A credit rating assesses the credit worthiness of an individual, corporation, or even a country. Credit ratings are calculated from financial history and current assets and liabilities. Typically, a credit rating tells a lender or investor the probability of the subject being able to pay back a loan. However, in recent years, credit ratings have also been used to adjust insurance premiums, determine employment eligibility, and establish the amount of a utility or leasing deposit.

A poor credit rating indicates a high risk of defaulting on a loan, and thus leads to high interest rates, or the refusal of a loan by the creditor.

Personal credit ratings

In the United States, an individual's credit history is compiled and maintained by companies called credit bureaus. Credit worthiness is usually determined through a statistical analysis of the available credit data. A common form of this analysis is a 3-digit credit score provided by independent financial service companies such as the FICO credit score. (The term, a registered trademark, comes from Fair Isaac Corporation, which pioneered the credit rating concept in the late 1950s.)

An individual's credit score, along with his or her credit report, affects his or her ability to borrow money through financial institutions such as banks.

In Canada, the most common ratings are the North American Standard Account Ratings, also known as the "R" ratings, which have a range between R0 and R9. R0 refers to a new account; R1 refers to on-time payments; R9 refers to bad debt.

The factors which may influence a person's credit rating are:

• ability to pay a loan
• interest
• amount of credit used
• saving patterns
• spending patterns
• debt

Corporate credit ratings

main: Bond credit rating The credit rating of a corporation is a financial indicator to potential investors of debt securities such as bonds. These are assigned by credit rating agencies such as Standard & Poor's, Moody's or Fitch Ratings and have letter designations such as AAA, B, CC. The Standard & Poor's rating scale is as follows: AAA, AA, A, BBB, BB, B, CCC, CC, C, D. Anything lower than a BBB rating is considered a speculative or junk bond. The Moody's rating system is similar in concept but the verbage is a little different. It is as follows: AAA, Aa1, Aa2, Aa3, A1, A2, A3, Baa1, Baa2, Baa3, Ba1, Ba2, Ba3, B1, B2, B3, Caa1, Caa2, Caa3, Ca, C.

Sovereign credit ratings

A sovereign credit rating is the credit rating of a sovereign entity, i.e. a country. The sovereign credit rating indicates the risk level of the investing environment of a country and is used by investors looking to invest abroad. It takes political risk into account.