Loudwater is a private housing estate in the parish of Chorleywood,[1][2] separated from the latter by the River Chess, north of Rickmansworth, Hertfordshire and just to the east of Junction 18 of the M25 motorway.

[4] Archaeological finds of pottery, tiles and coins at Loudwater Farm indicate that it may be the site of a villa and water mill occupied by Germanic settlers in the 4th and 5th centuries AD.

[5] In the mid-19th century a paper mill was established in Loudwater using new technology developed by George Tidcombe.

[7] The present estate was built over approximately 20 years from 1939 on plots from the grounds of Loudwater House (see below) and now is a conservation area.

[10] As of April 2020[update] the Lord Lieutenant of Hertfordshire is Robert Voss CBE, a resident of Loudwater with his wife Celia.