Mobil is a petroleum brand owned and operated by American oil and gas corporation ExxonMobil. The brand was formerly owned and operated by an oil and gas corporation of the same name, which itself merged with Exxon to form ExxonMobil in 1999.

A direct descendant of Standard Oil, Mobil was originally known as the Standard Oil Company of New York (shortened to Socony) after Standard Oil was split into 34 different entities in a 1911 Supreme Court decision. Socony merged with Vacuum Oil Company, from which the Mobil name first originated, in 1931 and subsequently renamed itself to Socony-Vacuum Oil Company. Over time, Mobil became the company's primary identity, which incited another renaming in 1963, this time to Mobil Corporation. Mobil credits itself with being the first company to introduce paying at the pump at its gas stations, the first company to produce jet aviation fuel, as well as the first company to introduce a mobile payment device, today known as Speedpass.

In 1998, Mobil announced it was merging with Exxon to form ExxonMobil, reuniting the two largest descendants of Standard Oil. The technicalities of the merger, which was completed on November 30, 1999, showed that Exxon bought Mobil, and Mobil shareholders received a payment of stock in Exxon. Mobil continues as a brand name within the combined company, as well as still being a gas station sometimes paired with its own store or On the Run. Mobil's brand name is primarily used to market motor oils, such as Mobil 1. The former Mobil headquarters in Fairfax County, Virginia, was used as ExxonMobil's downstream headquarters until 2015 when ExxonMobil consolidated employees into a new corporate campus in Spring, Texas.