The fine print: What's in your credit report?

Credit score
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If you're looking for scintillating reading material, your credit reports are not it. Yet these often-ignored documents are, increasingly, a must-read.

A quick review: Credit reports are a summation of your credit history and behaviors, as collected by the three major credit bureaus, Equifax, Experian and TransUnion. Lenders, insurers and prospective employers, among other parties, can take a look, making the information therein make-or-break for things, such as what interest you're offered on a credit card and whether you pass a prehire background check. Reports are also the basis for your credit score, that three-digit number in the 300-850 range (the higher the better) that lenders use as a measure of your creditworthiness to approve loans and set interest rates.

"Periodically checking the contents of your credit report is good financial hygiene," said Kareem Rogers, senior vice president of global consumer and business services for Equifax. "We think it's important for consumers to know where they stand as it relates to their credit history."

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It's not just knowing where you stand, but also making sure what's in the report is an accurate representation. A 2013 Federal Trade Commission study found that 20 percent of consumers identified errors on their reports that might affect their score, and 5 percent had an error significant enough that it could result in their paying higher loan rates.

Many of those are simple incidents of misreported information, said John Ulzheimer, president of consumer education for CreditSesame.com. "There's very likely a plausible, reasonable and logical explanation," he said.

Some are more sinister. Your report can also be a leading indicator of fraud or identity theft, said Rogers. That's where you'll see red flags such as accounts that aren't yours, and requests for new credit that you didn't initiate. Regular report reviews can help you spot those problems and take action against them sooner.

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Despite all the reasons to look, Americans tend to be fairly lax about reviewing their report. A 2013 TransUnion survey found that nearly one-third of Americans had never checked their credit report, and another 25 percent had not done so in the past year. In 2014, the Consumer Federation of America estimated that 51 percent of millennials had never checked their credit report.

"It can feel very overwhelming," said Gerri Detweiler, director of consumer education for Credit.com. Reports can easily top 20 pages in length, and aren't always easily decipherable. "There are going to be a lot of details on there, and it can take you a while to understand what they mean."

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That's where we come in. CNBC.com obtained a sample report from Experian. Mouse over the excerpts below to see bull's-eye markers on details experts say are important to review, and why.

First up, the personal information section. It's an easy one to gloss over, but possibly the most important one to assess for the sake of accuracy. "There are more than 230 million people with credit reports," said Rod Griffin, director of public education for Experian. Make sure you have the right one:

Before you get to the meat of the report—the detailed listings of each account—there is usually another short section, with a header of "Public Records." "Nothing good is ever in the public records section," said Ulzheimer. That's where you'll see score-scorching details like debts sent to collections, tax liens, civil court judgments, wage garnishments, foreclosures and bankruptcies. Worse, advocates say that a common error is for one of these black marks to appear in duplicate. "Ideally that section should be empty," he said.

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Account listings can take up most of your page count. Reports may break them out into those that are "potentially negative" and those "in good standing," or list them in some other fashion. However they're organized, check the details of each carefully:

If you're worried about identity theft, the inquiries section is one that merits close monitoring. It details who's been looking at your report:

At the end of the report, there's some fine print detailing consumers' rights related to credit reports, under the Fair Credit Reporting Act and other laws. Key among them: The right to dispute incomplete or inaccurate information.

Although filing a dispute is easy, having mistakes removed sometimes isn't. It's not unusual for a problem to resurface, said Ulzheimer. That happens because at many lenders, the department automatically feeding the credit bureaus data each month is not the same department handling dispute investigations, he said. Save any emails or letters promising a correction, and let the bureau know if you're experiencing dispute deja vu.

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If an error is particularly pervasive, you might complain to the government. "The consumer now has the ability to file a dispute with the [Consumer Financial Protection Bureau] regarding the accuracy of information on their credit reports," Ulzheimer said. "It's almost like bringing your older, stronger big brother to a fight."

This fine print also details other benefits:

Experts have differing thoughts on how often to check your report. Federal law entitles you to three free reports each year, one from each bureau, so you could request one every four months to regularly monitor for problems. Detweiler suggests people who haven't looked at their report recently (or ever) pull all three simultaneously. "That way you can compare," she said. There can be small variations in reported information among the bureaus, and it's not unusual to see an error on one that isn't reflected on the other two. Whichever method you opt for, mark the date on your calendar so you know when you're next eligible.

Timing also matters if you're looking at your report in anticipation of a major money move, like applying for a mortgage. In that case, aim to check your report at least three months in advance, and ideally, closer to six months out, said Griffin. That gives you time to address any potential problems, from errors to too-high balances that could affect your score. Disputing mid-application could hold up those mortgage proceedings, said Detweiler.

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Even if you want to check more often, it's rare that you'll need to pay for a copy of your report. Not only do state and federal laws often allow for more frequent pulls (see slide above), but sites including CreditSesame.com, CreditKarma.com and Credit.com also offer regular free access.

"There are so many ways to get free access to your credit report these days that I don't think you have to go on a diet and only pull it from time to time," said Ulzheimer. "There's really no reason not to look at your credit report once a month."