HollyFrontier, now operating as HF Sinclair Corporation, is an energy company based in Dallas, Texas. It specializes in crude oil refining and the wholesale marketing of refined petroleum products. The company was formed in 2011 through the merger of Holly Corporation and Frontier Oil and has since expanded through strategic acquisitions, including Petro-Canada Lubricants and Sonneborn.

HF Sinclair produces a variety of refined petroleum products, including gasoline, jet fuel, diesel, and specialty lubricants. The company also operates asphalt terminals and has a significant logistics infrastructure, with pipelines and terminals across the Mid-Continent, Southwest, and Rocky Mountain regions of the U.S. Its refining operations include multiple refineries, with a notable shift towards renewable fuel production at the Cheyenne refinery. HF Sinclair serves wholesale buyers across various sectors, providing essential products for transportation, industrial, and commercial markets.