Montvale, N.J. ? The Great Atlantic & Pacific Tea Co., best known to grocery shoppers as A&P, says it has filed for Chapter 11 bankruptcy protection to deal with heavy debt and high costs.

The company, founded in 1859, says it will have access to $800 million in debtor-in-possession financing through JPMorgan Chase & Co. and that all of its 395 stores, which are located in eight states in the eastern U.S., are fully stocked and open for business.

Customer loyalty programs and other promotions will keep operating, the company said.

The Montvale, N.J., company says that it determined that it could not complete its turnaround plan without filing for bankruptcy protection. It blamed heavy debt, the costs of a work force that is 95 percent unionized, and tough competition that has sent customers to competitors such as discount superstores and warehouse clubs for its difficulties.

A&P listed about $2.5 billion in assets and $3.2 billion in liabilities in its bankruptcy filing. A hearing to approve the debtor-in-possession financing, which will allow the company to keep paying its employees and vendors, is set for today.

The filing was widely anticipated. The company’s stock price fell more than 67 percent on Friday, and trading was halted in the afternoon. Shares have traded between 86 cents and $13 in the past 52 weeks.

The company owns A&P, Waldbaum’s, The Food Emporium, Super Fresh, Pathmark and Food Basics grocery stores.

A&P is one of the oldest supermarket operators in the country. Its first store was in New York City and sold tea, coffee and spices.