Angela Greiling Keane / Bloomberg News

WASHINGTON — The U.S. Postal Service’s announcement Thursday that it lost $5.2 billion in its third quarter added to calls for Congress to help the agency that’s supposed to run itself like a business and in many ways can’t.

The Washington-based service reported its 11th consecutive quarter of losses and said it may lose $15 billion in the fiscal year that ends Sept. 30. The loss was more than any quarterly net deficit in the past 12 months among companies in the Standard & Poor’s 500 and the Nasdaq Stock Market, according to data compiled by Bloomberg.

Sen. Susan Collins, a Maine Republican who is an author of a bill to alter the Postal Service, called the House’s inaction on a postal proposal “irresponsible.”

“Without legislation, the universal mail service that drives a trillion dollar mail industry and supports more than eight million jobs will be in jeopardy,” she said in an email.

The service said it still will make payroll for its workforce of 530,000 and pay suppliers when it temporarily runs out of cash in October.