A negative credit rating is often considered undesirable to lenders and other extenders of credit for the purposes of loaning money or capital.

In the U.S., a consumer's credit history is compiled by credit rating agencies, more commonly referred to as consumer reporting agencies or credit bureaus. The data reported to these agencies are primarily provided to them by creditors and includes detailed records of the relationship a person has with the lender. Detailed account information, including payment history, credit limits, high and low balances, and any aggressive actions taken to recover overdue debts, are all reported regularly (usually monthly). This information is reviewed by a lender to determine whether to approve a loan and on what terms.

As credit became more popular, it became more difficult for lenders to evaluate and approve credit card and loan applications in a timely and efficient manner. To address this issue, credit scoring was adopted.

Credit scoring is the process of using a proprietary mathematical algorithm to create a numerical value that describes an applicants overall creditworthiness. Scores, frequently based on numbers (ranging from 300-850 for consumers in the United States), statistically analyze a credit history, in comparison to other debtors, and gauge the magnitude of financial risk. Since lending money to a person or company is a risk, credit scoring offers a standardized way for lenders to assess that risk rapidly and "without prejudice." All credit bureaus also offer credit scoring as a supplemental service.

Credit scores assess the likelihood that a borrower will repay a loan or other credit obligation. The higher the score, the better the credit history and the higher the probability that the loan will be repaid on time. When creditors report an excessive number of late payments, or trouble with collecting payments, the score suffers. Similarly, when adverse judgments and collection agency activity are reported, the score decreases even more. Repeated delinquencies or public record entries can lower the score and trigger what is called a negative credit rating or adverse credit history.

When a lender requests a credit score, it can cause a small drop in the credit score. That is because, as stated above, a number of inquiries over a relatively short period of time can indicate the consumer is in a financially difficult situation.

Consequences

The information in a credit report is sold by credit agencies to organizations that are considering whether to offer credit to individuals or companies. It is also available to other entities with a "permissible purpose", as defined by the Fair Credit Reporting Act. The consequence of a negative credit rating is typically a reduction in the likelihood that a lender will approve an application for credit under favorable terms, if at all. Interest rates on loans are significantly affected by credit history the higher the credit rating, the lower the interest while the lower the credit rating, the higher the interest. The increased interest is used to offset the higher rate of default within the low credit rating group of individuals.

In the United States, in certain cases, insurance, housing, and employment can also be denied based on a negative credit rating.

Note that is not the credit reporting agencies that decide whether a credit history is "adverse." It is the individual lender or creditor which makes that decision, each lender has its own policy on what scores fall within their guidelines. The specific scores that fall within a lender's guidelines are most often NOT disclosed to the applicant due to competitive reasons. In the United States, a creditor is required to give the reasons for denying credit to an applicant immediately and must also provide the name and address of the credit reporting agency who provided data that was used to make the decision.