QSR's franchised business model is a high-quality, capital-light, growing annuity that generates high-margin brand royalty fees from three leading brands: Burger King, Tim Hortons and Popeyes. The company nimbly navigated difficult market conditions in 2020 by assisting franchisees, while maintaining its long-term growth potential.
As the COVID-19 pandemic began, management undertook a series of steps to secure and strengthen the business. The company quickly bolstered safety procedures and shifted marketing spend to highlight the off-premise options available to customers, while supporting its franchisees with fee/cap ex deferrals and liquidity programs. Throughout the year, the company accelerated its digital investments by expanding its delivery footprint, modernizing its drive-thru experience, increasing mobile ordering adoption, and improving its loyalty programs.
While the company's sales were negatively impacted by the pandemic, comparable sales have already recovered or are well on their way to recovery. Burger King U.S. returned to growth in January; Tim Hortons improved to a high-single-digit decline in Canada during the fourth quarter, and Popeyes U.S. grew 16% in 2020. To accelerate the recovery at Tim Hortons in Canada, the company has committed additional funds to bolster its advertising, and support continued enhancements to its Tim's Rewards program.
We continue to believe each of Restaurant Brands' concepts will emerge stronger from this crisis as their business models are competitively advantaged in a socially distant and more budget-conscious consumption environment, and as the company continues to invest in drive-thru, delivery, and digital. We believe QSR's long-term unit growth opportunity is still intact, and we expect unit growth to return to its mid-single-digit growth rate this year. As investors begin to see the results of these efforts, and underlying sales trends at each of its brands continue to improve, QSR's share price should more accurately reflect our view of its business fundamentals.