CST Brands, Inc. is an American publicly traded fuel and convenience retailer. It is the second-largest of its kind in North America, with 1,900 outlets in the U.S. and Canada. CST Brands had 2013 revenues of about $12.8 billion and made approximately $360 million in EBITDA. Stores are concentrated in the central and southwestern U.S. states and in eastern Canada. Corner Store is the firm's primary retail brand in the US and in Canada's English speaking provinces. In Canada's French speaking provinces, Dépanneur du Coin is the company's retail brand. In addition to convenience store retail sales, CST Brands also sells fuel under a number of licensed energy brands such as Valero, Exxon, Shell, and Phillips 66.

The company was created on May 1, 2013, when Valero Energy Corporation decided to spin off its retail operations in an effort to focus on refining. On August 6, 2014, CST Brands agreed to buy Lehigh Gas GP LLC, the general partner of Lehigh Gas Partners LP (LGP), from Lehigh Gas Corp in a cash and stock deal. CST Brands will also acquire the associated Incentive Distribution Rights of LGP. The deal closed on October 1, 2014 and LGP changed its name to CrossAmerica Partners LP, trading under the ticker symbol "CAPL".

On August 22, 2016, Alimentation Couche-Tard agreed to buy CST Brands in a deal worth $4.4 billion including net debt assumed. The transaction officially closed June 28, 2017.

CST operates over 1,000 Corner Store convenience store locations in the United States, including Texas, Louisiana, Arkansas, Oklahoma, New Mexico, Colorado, Wyoming, Arizona and California. On November 4, 2014 it was announced that CST Brands would acquire assets of Nice N Easy Grocery Shoppes, a New York-based company with over 30 company operated stores in its network. In November 2015, CST agreed to purchase Flash Foods from the Jones Company, a Waycross, Georgia-based convenience chain with 164 stores with retail fuel operations in Georgia and North Florida

In Canada, CST sells Ultramar fuels through over 840 retail sites in Quebec, the Atlantic provinces and eastern Ontario. Additionally, the company is one of the largest retail distributors of home heating oil in Eastern Canada. The network includes 80 card lock sites located along natural trucking routes or industrial parks that allow trucking and commercial fleets to buy fuel 24 hours a day.

CST employs approximately 12,000 people throughout the Southwestern United States and Eastern Canada, including over 400 at the CST Headquarters in San Antonio, Texas and over 250 at the CST Regional Office in Montreal, Canada.

Corner Store offers a range of products, such as snack foods, tobacco products, beverages and fresh foods, including its own brands: Fresh Choices sandwiches, salads and packaged goods; U Force energy drinks; Cibolo Mountain coffees (the United States); Transit Cafe coffee and bakery (Canada); FC bottled sodas, and Flavors 2 Go fountain sodas. Some of its Corner Store locations also provide in-store Subway sandwich shops.

Inside the stores, CST added 14 new items to its line of signature, private-label products, while also growing sales in Corner Store’s popular, fresh-baked goods, selling over 1.2 million whoopie pies and 4.6 million kolaches in 2013. Capitalizing on the popularity of its whoopie pies, the company outfitted a food truck to introduce more fans to the sweet treats at festivals and events in the markets CST serves.

CST operates in a highly competitive industry which includes 7-Eleven, Alimentation Couche-Tard Inc., Casey's General Stores, and The Pantry among the five largest chains. In 2014, CST had the third-largest chain with circa 1,900 sites.