She was the daughter of Peter Beckford, the Speaker of Jamaica's House of Assembly, and his wife, the former Bathsuba Hering.

[2] Her brother was William Beckford, who was Lord Mayor of London on two occasions.

From 1761 until her own death in 1791, she was a Lady of the Bedchamber to Charlotte of Mecklenburg-Strelitz, queen of George III of the United Kingdom.

By coincidence, her daughter-in-law Catherine died within a few days of her, while travelling from her home in Jamaica by sea to New York.

Elizabeth's elder son, Catherine's husband, who had inherited the earldom, died only a few weeks later.