Restaurant Brands International spent $1 billion to buy Firehouse Subs last year, and the fast casual’s numbers prove it was worth every penny.

The brand’s domestic same-store sales grew 15.2 percent year-over-year in the fourth quarter, and 23.4 percent on a two-year basis. As for 2021, Firehouse’s U.S. comps lifted 21 percent and 20.6 percent across two years.

The company’s comp sales and record-high $900,000-plus AUV drove systemwide sales of roughly $1.1 billion last year, compared to $872 million in 2020. More than 27 percent of those sales came through digital channels.

Firehouse completed 2021 with 1,213 units worldwide—net growth of 19 restaurants—including 1,164 domestically and 49 internationally.

“These impressive results are a testament to the strength of the brand, its unique menu offerings, its purpose-led public safety commitment, and its seasoned management team,” RBI CEO Jose Cil said during the company’s Q4 and 2021 earnings call. “It’s all of these elements that make us so confident in Firehouse Subs long-term growth and expansion opportunity.”

RBI is eager to shift Firehouse’s unit growth into “high gear in the coming years,” similar to what it’s done with Popeyes, according to Cil. 

Last year, the chicken leader experienced the highest number of openings since RBI acquired it in 2017. Popeyes finished 2021 with 3,705 restaurants globally—a net of 254 stores, or unit growth of 7.4 percent. That total breaks down to 2,754 U.S. locations (net of 146 restaurants) and 951 international outlets (net of 108 restaurants).

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Cil said the chain “signed more development agreements around the world than ever before,” with deals in India, the U.K., Saudi Arabia, Romania, and France, as well as further expansion in Mexico, the U.S., and Canada. In 2022, Popeyes continued its momentum with an agreement in South Korea, which Cil called one of the largest quick-service chicken markets in the world.

Although unit growth keeps rising, Popeyes U.S. same-store sales dropped 1.8 percent in Q4 year-over-year, and 8.2 percent on a two-year stack. Cil said ongoing labor challenges led to reduced operating hours, which impacted comps by roughly 1 percent. The CEO also noted the Popeyes Chicken Sandwich remains pressured by a number of competitors in the “chicken sandwich wars.”

Despite the sales decline, Cil said new and existing franchisees around the country remain enthusiastic because of the unit economics. 

“We are facing as we do with all brands in the U.S. and in more mature markets—there’s a lot of competition,” he said. “That’s part of the business. But we think we have a differentiated product with the chicken sandwich as well as our nuggets that were launched.”

“A lot of the innovation pipeline that we have on handheld chicken, we believe allows us to continue to grow long-term,” he continued. “The business investments in digital as well, we believe, are key drivers of growth for the brand in the U.S. in quarters and years to come. And we think there’s a tremendous opportunity here.”

Tim Hortons experienced positive net unit growth, as well. The coffee chain ended last year with 5,291 stores globally—a 6.9 percent increase year-over-year. That figure includes 3,949 restaurants in Canada (net of 13 stores) and 1,342 internationally (net of 329 stores).

Canada comps increased 11.3 percent in Q4, but slipped 0.6 percent on a two-year view. Still, it’s an acceleration from Q3, when comps increased 9.5 percent, but dropped 4.2 percent on a two-year basis.

“We are two years into our back-to-basics plan and continue to see encouraging proof points that our focus on elevating core quality, innovating for growth and modernizing the brand is positioning Tims well for long-term growth in Canada,” Cil said.

Overall, RBI finished the year with more than $10 billion in digital sales, mixing more than 30 percent. In Q4, digital at Tim Hortons Canada accounted for more than 33 percent of sales—an all-time high. Popeyes and Burger King’s U.S. markets saw digital mix of 16 percent and 9 percent, respectively.

Chief Operating Officer Joshua Kobza attributed digital improvement to growth in delivery, increases in mobile ordering, and continued traction of loyalty.

“2021 marked the first year we had loyalty across all our brands in home markets,” Kobza said. “While Burger King and Popeyes are earlier on in their journeys, during the year, Tim Hortons transitioned its loyalty program from one focused on building a strong user base to consistently driving comparable sales and as a result, saw the highest sales contribution from royalty to date.”