Pitsea is a town and former civil parish in the Borough of Basildon, in south Essex, England. It comprises five sub-districts: Eversley, Northlands Park Neighbourhood (previously known as Felmores), Chalvedon, Pitsea Mount and Burnt Mills. It is part of the new town of Basildon.

During the creation of the new town of Basildon in the late 1940s and early 1950s, Pitsea, Vange and Laindon were considered as possible names for the new town. As Basildon village was central to the district, the town was eventually named Basildon. Before the new town regeneration, Pitsea itself was made up of unbuilt plot lands and was regarded as underdeveloped and run down.

The Cinema Museum in London holds extensive home movies from the Jefree family of Pitsea in the 1950s.

There is little known history about Pitsea, but its earliest recorded name is Piceseia in 1086 and is probably recorded as this in the Domesday Book. This has changed over the centuries to many variations of the name, including: Pichesey(e), Pikeseye, Pithesey, Petchesey(e), Pisseye, Pitchesey, Pissey, Pytsay, Pikeshay, Pitesey, Pitcheshey, Pytchey, Pitsey and finally to what it is now Pitsea. It is thought, however, that all the names are derived from the original meaning of Pics' Island, which refers specifically to the area now known as Pitsea Mount.

Chalvedon, which is part of Pitsea, has also been known under different guises. In its earliest form, it was known as Chauendona, meaning Calves Hill; this was first recorded in 1119. Other names include: Chaluedona, Chaluedene, Calueden and Callwedone, before it ended up being Chalvedon. Great Chalvedon Hall still stands, now operating as a pub, and was completed some time in the 16th century. During the building of the new town, Chalvedon became a housing estate in the west of Pitsea and the local secondary school had taken that name (now Basildon Academy - Chalvedon merged with Barstable School).

Pitsea was connected by the new London, Tilbury and Southend railway line in 1855. Next to the station is Cromwell Manor, previously Pitsea Hall, which dates from the 15th century. The arrival of the railway saw land around Pitsea bought and sold off piecemeal by companies like Protheroe and Morris of London who used tactics of free rail tickets and champagne auctions to convince East Londoners of the plotland dream. It was not until 1925 that planned development took place, when local entrepreneur Harold George Howard built The Railway Hotel (now demolished). He continued the development with The Broadway Cinema (closed in 1970 and reopened as a bingo hall which itself closed 2009 - demolished 2023) in 1930, along with Tudor Chambers and Anne Boleyn Mansions (home to TSB Bank). He also built Howard Crescent and Park which still exist to this day. Also in 1925, the locally famous Pitsea market first opened. In 1931 the parish had a population of 3414.

Further major development of Pitsea did not take place until the 1960s, when the new town redevelopment of Basildon took shape. Pitsea market was moved from its original location in Station Lane in 1969 to Howards Field, to make way for the construction of South Mayne. Pitsea was cut in half in the 1970s by the construction of the new A13 flyover (opened 1973), with Pitsea Mount separated from the rest of the town. In 1976, Pitsea's new town centre was opened along Northlands Pavement (previously Northlands Drive), with Sainsbury's being the anchor store along with a new office block called Pembroke House; it was quickly followed by the new Pitsea swimming pool (demolished 2013). In 1978, Tesco opened what was at the time the largest supermarket in Europe and would eventually become the first Tesco Extra store in 1997. Also, in 1978, Pitsea Market moved for a second time; it relocated behind the Railway Hotel and in front of the Sainsbury's supermarket (the second market place became a car park).

In 1981, the Pitsea Centre opened - a leisure centre and library opposite the former pool. A new leisure centre at Eversley opened in 1987. 1995 saw the opening of the Old Market Retail park on the second market place; part of this was destroyed by fire in 2006, to be rebuilt again in 2007. Sainsbury's supermarket moved outwards to Nethermayne, on the former sports ground of Carrera's cigarette factory.