Card? The industry calls these full-payers “transactors,” and they are the least profitable cardholders from an interest standpoint. The most profitable are “revolvers,” who carry a balance month after month and generate finance charges every cycle.
The rates climb higher when payments fall behind. If a cardholder is more than 60 days late, many issuers impose a penalty APR that can reach roughly 29 percent, and it can apply to the entire outstanding balance rather than just the overdue portion. The CARD Act requires issuers to review these penalty rate increases every six months and restore the original rate if payment behavior improves.
Not every loan gets repaid, and issuers price for that. The charge-off rate on credit card loans across all U.S. commercial banks was 4.03 percent in the fourth quarter of 2025, meaning about four cents on every dollar lent was written off as uncollectable.6Federal Reserve Bank of St. Louis. Charge-Off Rate on Credit Card Loans, All Commercial Banks That expected loss is one reason credit card APRs sit so far above mortgage or auto rates. Issuers rely on interest from paying customers to cover losses from those who default.
Fees Paid by Cardholders
Fees form a second revenue stream that runs independently of whether a customer carries a balance, which makes them valuable during stretches when consumers pay down debt.
- Annual fees. Premium cards charge anywhere from $95 to $895 or more, usually tied to perks like lounge access, travel credits, or elevated rewards. Entry-level and many mid-tier cards charge nothing, leaning on interest and interchange instead.
- Late payment fees. Under Regulation Z, penalty fees must be reasonable and proportional. Issuers can use a cost-based analysis or the CFPB’s safe harbor, currently $32 for a first late payment and $43 for another late payment within the next six billing cycles, adjusted annually. The CFPB finalized a rule in 2024 that would have capped late fees at $8 for large issuers, but a federal court voided it after the agency acknowledged it was inconsistent with the CARD Act.7eCFR. 12 CFR 1026.52 – Limitations on Fees8Consumer Financial Protection Bureau. CFPB Bans Excessive Credit Card Late Fees, Lowers Typical Fee From $32 to $8
- Cash advance fees. Pulling cash against a credit line usually costs $10 or 3 to 5 percent of the amount, whichever is greater. Interest starts accruing immediately with no grace period, which makes cash advances one of the most expensive ways to borrow.
- Foreign transaction fees. Most cards add 1 to 3 percent on purchases made outside the U.S. or in foreign currencies. Part goes to the network for currency conversion, part goes to the issuer. Some travel cards waive it.
- Balance transfer fees. Moving debt from one card to another generally costs 3 to 5 percent of the transferred amount. Issuers frequently pair these with a promotional low or zero percent APR, betting the balance will still be there when the regular rate kicks in.
Interchange Fees Paid by Merchants
Every credit card transaction runs through a loop involving four parties: the cardholder, the merchant, the merchant’s acquiring bank, and the cardholder’s issuing bank, connected by a network like Visa or Mastercard. The issuing bank checks the credit line and approves or declines. The acquiring bank handles the merchant’s account. The network runs the technology and enforces the rules. The issuing bank carries the credit risk; if the cardholder never pays, the issuer eats the loss.
Merchants pay for the privilege of accepting cards through a merchant discount rate that typically runs 1.5 to 3.5 percent of the transaction. That percentage gets split three ways. The largest slice, called the interchange fee, goes to the issuing bank. On a $100 sale with a 2 percent interchange rate, the issuer collects $2.00 for extending credit and taking the non-payment risk. Networks collect assessment fees of roughly 0.13 to 0.14 percent of processed volume, which fund their data centers, fraud systems, and authorization infrastructure. The acquiring bank keeps what’s left, usually the thinnest margin of the three.
Not every network uses the four-party model. American Express and Discover historically operate a closed-loop structure where the network itself is both the issuer and the acquirer, capturing revenue from both sides instead of splitting it with partner banks. Both companies now also license other banks to issue on their networks, which blurs the distinction in practice.
Credit card interchange remains largely unregulated. The Durbin Amendment to the Dodd-Frank Act capped interchange only on debit cards, currently limiting fees to $0.21 plus 0.05 percent of the transaction, plus a $0.01 fraud-prevention adjustment, for issuers with more than $10 billion in assets.9Federal Reserve. Average Debit Card Interchange Fee by Payment Card Network Credit cards, with their higher risk profile and richer rewards, carry no federal interchange cap.
Where Rewards Actually Come From
Cashback, miles, and points are funded primarily out of interchange. Industry estimates put 40 to 70 percent of each interchange dollar toward rewards, with the rest covering fraud losses, credit risk reserves, and issuer margin. A card offering 2 percent cashback on a transaction with a 2.2 percent interchange rate leaves the issuer very little after the reward is paid.
That math shapes the whole product line. Premium cards carry higher interchange rates, which is why some small merchants would prefer that customers reach for a basic card or debit. It also explains why issuers push premium cards hard: higher interchange per swipe, plus annual fees, make these accounts more profitable even after paying out richer rewards. And it explains a cross-subsidy at the heart of the model. Merchants absorb higher processing costs and spread them across all customers through prices, while rewards cardholders recover a share of that cost through points or cashback. Customers paying cash or debit help fund rewards they never see.
Rewards also drive volume. A cardholder who routes every purchase through one card to maximize points generates more interchange for the issuer on each swipe. The rewards are the hook, and the spending pattern is what pays off.
Securitization, Data, and Ancillary Revenue
Issuing banks need capital to extend the credit lines their business runs on. Deposits fund some of it. Many issuers also securitize, bundling thousands of card receivables into a pool and selling securities backed by that pool to investors. Investors receive the stream of cardholder payments; the issuer gets an upfront lump of cash to lend out again. Securitization also moves receivables off the balance sheet, reducing the regulatory capital the bank must hold, and it diversifies funding beyond deposits. The trade-off is that a slowdown in investor appetite, as happened in 2008, can tighten consumer credit even when cardholders are paying on time.
Transaction data is a quieter revenue line. By analyzing spending across millions of accounts, card companies generate anonymized market insights that retailers, marketers, and investors pay for. A restaurant chain can see whether category spending is rising in a metro area. A real estate investor can track discretionary spending shifts. The data is aggregated and stripped of personal identifiers, but the volume makes patterns commercially useful.
Issuers also earn referral income when cardholders book hotels or buy products through their shopping portals, collecting commissions from the partner merchants. And they sell add-on services such as identity theft monitoring, credit score tracking, purchase protection, and travel insurance, sometimes bundled into premium tiers and sometimes as standalone subscriptions. Margins on these are high because the issuer already has the customer relationship and the billing pipe.
What Federal Rules Restrict
Several federal laws limit how far issuers can push their revenue practices. The CARD Act of 2009 required the 21-day billing window, regulated penalty fees, banned most retroactive interest rate increases on existing balances, required payments above the minimum to be applied to the highest-rate balance first, and restricted marketing to consumers under 21. Those rules didn’t eliminate issuer revenue so much as redirect it. Issuers responded by raising standard APRs, increasing annual fees, and leaning more heavily on interchange.
Federal law also caps a cardholder’s liability for unauthorized charges at $50, and most major networks waive even that. Debit cards operate under a different framework with weaker consumer protections, which is one reason credit cards remain attractive to consumers despite their higher cost.10Consumer Financial Protection Bureau. 12 CFR 1005.6 – Liability of Consumer for Unauthorized Transfers The billing dispute process under the Fair Credit Billing Act gives cardholders 60 days to challenge a charge in writing, and issuers cannot try to collect the disputed amount during the investigation.11Office of the Law Revision Counsel. 15 U.S. Code 1666 – Correction of Billing Errors Together these rules constrain a few of the model’s sharper edges without changing the basic sources of revenue.