The Embassy of the United States of America in London is the diplomatic mission of the United States in the United Kingdom. It is the largest American embassy in Western Europe and the focal point for events relating to the United States held in the United Kingdom.
There has been an American legation in London since John Adams was appointed the first minister in 1785. The ambassador's residence has been Winfield House since 1955. The embassy chancery in Nine Elms, Battersea, London, overlooks the River Thames and has been opened to the public since 13 December 2017, and was formally opened in January 2018. For much of the 20th century and into the 21st, the chancery was in Grosvenor Square, Westminster, London.