The company was established in 1714 as the Union Fire Office, with the first meeting being held at the Amsterdam Coffee House in Threadneedle Street, London. The company’s first claim was paid out in December of the same year on a fire at the Dolphin Tavern in Mark Lane, London.
According to a 1735 prospectus, the aims of the company were “to insure merchandises, goods, wares, utensils in trade, household furniture and such-like things; except plate and pictures, as also glass and china ware, all not in trade; also ready money, jewels, books of account, tallies, writings, barns, ricks and stacks of corn, hay and straw.”
Shortly after its formation, the company entered into an agreement with the Hand-in-Hand Fire Office in which Hand-in-Hand would insure only buildings and Union only contents. This situation continued until 1805 when Union extended its business to include houses and other buildings.
In 1813 the company started to offer life assurance and extended what had been a primarily London-based business to the rest of the UK and overseas. In the same year, the company dropped the “fire” part of its name and variously described itself in advertisements and in its policies as the Union Assurance Office, the Union Assurance Company, the Union Society and the Union Assurance Society.
Union Assurance continued to grow and in 1888 it extended its overseas and fire business. By 1891 the company was also transacting life business on the continent and in 1904 an accident department was established following the acquisition of the Scottish Alliance Insurance Company.
In the wake of the disastrous San Francisco earthquake in 1906, the company paid out to policy holders total claims of over £800,000. The company struggled to absorb such a large pay out and was subsequently acquired by the Commercial Union Assurance Co. the following year.