WASHINGTON — The government’s newest regulator is ready to crack down on the nation’s large credit reporting and debt collection companies, proposing tough new oversight on two arcane financial groups that affect nearly all consumers.

The Consumer Financial Protection Bureau proposed to subject the companies to federal oversight for the first time as part of its broad authority to regulate firms outside the banking system.

By sending examiners to review their operations on a regular basis, the bureau hopes to spot problems before they arise at companies that book-end the consumer financial experience — firms that help determine who gets credit in the first place and those that pursue people unable to pay their bills.

“Debt collectors and credit reporting agencies have gone unsupervised by the federal government for too long,” Richard Cordray, the bureau’s director, said Thursday in announcing the effort.

The proposed rule, which is expected to be enacted in the next few months, was Cordray’s first major move since being installed by President Barack Obama last month in a controversial recess appointment.

Debt collection has been second only to identity theft in consumer complaints to the Federal Trade Commission in recent years. The bureau estimated that 30 million Americans have debts in the collection process.

One of the nation’s largest firms, Asset Acceptance, agreed to pay a $2.5 million civil penalty in January to settle a Federal Trade Commission lawsuit for misrepresentations in dealing with consumers, including failing to disclose when a debt was too old to be legally collected.

“It will improve things immensely because most debt collectors are operating in an either illegal or amoral way,” said Bill Bartmann, chief executive of debt collection company CFS II in Tulsa, Okla., who has been a longtime critic of some industry practices.

The three large credit reporting companies, Experian Information Solutions Inc., Equifax Inc. and TransUnion, have records on 200 million Americans and hold the key to getting a credit card or mortgage — and increasingly even a job.

Their practices have been mysterious to consumer advocates for years, and the new federal oversight should help reduce the number of mistakes on credit reports, said Ed Mierzwinski, consumer program director for the U.S. Public Interest Research Group.

“The CFPB is saying they should no longer be operating as a black box,” Mierzwinski said. “We should look inside the credit bureaus because they are gatekeepers to financial success, and we should see if their algorithms are fair to consumers.”

Credit reporting companies and debt collectors already fall under the bureau’s power to enforce consumer protection laws and enact new regulations. Cordray proposed to subject the largest of those companies to additional oversight because of their key role in consumer finance.