Heanor (/ˈhiːnə/) is a town in the Amber Valley district of Derbyshire, England. It lies 8 miles (13 km) north-east of Derby and forms, with the adjacent village of Loscoe, the civil parish and town council-administered area of Heanor and Loscoe, which had a population of 17,251 in the 2011 census.

The name Heanor derives from the Old English hēan (the dative form of hēah) and ofer, and means "[place at] the high ridge". In the Domesday Book of 1086 it was recorded as Hainoure, with its entry stating:

6M In CODNOR and Heanor and Langley [in Heanor] and 'Smithycote' [in Codnor Park] 8 thegns had 7 carucates of land to the geld [before 1066]. [There is] land for as many ploughs. There are now 3 ploughs in demesne, and 11 villains and 2 bordars and 3 sokemen having 5½ ploughs. There is a church and 1 mill [rendering] 12d and 35 acres (140,000 m²) of meadow [and] woodland pasture 2 leagues long and 3 furlongs broad. TRE worth £4 sterling; now 41s 4d [£2.2] per year. Warner holds it.

Samuel Lewis's A Topographical Dictionary of England, published in 1848, states that Heanor parish "abounds with coal and ironstone, both worked extensively, the collieries alone affording employment to more than 2000 persons. The town is pleasantly situated upon an eminence, on the road from Derby to Mansfield. The principal articles of manufacture are silk and cotton goods, hosiery, and bobbinet lace, providing occupation to about 800 persons." The parish then covered 7,000 acres (2,800 ha) and was in the union of Basford and the hundred of Morleston and Litchurch, with Heanor town itself covering 1,500 acres (610 ha) with 3,058 inhabitants. The parish church, dedicated to St Mary, was "a very ancient edifice, with a lofty substantial tower, from which is an extensive view", though the dictionary noted there were also "places of worship for Baptists, Independents, Wesleyans, and Ranters".

Heanor Market Place developed in the 1890s after the break-up of the Heanor Hall estate by the Miller Mundy family of nearby Shipley Hall. The Market Place site had been part of Heanor Hall Park and the main focus of trading activity hitherto Tag Hill.

The parish of Heanor formed a local board of health in about 1850 to provide services in the town. In 1895, under the Local Government Act 1894, the board's area became an urban district. In 1899 Heanor Urban District was enlarged by the neighbouring parish of Codnor and Loscoe. The urban district remained until 1974, when it became part of a new non-metropolitan district of Amber Valley under the Local Government Act 1972. On 1 April 1974 the parish was abolished and it became an unparished area. In 1961 the parish had a population of 23,870. In 1984 three new civil parishes were created in Amber Valley, Heanor being within the civil parish of Heanor and Loscoe the other two parishes Aldercar and Langley Mill and Codnor). In 1987 Heanor and Loscoe Parish Council resolved to designate the parish a town, and so it is now governed by a town council headed by a town mayor.

Since 1984 Heanor has had three tiers of local government: Derbyshire County Council at county level, Amber Valley Borough Council at district level, and Heanor and Loscoe Town Council at parish level. Heanor falls into two single-member electoral divisions of the County Council, Greater Heanor and Heanor Central. Since the 2017 Derbyshire County Council election, both divisions are represented by members of the Conservative Party.

For Amber Valley Borough Council, Heanor and Loscoe civil parish divides into three electoral wards – Heanor East, Heanor West, and Heanor and Loscoe – which each elect two councillors. From 2014 to 2018, all six were from Labour, until the Conservatives narrowly took one seat in both Heanor East and Heanor West at the 2018 local elections, but fell short of taking a seat in Heanor and Loscoe. In the May 2019 local elections, Labour won 13 seats on the town council and the Conservatives 8.