Credit risk is the chance that a borrower does not repay a loan or fulfill a loan obligation. For lenders the risk includes late or lost interest and principal payment, leading to disrupted cash flows and increased collection costs. The loss may be complete or partial. In an efficient market, higher levels of credit risk will be associated with higher borrowing costs. Because of this, measures of borrowing costs such as yield spreads can be used to infer credit risk levels based on assessments by market participants.

Losses can arise in a number of circumstances, for example:

To reduce the lender's credit risk, the lender may perform a credit check on the prospective borrower, may require the borrower to take out appropriate insurance, such as mortgage insurance, or seek security over some assets of the borrower or a guarantee from a third party. The lender can also take out insurance against the risk or on-sell the debt to another company. In general, the higher the risk, the higher will be the interest rate that the debtor will be asked to pay on the debt. Credit risk mainly arises when borrowers are unable or unwilling to pay.

A credit risk can be of the following types:

Significant resources and sophisticated programs are used to analyze and manage risk. Some companies run a credit risk department whose job is to assess the financial health of their customers, and extend credit (or not) accordingly. They may use in-house programs to advise on avoiding, reducing and transferring risk. They also use the third party provided intelligence. Nationally recognized statistical rating organizations provide such information for a fee.

For large companies with liquidly traded corporate bonds or credit default swaps, bond yield spreads and credit default swap spreads indicate market participants assessments of credit risk and may be used as a reference point to price loans or trigger collateral calls.

Most lenders employ their models (credit scorecards) to rank potential and existing customers according to risk, and then apply appropriate strategies. With products such as unsecured personal loans or mortgages, lenders charge a higher price for higher-risk customers and vice versa. With revolving products such as credit cards and overdrafts, the risk is controlled through the setting of credit limits. Some products also require collateral, usually an asset that is pledged to secure the repayment of the loan.

Credit scoring models also form part of the framework used by banks or lending institutions to grant credit to clients. For corporate and commercial borrowers, these models generally have qualitative and quantitative sections outlining various aspects of the risk including, but not limited to, operating experience, management expertise, asset quality, and leverage and liquidity ratios, respectively. Once this information has been fully reviewed by credit officers and credit committees, the lender provides the funds subject to the terms and conditions presented within the contract (as outlined above).