Anglian Water is a water company that operates in the East of England. Anglian Water is regulated under the United Kingdom Water Industry Act 1991. It came into existence in 1989 as part of the partial privatisation of the water industry. It took on the water supply, sewerage and sewage treatment responsibilities of Anglian Water Authority. The remaining functions of the authority transferred to the newly formed Environment Agency.

Anglian Water supplies drinking water to all or parts of Bedfordshire, Buckinghamshire, Cambridgeshire, Essex, Lincolnshire, North Lincolnshire, North East Lincolnshire, Norfolk, Northamptonshire, Nottinghamshire and Suffolk.

Anglian Water provides drainage and sewerage to a wider area stretching from the Humber in the north to the River Thames in the south, including the River Great Ouse and a small part of Greater London around Upminster.