Exxon Mobil Corporation is the world's leading publicly-owned energy company with a presence in some 200 countries and territories around the world.  ExxonMobil's business in the UK is conducted through individual operating companies.  These include:

Esso Exploration and Production UK Limited
Esso Petroleum Company, Limited
ExxonMobil Chemical Limited
Mobil North Sea LLC
Advanced Elastomer Systems Limited

In addition, specific international operations are stewarded from the UK by ExxonMobil subsidiaries including:

ExxonMobil International Limited
ExxonMobil Gas Marketing Europe Limited
ExxonMobil Marine Limited
International Marine Transportation Limited

The registered address for all of the companies above is:
ExxonMobil House
Ermyn Way
Leatherhead
Surrey KT22 8UX
United Kingdom