Luton (/ˈluːtən/ ^ⓘ) is a town and borough in Bedfordshire, England. The borough had a population of 225,262 at the 2021 census.

Luton is on the River Lea, about 32 miles (50 km) north-west of London. The town's foundation dates to the sixth century as a Saxon settlement on the river, from which Luton derives its name. Luton is recorded in the Domesday Book as Loitone and Lintone. One of the largest churches in Bedfordshire, St Mary's Church, was built in the 12th century. There are local museums which explore Luton's history in Wardown Park and Stockwood Park.

Luton was once known for hatmaking and became a centre for the British motor industry with the establishment of the Vauxhall Motors factory in 1905. Car production at the Luton plant continued until 2002. Thereafter, the site focused on commercial vehicle manufacturing which in turn came to an end in 2025. The head office of Vauxhall Motors is located in the village of Chalton, on the northern edge of the borough. London Luton Airport opened in 1938 and is now one of Britain's major airports, with three railway stations also in the town. The University of Bedfordshire was created from a merger with the University of Luton; two of its campuses are in Luton. Since 1997, Luton Borough Council has been a unitary authority, performing all local government functions in the borough.

Luton Town Football Club, nicknamed the Hatters, due to the town's connection to hatmaking, has had several spells in the top flight of the English league as well as a Football League Cup triumph in 1988. They play at Kenilworth Road, their home since 1905; planning permission for a new larger stadium was approved in 2019. Luton International Carnival, the largest one-day carnival in Europe, is held on the day before the last Monday in May; the Saint Patrick's festival is held on the weekend nearest to Saint Patrick's Day as there is a large Irish community in Luton. The town also has a large Pakistani community which, along with the Irish, were attracted to employment at the Vauxhall car plant. Luton Hoo is an English country house, estate and Grade I listed building originally designed by Scottish architect Robert Adam but later transformed to the designs of Robert Smirke.

Luton is believed to have been founded by the Anglo-Saxons sometime in the 6th century. Its name first appears in the 8th century as Lygetun, meaning "town on the River Lea".

The Domesday Book records Luton as Loitone and as Lintone. Agriculture dominated the local economy at that time, and the town's population was around 700 to 800.

In 1121 Robert, 1st Earl of Gloucester started work on St Mary's Church in the centre of the town. The work was completed by 1137. A motte-and-bailey castle which gives its name to the modern Castle Street was built in 1139 but demolished by 1154.

The hat making industry began in the 17th century and became synonymous with the town.