Nationwide Building Society is a British mutual financial institution, the seventh largest cooperative financial institution and the largest building society in the world with over 15 million members. Its headquarters are in Swindon, England. \nNationwide is the result of over a hundred mergers, the most notable of which are its merger with Anglia Building Society in 1987 and Portman Building Society in 2007. It is now the second largest provider of household savings and mortgages in the UK and has a 7.7% market share of current accounts. It was the highest ranked for customer service satisfaction amongst its high street peer group for the three months ending 31 March 2016.For the financial year 2015/2016, Nationwide had assets of around \u00a3208.9 billion compared to \u00a3331 billion for the entire building society sector, making it larger than the remaining 44 British building societies combined.It is a member of the Building Societies Association, the Council of Mortgage Lenders and Co-operatives UK. In 2016 Nationwide appeared 3rd in the \