WASHINGTON — The House passed a major consumer protection bill Monday that would compel credit bureaus to correct errors in consumers' files within 30 days, and for the first time would make banks and retailers legally responsible for supplying erroneous information to credit agencies.

The bill would also give consumers the right to a free copy of their credit reports each year.

The bill, approved by voice vote, "may be the most important consumer legislation considered by Congress this year," said Rep. Esteban E. Torres (D-La Puente), a key author of the bill.

The Senate passed its version earlier this year, and a conference committee is expected to prepare a compromise version for signing by President Clinton during the summer.

The final product would reform and update the Fair Credit Reporting Act, passed 24 years ago.

"Our country has changed dramatically . . . and the present state of technology and the volume of credit transactions have rendered the (act) dangerously ill-equipped to meet the needs of today's consumer," Torres said.

"We can no longer tolerate a system that denies employment to workers, prevents families from purchasing a mortgage or ruins thousands of credit histories because of errors in their files," he said.

Individual credit reports, which now cost as much as $8 each, would be available once a year without charge under the House bill. The Senate version calls for a $3 charge for a report.

Both versions of the legislation would impose new controls on the widespread use of credit files by businesses to investigate current or prospective workers. An employer would be barred from using credit files to investigate a worker or job applicant without the person's written permission.

The House bill also requires written approval by the consumer before a credit bureau can sell the consumer's records to companies engaged in direct marketing by mail. Firms in the credit card or catalogue business are anxious to get mailing lists of potential customers for their products.

The House bill also imposes new obligations for accuracy on banks, department stores and other retailers who provide information to credit bureaus. It also requires credit bureaus to establish special toll-free phone lines to handle calls from consumers seeking to correct errors in their credit reports.