Bank credit risk is the possibility that a borrower or trading partner fails to repay what they owe, costing the bank interest income, principal, or both. Because lending generates most of a bank’s revenue, even a small rise in loan failures can eat into earnings and erode the capital that protects depositors. Managing that risk shapes almost every decision a bank makes, from the interest rate on a mortgage to how much cash it keeps in reserve.
The Main Forms Credit Risk Takes
Credit risk is not one thing. Banks separate it into categories because each behaves differently and calls for different controls.
Default Risk
The most direct form: a borrower stops paying. Regulators worldwide treat a loan as “non-performing” once it goes 90 days without a scheduled payment.1European Central Bank. What Are Non-Performing Loans (NPLs)?2Bank for International Settlements. Guidelines for Definitions of Non-Performing Exposures and Forbearance Once a loan crosses that line, interest income stops and the bank may have to write down part or all of the principal. If the borrower has no seizable assets and no path back to payments, the entire balance can be lost.
Concentration Risk
Concentration builds when too much of a bank’s lending book is tied to one industry, one region, or one type of borrower. A bank stacked with hospitality loans in a single metro area faces the prospect that one regional downturn hits every loan at the same time. Federal law caps how much a national bank can lend to any single borrower at 15 percent of capital and surplus, with an extra 10 percent allowed if the excess is fully secured by readily marketable collateral.3eCFR. 12 CFR Part 32 – Lending Limits Banks layer their own internal limits by industry, geography, and loan type on top of that.
Counterparty Risk
Counterparty risk lives in the trading book. When a bank enters a swap, forward, or other derivative, the other side owes payments that move with the market. If that counterparty goes bankrupt before final settlement, the bank loses the market value of the position. Master netting agreements let a bank offset gains and losses across every trade with the same counterparty so only one net amount is owed at default.4Bank for International Settlements. Standardised Approach: Credit Risk Mitigation
Sovereign Risk
When a bank holds government bonds or lends to foreign governments, it takes on sovereign risk. Under the Basel standardized approach, bonds from countries rated AAA to AA- carry a 0 percent risk weight, so the bank holds no extra capital against them. That weight jumps to 100 percent for BB+ to B- and reaches 150 percent below B-.5Bank for International Settlements. Standardised Approach: Individual Exposures A downgrade ripples further than the bond itself: no claim on an unrated bank can receive a risk weight lower than the sovereign where it is incorporated.6Bank for International Settlements. International Convergence of Capital Measurement and Capital Standards: A Revised Framework
How Banks Decide Who to Lend To
The first defense against credit risk is not making bad loans in the first place. Lenders combine several tools to size up a borrower before advancing a dollar.
Credit History and Scores
Lenders start with a credit report. The widely used FICO model produces a number between 300 and 850 based on payment history, amounts owed, length of credit history, new inquiries, and credit mix.7MyCreditUnion.gov. Credit Scores Higher scores signal lower risk. Serious derogatory marks weigh heavily: a bankruptcy filing under any chapter of the Bankruptcy Code can stay on a credit report for up to ten years from the date the court enters the order for relief.8Consumer Financial Protection Bureau. How Long Does a Bankruptcy Appear on My Credit Report?
Debt-to-Income and the Ability-to-Repay Rule
Debt-to-income (DTI) compares monthly debt payments to gross monthly income. Conventional mortgage guidelines set a baseline around 36 percent for manually underwritten loans, though automated systems can approve DTIs as high as 50 percent when credit scores and reserves support it.9Fannie Mae. Fannie Mae Selling Guide – Debt-to-Income Ratios For residential mortgages, Regulation Z requires a lender to make a reasonable, good-faith determination that the borrower can actually repay, weighing income, employment, current debts, and the monthly payment. The rule does not impose a single hard DTI cap.10eCFR. 12 CFR 1026.43 – Minimum Standards for Transactions Secured by a Dwelling High ratios still matter, because a thin income cushion leaves no room to absorb a job loss.
Collateral
Collateral gives the bank a fallback when cash flow dries up. Mortgage lenders order a professional appraisal and typically cap the loan at 80 percent of value; the 20 percent equity cushion protects the bank if prices fall. Borrowers who put down less usually pay private mortgage insurance. For business loans secured by equipment, inventory, or receivables, the bank perfects its claim by filing a UCC-1 financing statement with the relevant state office.
Ongoing Covenants for Business Borrowers
Commercial credit is not a one-time check. Loan covenants require the borrower to maintain specific financial benchmarks throughout the life of the loan. Typical financial covenants include a minimum debt-service coverage ratio, a maximum debt-to-equity ratio, and limits on capital expenditures, monitored quarterly. A breach lets the lender accelerate repayment or impose penalties, catching deterioration before it turns into a full default.
External Economic Factors
A borrower who looks safe today can look risky tomorrow. Rising unemployment in the borrower’s industry raises the odds of income loss. Rate hikes on variable-rate debt push monthly payments higher on households and businesses that were already stretched. Banks watch these indicators constantly because a recession-driven wave of defaults hits the loan book faster than any internal model can reprice.
Putting a Number on the Risk
Qualitative judgments have to be converted into dollars. Three metrics do the work, and multiplying them produces the expected loss figure that drives loan pricing and reserves.
Probability of Default
Probability of default (PD) is the statistical likelihood a borrower stops paying within a one-year window. Banks estimate it from historical loss data and current credit indicators. A strong score and stable income yield a low PD; recent delinquencies and falling revenue yield a high one. PD feeds directly into pricing: the higher the estimate, the more interest the bank charges to compensate.
Exposure at Default
Exposure at default (EAD) estimates the total amount owed at the moment of default. For a term loan, that is mostly remaining principal plus accrued interest. Revolving credit is trickier because the borrower can draw down unused capacity right before defaulting, so banks apply credit conversion factors to unused commitments. Under the Basel framework’s foundation approach, the conversion factor for unused credit lines follows the same percentages used in the standardized approach.11Bank for International Settlements. IRB Approach: Risk Components Borrowers in distress tend to max out available credit before missing a payment, which is why the committed-versus-uncommitted distinction matters.
Loss Given Default
Loss given default (LGD) is the percentage of the exposure the bank actually loses after selling collateral and pursuing recovery. Foreclose on a house and recover 60 cents on the dollar, and LGD is 40 percent. Well-secured loans have far lower LGDs than unsecured credit cards, which is a large part of why secured borrowing carries lower interest rates.
Expected Loss
The three metrics multiply together. A $500,000 loan with a 2 percent PD and a 40 percent LGD carries an expected loss of $500,000 × 0.02 × 0.40, or $4,000. Banks run that calculation across every loan, and the aggregate becomes the baseline for the allowance for credit losses on the balance sheet.
Internal Grading and Loss Reserves
Behind the metrics sits a grading system. Interagency guidance used by the OCC, FDIC, and Federal Reserve classifies problem loans into five categories:12Office of the Comptroller of the Currency. Comptroller’s Handbook: Rating Credit Risk
- Pass, meaning no signs of weakness; larger banks split this into multiple grades to distinguish among healthy credits.
- Special Mention, meaning potential weaknesses that deserve close attention but do not yet warrant an adverse classification.
- Substandard, meaning well-defined weaknesses that jeopardize full repayment, with a distinct possibility of some loss.
- Doubtful, meaning collection in full is highly questionable.
- Loss, meaning the exposure is considered uncollectible and not worth carrying as a bankable asset.
The people assigning grades have to be independent from the people making the loans. Interagency guidance requires the credit review function to report directly to the board or a board committee, not to lending officers. Smaller institutions can rely on qualified staff or outside directors, but those individuals cannot have originated or approved the specific credits they are reviewing.13Federal Deposit Insurance Corporation. Interagency Guidance on Credit Risk Review Systems
Loss recognition on the accounting side runs on the Current Expected Credit Losses standard. Under CECL, banks estimate lifetime expected credit losses at the moment a loan is originated, rather than waiting for losses to become “probable.” The methodology, codified in FASB ASC Topic 326, applies to financial assets carried at amortized cost, net lease investments, and off-balance-sheet credit exposures. It took effect for large SEC filers in fiscal years beginning after December 15, 2019, and for all other institutions in fiscal years beginning after December 15, 2022.14Federal Deposit Insurance Corporation. Current Expected Credit Losses (CECL) The practical result is that when the outlook darkens, the allowance rises immediately instead of waiting for actual missed payments.
Tools for Reducing Risk Already on the Books
Credit Default Swaps
A credit default swap lets a bank pay a periodic premium to a third party in exchange for protection against a referenced borrower’s default. If a credit event occurs, the protection seller pays the notional value; if the borrower stays current, the seller keeps the premiums.15Federal Reserve. A Look Under the Hood: How Banks Use Credit Default Swaps The bank transfers credit risk off its balance sheet without selling the loan itself, using contracts tied to individual firms, baskets, or broad indexes.
Netting Agreements
For derivative and securities financing exposures, master netting agreements collapse many trades into a single net obligation at default. To qualify for capital relief under Basel, these agreements must be legally enforceable in every relevant jurisdiction, even if the counterparty is insolvent or in bankruptcy.4Bank for International Settlements. Standardised Approach: Credit Risk Mitigation On-balance-sheet netting is the parallel idea: loans to a counterparty offset against deposits from that same counterparty, cutting the exposure the bank must hold capital against.
Diversification and Lending Limits
The plainest mitigation is not putting too many eggs in one basket. Federal lending limits enforce this mechanically at 15 percent of capital and surplus per borrower, with the additional 10 percent allowed only when the excess is fully secured by readily marketable collateral worth at least 100 percent of the overage at all times.3eCFR. 12 CFR Part 32 – Lending Limits Internal caps by sector and geography sit on top of that.
Capital Rules and Regulator Backstops
Minimum Capital Ratios
Basel III requires banks to hold minimum capital against risk-weighted assets. The floor for Common Equity Tier 1 (CET1), the highest-quality loss-absorbing capital, is 4.5 percent of risk-weighted assets.16Bank for International Settlements. Definition of Capital in Basel III – Executive Summary A mandatory capital conservation buffer of 2.5 percent, also composed of CET1, sits on top.17Bank for International Settlements. Buffers Above the Regulatory Minimum Added to the 8 percent total capital minimum, the effective total requirement reaches 10.5 percent.
U.S. rules turn these into capital categories. To be “well capitalized,” an FDIC-supervised institution needs total risk-based capital of at least 10 percent, Tier 1 of at least 8 percent, and CET1 of at least 6.5 percent. Fall below 8 percent total, 6 percent Tier 1, or 4.5 percent CET1 and the bank becomes “undercapitalized.” Below 2 percent tangible equity to total assets is “critically undercapitalized.”18eCFR. 12 CFR 324.403 – Capital Measures and Capital Category Definitions
Risk Weighting
Not every dollar consumes the same capital. Risk weighting assigns multipliers so riskier exposures require proportionally more. Under Basel’s standardized approach, top-rated sovereign bonds carry a 0 percent weight. Corporate loans to investment-grade firms might carry 50 or 75 percent, unrated corporates typically 100 percent, and retail exposures generally 75 percent.5Bank for International Settlements. Standardised Approach: Individual Exposures Higher weights mean more capital held, which is why unsecured consumer credit costs more than collateralized commercial loans.
Prompt Corrective Action
Regulators do not wait for a weak bank to recover on its own. Under prompt corrective action, an undercapitalized bank immediately faces restrictions on dividends and management fees.19eCFR. 12 CFR Part 324 Subpart H – Prompt Corrective Action As capital deteriorates, regulators can require a capital restoration plan, limit asset growth, and restrict executive pay. Civil money penalties escalate through three tiers: up to $5,000 per day for routine violations, up to $25,000 per day for reckless conduct or violations that are part of a pattern, and up to $1,000,000 per day for knowing violations that cause substantial losses.20Office of the Law Revision Counsel. 12 USC 505 – Civil Money Penalty
Stress Testing
The Federal Reserve’s annual stress test evaluates whether large banks can absorb heavy losses under hypothetical recession scenarios projected two years forward.21Federal Reserve Board. Federal Reserve Board Finalizes Hypothetical Scenarios for Its 2026 Stress Test The exercise estimates losses, net revenue, and resulting capital ratios under severe conditions such as sharply rising unemployment and a market downturn. Banks with large trading operations must also model the unexpected default of their biggest counterparty. If projected ratios fall below required minimums, the Fed can restrict capital distributions and require a revised capital plan before the bank expands lending.22Federal Reserve Board. Stress Tests Credit risk is treated as a system-level concern because a large institution’s failure pulls counterparties, depositors, and the wider financial system down with it.