The firm of Agnew's dates back to 1817 when Thomas Agnew (1794-1871) entered into partnership with Vittore Zanetti, an Italian printseller and instrument, picture framemaker and gilder. The company was originally based in Manchester and Agnew became its sole proprietor in 1835 when the partnership was dissolved. Under his stewardship, the business expanded and became one of the country's leading printsellers and publishers while it also offered ancillary services (such as framing) and began to deal in pictures. Thomas' two sons, William (1825-1910) and Thomas (1827-1883), became partners in the business in 1851 when the firm became Thos. Agnew & Sons. The company flourished; a London branch in Waterloo Place opening in 1860 and they moved to a purpose-built Old Bond Street Gallery in 1877. By the end of the 19th century Agnew's had expanded from dealing in contemporary art to Old Master paintings and drawings, and became one of the major dealers in the international art market with offices around the world:
- Liverpool (1859-1909)
- Paris (1907-1914, 1919-[1926])
- Berlin (1908-1913)
- New York (1925-1931)
Following the market crash in 1932, Thos. Agnew & Sons became a limited company, closed the branch in Manchester and consolidated its activities in London. The company was able to survive the difficult years of the depression and the Second World War, and the business was supported by the W&T Agnew Syndicate which managed the expenditure on and rental from property (3-4 Albemarle Street and 42-43 Old Bond Street) with members of the Agnew family as shareholders. The company's fortunes picked up following the Second World War, and .... but move to contemporary art and began to struggle ... In 2008 Agnew's historic gallery in Old Bond Street was sold, and the company moved to a smaller gallery space in 35 Albemarle Street. In 2014 the firm passed to new owners, led by Cliff Schorer and Anthony Crichton-Stuart, who purchased the holding company of Thos. Agnew & Sons Ltd. from members of the Agnew family.
The following addresses were rented and/or owned by the firm from the early 1800s:
- Liverpool, 2 Duke Street
- Liverpool, Exchange Art Gallery, on the corner of Castle Street and Dale Street
- London, 3-4 Albemarle Street
- London, 5 Waterloo Place, Pall Mall
- London, 42-43 (previously 39) Old Bond Street
- Manchester, 14 Exchange Street
- Manchester, 94 Market Street, Manchester
- New York, 33 East 67th Street
