Andrew Pears moved from Cornwall to London in the late 1780s, opening a barber’s shop after training as an apprentice barber. Once in London he worked on refining a gentler soap formula than contemporary options, also working to remove impurities. He eventually settled on a product in 1807, which was the world’s first transparent soap. He showed his design to a Mr. John Watson, who took the soap into production and attempted to patent the design in his name, without crediting Pears. However, in 1809 this went to trial and Andrew Pears won his claim to a unanimous Jury decision that December.

In 1835, Andrew Pears’ grandson Francis Pears joined the business, creating A. & F. Pears. Andrew retired in 1838. The company continued to grow whilst remaining in the family, with Francis’ son joining in 1868 – the same year production moved to Isleworth. In 1851, the company's soap was awarded the prize medal for soap at The Great Exhibition.

Thomas James Barratt joined the company in 1864, marrying Francis Pears’ eldest daughter - Mary Frances - within a year and then becoming a partner of the company. Barratt has been referred to as ‘the Father of modern advertising’ due to his work at Pears, which also made the brand a household name. Thanks to him, Pears was the world’s first registered brand, and today remains the world’s oldest continuously existing brand. Barratt had many advertising tactics, including:

- filling newspaper advertising space with the brand name to get around rules on illustrated advertisements,

- celebrity endorsements – such as Lillie Langtry,

- acquiring works of art to use in advertisements, most famously John Everett Millais' painting, ‘A child’s world’, which was renamed ‘Bubbles’,

- utilising ‘stunts’, such as bulk buying French coins – which at the time could be accepted as tender in England – and defacing them with the Pears’ branding before placing them back into circulation. This has anecdotally been marked as the cause of coin defacing being outlawed, but evidence to support this cannot be found.

However, some of Pears’ advertising was racially charged, using language and imagery that connected cleanliness with whiteness, or as ‘The white man’s burden’. Some adverts even depicted the product being used to change skin colour, as is the case in one advert where a white child is washing a black child whose skin magically seems to become white. During a period of public criticism of an advertising campaign by Dove in 2017, the media and the general public referenced Pears’ advertisements as a comparison due to the similar language and imagery.

Pears became part of the Lever Brothers in 1914, which later became Unilever. Their strong marketing continued despite the take-over, continuing to produce their annuals until 1925 and introducing a ‘Miss Pears’ competition to be the face of the brand in 1958 which ran until 1997. The ‘Pears Cyclopaedia’, launched for Queen Victoria’s Diamond Jubilee in 1897, continued to be published until 2017.

Pears is still used by Unilever as a brand name, with production moving to India in 1992 for an international market under Hindustan Unilever. The product was relaunched in the UK in 2016, with the addition of body wash and hand soap and a marketing campaign focussed on their heritage and age, at over 200 years old.