One in 10 American consumers has no credit history, according to a study released Tuesday by the Consumer Financial Protection Bureau. (Tweet This) The research found that about 26 million American adults have no histories with national credit reporting agencies such as Equifax, Experian and TransUnion. In addition to those so-called credit invisibles, an additional 19 million have credit reports that are so limited or out of date that they are unscorable. In other words, 45 million American consumers are living without credit scores. Blacks and Hispanics were significantly more likely to be without a credit score, the study found, with a 15 percent rate of credit invisibility, compared to 9 percent for whites. Having a low income was another major predictor of whether someone had a credit score: census tract data showed that nearly 30 percent of consumers in low-income neighborhoods were credit invisible and another 15 percent had credit records that could not be scored. In upper-income neighborhoods, just 4 percent of consumers were credit invisible and an additional 5 percent were unscorable. "When consumers do not have a credit report, or have too little information to have a credit score, the impact on their lives can be profound," said Richard Cordray, director of the CFPB, in a call announcing the study. "And given that we found that consumers in low-income neighborhoods are more likely to be credit invisible or unscored, this may be limiting opportunities for some of the most economically vulnerable consumers."

Causes of credit invisibility

Younger adults were much more likely to be credit invisible or not have their credit record scored. More than 80 percent of 18 and 19 year olds were in that category, largely because they had had no time to establish a credit history, and that figure fell below 40 percent for those aged 20 to 24. (Tweet This) After age 60, the incidence of credit invisibility or unscorability rises again. (The increase was not due to stale information, however. The incidence of stale information among the elderly was lower than among consumers aged 25 to 29.) John Ulzheimer, president of consumer education at Credit Sesame, pointed to two reasons so many young American adults do not have credit scores. First, after the CARD Act passed in 2009, consumers under age 21 had to prove they had a job or a co-signer to get a credit card. The goal was to keep younger consumers from taking on credit card debt they could not repay, he said, "but if you are going to restrict people from getting credit, you are also going to restrict their ability to build a credit report." Use of prepaid debit cards are another factor, Ulzheimer said. Many of the problems associated with prepaid debit cards in the past, like fees that were high and not always easy to understand, have diminished, according to a study by The Pew Charitable Trusts. But prepaid card transactions do not help a consumer build a credit history. Read MoreStop paying for your credit score

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