Adrian Alastair Montague

Sir Adrian Alastair Montague (born February 1948) is a British solicitor and businessman. He has been the chair of Thames Water since July 2023. He was chairman of the insurance company Aviva from April 2015 to May 2020.

Early life Montague was born in February 1948. He earned a master of arts degree from Trinity Hall, Cambridge.

Career Montague began his career as a solicitor for Linklaters & Paines, where he worked from 1971 to 1994.

Montague was the chairman of Aviva from April 2015, succeeding John McFarlane, stepping down in May 2020.

In June 2023, Montague was appointed as chair of the Board at Thames Water and its parent company Kemble Water. In February 2024, Montague resigned as chair from Kemble Water but retained his position at Thames Water.

In a May 2025 appearance before the Environment, Food and Rural Affairs Select Committee, Montague claimed that Thames Water's lenders had 'insisted' on the payment of retention bonuses to the company's senior management. Montague later admitted in a letter sent to the committee following his appearance that he "may have misspoken" when he claimed that "creditors insisted on the management retention plan".

In a letter sent by Montague on behalf of Thames Water to the Environment, Food and Rural Affairs Select Committee following his appearance before the committee in May 2025, Montague confirmed that Thames Water had paid retention bonuses to senior executives at the company from a £3bn emergency loan provided by the company's creditors to stabilise the company's finances and prevent its collapse.

Personal life Montague has been married three times. He was married to Pamela Evans from 1970 to 1982; they had a son and two daughters. He was married to Penelope Webb from 1986 to 2009, and they had a son. In 2015, he was married for a third time, to Innes Daubeney.