Description Britannia (formerly Britannia Building Society) provides financial services such as home mortgages, savings accounts, personal loans, and home and mortgage insurance. It also offers personal insurance and investments such as bonds, unit trusts, and individual savings accounts through an agreement with AXA UK's AXA Sun Life unit. Britannia has more than 200 branches throughout the UK. What began in 1856 as Leek and Moorlands grew to be the second largest building society in the UK before it was acquired by The Co-operative Bank in 2009 to create a so-called "super-mutual" financial institution.