What Are the Three Main Credit Agencies?

Whenever you apply for credit, whether it is a new credit card or a loan, the lender is likely to run a check of your credit report. A credit report is a listing of all your credit and loan accounts, and it details the amount you owe to each creditor and your payment history. Lenders use the information in your report to determine a credit offer and terms. There are three main credit reporting agencies that perform this function.

Equifax

Atlanta-based Equifax has been in business for more than 100 years, making it the oldest, and most widely used, credit reporting agency. Equifax uses the formula developed by the Fair Isaac Corporation, also known as FICO, to determine your credit score. Equifax offers a credit-monitoring service that allows consumers to access the information contained in their credit reports and the opportunity to correct incorrect information or stop identity theft before it occurs.

Experian

According to Experian, the second-largest credit agency, the company maintains credit information on more than 215 million Americans. Headquarted in Costa Mesa, California, Experian also has satellite offices all over the U.S. and around the world. In addition to gathering data from lenders and credit card companies, as of 2010, Experian also offers rental payment history reports to landlords and other credit grantors. Experian also offers a monthly credit monitoring service for consumers. Experian calculates credit scores using the VantageScore system, which is a more general overview of your credit than the FICO score.

TransUnion

TransUnion is the smallest of the credit reporting agencies. Founded in 1968, it maintains information on about 500 million people in 25 countries worldwide. Like Experian, TransUnion calculates your credit score using VantageScore. TransUnion operates TrueCredit, a credit report monitoring service.

Credit Reports

Because the three major credit reporting agencies are competitors, the information contained in your individual reports from each company may vary. In addition, not all lenders report to all three bureaus. The 2004 Fair Credit Reporting Act granted consumers access to one free copy of their credit report from each company each year, and it is important that you check your report regularly to correct any discrepancies. In fact, it's estimated that your credit score can vary by as much as 40 points between credit agencies, so correcting any issues between companies can improve your overall credit picture.