Santa Rosa’s Sonic Drive-In location has suddenly closed, with no explanation or future plans announced for the burgers and shakes joint.

Customers were surprised Sept. 3 to discover that the eatery — known for serving burgers, fries and many drink combinations including a Red Bull strawberry apricot slush and a cranberry limeade with Nerds candy — had closed its doors on 2245 Santa Rosa Ave.

The restaurant has been open at the site across from Santa Rosa Marketplace since 2022. Before it opened, the closest Sonic was in American Canyon. That location remains open for business.

Santa Rosa’s Sonic does not appear to have closed following any recent health inspections. According to the Sonoma County Department of Health Services Environmental Health Division, the restaurant passed a June 22 inspection.

The drive-in fast-food restaurant chain based in Oklahoma City has been owned by Inspire Brands since 2018.

Inspire, whose other brands include Arby’s, Baskin-Robbins, Buffalo Wild Wings, Dunkin’ and Jimmy John’s, did not immediately respond to questions about the closure, including how many employees were affected or if they will have the opportunity to transfer to other Sonic locations.

Inspire says it and its 2,500 franchisees operate more than 33,000 restaurants employing 650,000 workers worldwide. Some franchisees operate dozens of restaurants. Leawood, Kansas-based KBP Brands announced in February that it had purchased 78 Sonic Drive-In locations employing 1,600 people in eight states, making it the fourth largest Sonic franchisee.

Staff Writer Natalie Hanson reports on business and agriculture for The Press Democrat. She can be reached at natalie.hanson@pressdemocrat.com or at 619-665-5887.