Padiham (/ˈpædiəm/ PAD-i-əm) is a market town and civil parish on the River Calder, in the Borough of Burnley in Lancashire, England. It is located north west of Burnley, and north east of the towns of Clayton le Moors and Great Harwood. It is edged by the foothills of Pendle Hill to the north-west and north-east. The United Kingdom Census 2011 gave a parish population of 10,098, estimated in 2019 at 10,138.

Early forms of the name include "Padingham", with the last element probably from the Old English word hām, meaning home and ing in this sense meaning "of the". Its first is generally thought to be a personal name: Bede listed Padda as one of the priests who assisted Bishop Wilfrid in the late 7th century.

No prehistoric or Roman sites have been found in the built-up area. Padiham, though a name of Anglo-Saxon origin, is not recorded in the 1086 Domesday Book. Padiham was never a separate manor, its lands largely being held by copyhold tenants of the Manor of Ightenhill, a part of the Honour of Clitheroe. In 1258 there was a single free tenant, one Gilbert de Padiham. The Lord of Clitheroe had established a water-powered corn mill here by 1311. It remained for centuries as a market town, where produce from Pendleside was bought and sold. The town expanded and was redeveloped during the Industrial Revolution. The centre is now a conservation area.

Padiham's population peaked around 1921 at about 14,000, declining to 10,000 in the early 1960s and 8,998 at the time of the 2001 census. This reflected how people were moving to the south of England in search of work, after the decline in the traditional cotton, coal and engineering manufacturing industries.

Queen Elizabeth II and Prince Philip first visited Burnley, Nelson and the old Mullard valve factory at Simonstone near Padiham on their post-Coronation tour of Lancashire in 1955.

Padiham, once a township in the parish of Whalley, became a civil parish in 1866. An urban district covered the town from 1894 until 1974, but over this time, some rural areas mainly to the north became a new civil parish, Northtown, as part of Burnley Rural District. The Padiham Green area, hitherto part of Hapton, joined Padiham, with another small area following in 1935. Since 1974 Padiham has formed part of the Borough of Burnley. Initially part of an unparished area, a new Padiham civil parish was formed in late 2001, covering a similar area to the old urban district. A Town Council was instituted in 2002. Further boundary changes in 2004 saw the parish gain more territory in the south from Hapton.

Councillors for Padiham on Burnley Borough Council are elected to the Gawthorpe Ward, which covers most of Padiham, but not Gawthorpe Hall, with southern and eastern areas covered by Hapton with Park Ward. The two wards each elect three councillors, John Harbour and Alun Lewis of the Labour Party and Karen Ingham (Conservative) currently serving Gawthorpe and Joanne Broughton, Alan Hosker, and Jamie McGowan, all of the Conservatives in Hapton with Park. The parish is represented on Lancashire County Council as part of the Padiham & Burnley West division, represented since 2017 by Alan Hosker. The Parliamentary Constituency, Burnley, is currently represented by Oliver Ryan for the Labour Party.

According to the United Kingdom Census 2011, the parish had a population of 10,098, an increase from 8,998 in the 2001 census. The town forms part of a wider urban area, which had a population of 149,796 in 2001. A similar but larger, Burnley Built-up area defined in the 2011 census had a population of 149,422.