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CardRatings.com recently conducted a poll asking readers whether they had ever found errors on their credit reports. Of 2,142 respondents, 1,568, or approximately three out of four, reported that yes, they have at one time or another found such an error, according to Amber Stubbs, the managing editor of CardRatings.com in Foster City, Calif.

With these findings, and the increasingly clever schemes of identity thieves, it shouldn't take much more to convince you to review your credit reports regularly and act promptly if you find errors in the reports.

Here are the steps you should take to dispute inaccuracies on your credit reports, which you are entitled to do under the Fair Credit Reporting Act.

1. Get your free credit reports. All consumers are allowed one free credit report every year from each of the three major credit reporting bureaus (Equifax, Experian and TransUnion), says Gail Cunningham, the vice president of public relations for the National Foundation for Credit Counseling in Washington, D.C. Go to AnnualCreditReport.com to request the free annual reports from each bureau. You can request all three reports at once or spread them out over different times of the year. (How's your credit? Get a free estimate with MSN Money's quiz.)

2. Check for errors and omissions. Review your credit reports for errors, Cunningham says. "A poor credit report impacts your ability to obtain credit, obtain insurance, rent an apartment or get a job. So it's very important to make sure the information is corrected if it's not."

It's also important that your credit reports don't shortchange your history. Don't see that gas credit card you paid off last year? Make a note to get it added. According to Rod Griffin, the director of public education for Experian, "An accurate and complete credit report is an important financial tool, and it can be treated just like a bank statement."

3. If there's an error, gather documentation. This step is critical. Take the time to assemble all the information you'll need to prove your case, such as copies of canceled checks and creditor statements.

If, for instance, a credit report shows that you still owe money on a bill that has been paid in full, include the statement that documents the zero balance, Cunningham says. "You're just stating the facts and making sure they understand your arguments," she adds.

4. Put it in writing. Contact the bureau whose report you believe to be inaccurate, giving your name, Social Security number and date of birth, Cunningham says. If you've moved recently, verify your previous address.

Write as if you were writing to a potential employer. Explain that you are disputing certain items, and give clear, factual reasons why. Include all the details of your case, such as account numbers, invoice numbers, check numbers and payment dates. Number your attachments to make it easy for the reader to find them. Make it clear what you want changed. Don't forget to sign your letter.

You can send your dispute to the credit reporting bureau by snail mail or online. If you use mail, Cunningham advises sending your letter by certified mail, with the return receipt add-on requested, so you can document that the bureau received the letter. As well, keep a copy of the confirmation of receipt.

However, it may be faster to send the dispute via the Internet. "You can dispute online. It's quick, it's secure, and it's the same process," Griffin says. "And you will receive confirmation the dispute was received."

At the same time, let the creditor know you're disputing the report, "so you're coming at this from both sides," Cunningham says. Include copies of the disputed charges and proof you've paid them, just as you did for the bureau.

5. Wait. Once the credit reporting bureau receives your dispute, its team must begin to investigate it immediately and must finish the investigation within 30 days. The bureau will notify the creditor initiating the report that it is investigating your dispute.

"That triggers another investigation on the part of the creditor reporting," Cunningham says. "The creditor has to investigate and confirm the accuracy."

If the creditor finds the information is inaccurate, it must notify all three major credit reporting bureaus so they can correct information in your files, she says.

When Experian receives a dispute, Griffin says, "we go back to the source of that information, typically a lender, and have them review records and either verify to us the information is reported correctly and should remain the same, or that they agree with the dispute and the information should be updated."

What if the lender doesn't respond? Griffin says, "If they don't respond in the mandated 30 days, the information will be deleted."

6. Get your results. In all likelihood, the dispute will be settled in much less time than 30 days. In most instances, just seven to 10 days are required, Griffin says. "The 30 days go back to the era when everything had to be mailed," he adds.

If you've built a good case in your dispute and you prevail, the credit reporting bureau must remove the inaccurate information from your report, Cunningham says.

But if the decision doesn't go your way and the investigation does not confirm your side of the dispute, you have another option. "You can ask the credit reporting agency to include a copy of the statement of dispute in your file, and that will go out with future credit reports," she says.

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This action may or may not make a difference to a future lender, Cunningham adds. But at least it shows you've done all you can to state your case.

Where to start

The best place to start the dispute process is on the credit reporting bureau's website. Here is the current contact information for each of the three major credit-reporting bureaus: