GREENSBORO, N.C. — Walgreen Co., the largest US drugstore chain, surged after renewing a contract to provide Express Scripts Inc. customers with prescriptions, ending a dispute that contributed to an 11 percent decline in the retailer’s quarterly profit.

Walgreen will become part of the network of pharmacies available to Express Scripts clients as of Sept. 15, the companies said Thursday in a statement. Terms weren’t disclosed.

The agreement ends a standoff that centered on reimbursement rates and caused Walgreen to lose customers to CVS Caremark Corp., Walmart Stores Inc. and other drugstore rivals. The contract with Express Scripts, which ended on Dec. 31, had generated $5.3 billion in annual sales for Walgreen.

Walgreen, based in Deerfield, Ill., jumped 11.79 percent to $34.62. Before Tbursday, the shares had slumped 28 percent from June 21, 2011, when it said it didn’t plan to renew its contract with Express Scripts.

The dispute revolved around reimbursement rates for 88 million prescriptions, or 10 percent of Walgreen’s pharmacy business. Walmart, CVS, and Rite Aid Corp. stepped up marketing to grab Walgreen’s prescription customers amid the impasse.

Express Scripts manages pharmacy benefit programs for private employers, unions and government health plans.