Carole Middleton was born on 31 January 1955 at Perivale Maternity Hospital in Perivale, London, the daughter of Dorothy Harrison and Ronald Goldsmith; she is the older sister of IT recruitment multi-millionaire Gary Goldsmith. She spent her early years in a small house in Southall, attending the local state schools. She initially left school aged 16 but soon returned and got four A Levels. Although she wanted to be a teacher, Carole's parents "couldn't afford to put through college". She then worked as a secretary and can reportedly still do Pitman Shorthand. Brushing up her French, she got a job as ground staff at British Airways where she met flight dispatcherMichael Francis Middleton. At the time of their marriage, Carole was recorded as working as a stewardess. Michael's father, Captain Peter Middleton had been Prince Philip's co-pilot in 1962. The couple were married on 21 June 1980 at the Church of St James in Dorney, Buckinghamshire. Leeds-born Michael was the grandson of Olive Middleton – a member of the Lupton family who are described in the City of Leeds archives as being "landed gentry; a political and business dynasty".
In 1986, she and her family returned to West Berkshire, Bradfield Southend, after spending two-and-a-half years in Jordan. Her eldest daughter, Catherine, was aged four and attending the private preparatory college St Andrew's School, Pangbourne. In 1987, Middleton established Party Pieces, a company which began by making party bags and which now sells party supplies and decorations by mail order. In 1995, under the joint leadership of Carole and Michael, the firm's growth necessitated its headquarters be moved to a range of farm buildings at Ashampstead Common. The family's wealth is the result of the success of their business combined with the trust funds inherited from Olive Christiana Middleton, whom the BBC reported in 2011 as being Michael Middleton's aristocrat grandmother. This wealth has resulted in the Middletons being reported to be multi-millionaires. Carole and her husband Michael own Bucklebury Manor, in Bucklebury, West Berkshire – a substantial Grade II-listed Georgianmanor house set on over 18 acres. The Middletons' grandson Prince George spent his first few weeks at Bucklebury Manor. In 2002, Carole and Michael Middleton bought "with cash" a flat in Chelsea, London, in which their children lived after completing their university studies. The goldchevron on the coat of arms taken out by her husband Michael is in reference to Carole's maiden name of Goldsmith.
Carole's maternal great-grandfather was Durham coal miner John Harrison. Her paternal great-great-grandfather was John Goldsmith, a labourer and brick maker from Hoxton in the East End of London.