This is how Sonic increased sales by $1 billion during the pandemic, according to the drive-in chain's president

• Sonic increased sales by over 20% in 2020.
• The chain leveraged the drive-in to attract customers as dining rooms closed.
• Analysts also point to Sonic's broad menu as a reason for growth.
• See more stories on Insider's business page.

Sonic had one of its best years ever in 2020, with a business model that was in the perfect position to weather the pandemic – and even thrive during it.

Sonic sales boomed in 2020, growing 21% to $5.7 billion, according to Technomic and reported by Restaurant Business. The chain added over $1 billion in sales over 2019 figures.

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Sonic President Claudia San Pedro, who took over in 2018, attributed this success to the fact that Sonic is "an entire experience," she told Insider. "Some restaurants are a transaction to fill a function, but Sonic is about the experience." Customers can eat in their car at the drive-in, and order comfort food from a massive menu.

Drive-ins were perfect for 2020

Fast-food chains had a good year and grew drive-thru traffic substantially, but Sonic's drive-in left it uniquely positioned to benefit. Each Sonic "has in essence at least 25 drive-thru opportunities and eating spaces," San Pedro told Insider in a phone call.

Sonic's restaurants are set up like typical fast-food locations, with a dining room and drive-thru lane. The notable difference is its line of drive-in parking spots, each equipped with a speaker and menu board where customers can order.

"In a traditional drive-thru, there's only one place an order can be taken," Kalinowski Equity Research founder Mark Kalinowski previously told Insider. "That creates huge bottlenecks." Some chains, including Chick-fil-A and Starbucks, are solving the bottleneck problem with mobile ordering stations, while Sonic got around the issue with dozens of drive-in spots.

Sonic already had many of the features that consumers wanted more than ever last year, Kalinowski told Insider. Customers "couldn't eat in, but you could load up the family in the car and go to Sonic," he said.

San Pedro similarly emphasized how important the drive-in experience was during the pandemic. The drive-in can act as a drive-thru, where customers simply get their food and leave, but it gets people out of their homes during periods of work from home and school at home. For example, San Pedro said that Sonic saw a huge jump in families eating lunch together at the drive-in.

A menu with variety

Sonic has a huge menu, with fast food staples like burgers and chicken sandwiches, but also snack foods like onion rings and tater tots not tied to a specific meal time. Kalinowski said the broad menu with popular categories made Sonic a popular choice at a time when many competing options weren't available.

The drink menu in particular is massive, with a variety of sodas, lemonade, milkshakes, and other drinks with additional add-ins. San Pedro said that there are 1.3 million possible drink combinations at Sonic, and 25% of tickets are drink-only.

Ice cream sales were also a surprise area of growth, San Pedro said. They thought "ice cream might be more discretionary in a pandemic, but during stressful times you want comfort food," she told Insider. Most of Sonic's menu fits comfortably under a comfort food designation.

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