ATLANTA — Inspire Brands, Inc. has completed its $2.3 billion acquisition of Sonic Corp. With Sonic now in the fold alongside Arby’s, Buffalo Wild Wings and Rusty Taco, Inspire is the fifth-largest restaurant company in the United States with more than 8,300 restaurants and annual systemwide sales in excess of $12 billion.

“We are thrilled to officially welcome Sonic to the Inspire family,” said Paul Brown, chief executive officer of Inspire Brands. “Sonic and its franchisees have created one of the most successful and distinctive brands in the restaurant industry. We look forward to helping further drive innovation and long-term growth at Sonic and across our growing family of brands.”

Along with the completion of the acquisition, Inspire said J. Clifford Hudson, former chairman and c.e.o. of Sonic, will serve as a senior adviser to Sonic until March 2019.

“This is an important and exciting milestone for Sonic,” said Claudia San Pedro, who was named president of Sonic in January and will take over as c.e.o. now that the transaction is complete. “Inspire’s commitment to strategic investments and culture of collaboration will significantly benefit our guests, team members, and franchisees. As part of the Inspire family of brands, Sonic is positioned for growth and to continue our 65-year track record of success.”