The upstream division makes up the majority of ExxonMobil's revenue, accounting for approximately 70% of it. Across the upstream, geologists, engineers and scientists work tirelessly to explore and develop oil and natural gas using innovation and industry-leading technology. In 2021, ExxonMobil had about 30 billion barrels of oil and oil equivalents, as well as 38.1 billion cubic feet of natural gas.

In the United States, ExxonMobil's petroleum exploration and production activities are concentrated in the Permian Basin, Bakken Formation, Woodford Shale, Caney Shale, and the Gulf of Mexico. In Argentina, ExxonMobil holds 0.9 million acres, in Germany 4.9 million acres, in the Netherlands ExxonMobil owns 1.5 million acres, in Norway owns 0.4 million acres offshore, and in the United Kingdom 0.6 million acres offshore. In Africa, upstream operations are concentrated in Angola where it owns 0.4 million acres offshore, Chad where it owns 46,000 acres, Equatorial Guinea where it owns 0.1 million acres offshore, and Nigeria where it owns 0.8 million acres offshore.

Until the 2022 Russian invasion of Ukraine, ExxonMobil held 85,000 acres in the Sakhalin-I project through its subsidiary Exxon Neftegas. Together with Rosneft, it has developed 63.6 million acres in Russia, including the East-Prinovozemelsky field. In Australia, ExxonMobil held 1.7 million acres, including 1.6 million acres offshore.

After Russia's 2022 invasion began, though, ExxonMobil announced it was fully pulling out of both Russia and Sakhalin-I, and launched a lawsuit against Russia's federal government on August 30.

ExxonMobil markets products around the world under the brands Exxon, Mobil, and Esso. Mobil is ExxonMobil's primary retail gasoline brand in California, Florida, New York, New England, the Great Lakes, and the Midwest. Exxon is the primary brand in the rest of the United States, with the highest concentration of retail outlets located in New Jersey, Pennsylvania, Texas (shared with Mobil), and in the Mid-Atlantic and Southeastern states. ExxonMobil has stations in 46 states, just behind Shell USA and ahead of Phillips 66, lacking a presence only in Alaska, Hawaii, Iowa, and Kansas.

ExxonMobil's primary retail brands worldwide are Exxon, Esso, and Mobil, with the former being used exclusively in the United States and the latter two being used in most other countries where ExxonMobil operates. Esso is the only one of its brands not used widely in the United States. Outside of the United States, Esso and Mobil are primarily used, with Esso operating in 14 countries and Mobil operating in 29 countries and regions. In Japan, ExxonMobil had a 22% stake in TonenGeneral Sekiyu K.K., a refining company which merged with Eneos in 2017

ExxonMobil Chemical is a petrochemical company that was created by merging Exxon's and Mobil's chemical industries. Its principal products include basic olefins and aromatics, ethylene glycol, polyethylene, and polypropylene along with speciality lines such as elastomers, plasticizers, solvents, process fluids, oxo alcohols and adhesive resins.

Officially formed with ExxonMobil's 2022 corporate restructuring, and currently led by former General Motors president Dan Ammann, Low Carbon Solutions is the company's alternative energy division. The division intends to lower emissions in hard-to-decarbonize sectors such as heavy industry, commercial transportation, and power generation using a combination of lower-emission fuels, hydrogen, and carbon capture and storage. Low Carbon Solutions conducts research on clean energy technologies, including algae biofuels, biodiesel made from agricultural waste, carbonate fuel cells, and refining crude oil into plastic by using a membrane and osmosis instead of heat.

ExxonMobil publicly announced it would be investing $15 billion in what it deemed a "lower carbon future", and claims to be the world leader in carbon capture and storage. The company additionally plans that its Scope 1 and Scope 2 emissions will be carbon neutral by 2050. ExxonMobil additionally acquired biofuel company Biojet AS in 2022, and its Canadian subsidiary Imperial Oil is moving ahead with plans to produce a renewable diesel biofuel.

ExxonMobil is committed to reducing emissions. With our innovative energy solutions and our transformative research, we are creating a world where everyone has access to clean, reliable energy.