Millions of Americans have mistakes on their credit reports, some of which are serious enough to lower credit scores and result in worse credit offers, a new government study finds.

As many as 42 million Americans have errors on their credit reports, according to a Federal Trade Commission study of around 1,000 participants and 3,000 credit reports released Monday.

"Errors in credit reports can cost you a loan, a competitive interest rate, a job, security clearance and insurance," said John Ulzheimer, president of consumer education at SmartCredit.com.

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Not all of these errors will impact your ability to get credit, however. In fact, only 2.2% of reports contained errors so serious that they could lead consumers to receive higher-priced credit than they deserve. But because the three biggest credit bureaus -- Experian, Equifax and TransUnion -- each maintain credit reports for about 200 million consumers, that error rate still means 10 million Americans are being denied loans or getting stuck with higher interest rates due to errors on their reports.

The Consumer Data Industry Association defended this 2.2% error rate, saying in a statement that overall, the report "shows that 98% of credit reports are materially accurate."

"[T]he measure of accuracy is tied to the question of when an error has a consequence for consumers, not just when a report contains an error that will have little or no impact on creditworthiness," the CDIA said.

A mistaken address won't lower a consumer's credit score, for example, while a misreported late payment may, said CDIA president Stuart Pratt.

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To avoid being deemed a higher risk than you really are, it's important to look at your credit report from all three major credit bureaus to make sure everything is correct. Free annual credit reports are available at annualcreditreport.com, yet fewer than one in five consumers check theirs, according to a separate study released by the Consumer Financial Protection Bureau.

"[C]onsumers should check their credit reports regularly. If they don't, they are potentially putting their pocketbooks at risk," Howard Shelanski, director of the FTC's Bureau of Economics, said in a statement.

But even if you do take the time to review your report and dispute an error, there's no guarantee of a quick fix.

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In some cases, the credit reporting agencies will rely on information provided by data furnishers like lenders and debt collectors even if it's wrong, said Ulzheimer. The CDIA's Pratt said credit reporting agencies thoroughly investigate disputes and data furnishers are required to do the same. And sometimes, what a consumer views as an error may not really be incorrect, he said. While some disputes can be frivolous, others are misunderstandings.

Consumer lawsuits filed against credit bureaus and data furnishers under the Fair Credit Reporting Act, which typically involve complaints about credit report errors, jumped to a record high of 2,249 last year, according to litigation tracking website WebRecon.