Big D Oil Co.

Operating 49 stores in Colorado, South Dakota and Wyoming, the Big D chain offers a foodservice menu, car washes and express lubes. The company says it is committed to offering convenient stops, clean facilities and dependable service. Its staff works with trusted vendors and partners to supply its stores and ensure customers have access to the products they need while on the road.

For benchmarking purposes, store counts are as of Jan. 1, 2026.