Nationwide Building Society is a British mutual financial institution and the largest building society in the world. As of 2024, it serves over 16 million members and operates entirely for their benefit, without shareholders. The society was established through the consolidation of over 250 smaller UK building societies throughout the 20th century, making it one of the most significant mutual mergers in British financial history. Headquartered in Swindon, England, Nationwide offers a wide range of retail banking services including mortgages, savings accounts, current accounts, credit cards, personal loans, and insurance products. Nationwide is one of the largest cooperative financial institutions globally. As of June 2025, it reported total assets of £367.9 billion and employed 17,680 people. It operates 605 branches across the United Kingdom which is more than any other UK banking brand and it reaffirmed in 2024 its "Branch Promise" to maintain all branches until at least 1 January 2028. In October 2024, Nationwide completed its £2.9 billion acquisition of Virgin Money UK, adding over 6.6 million customers and expanding its customer base to more than 24.5 million. Wikipedia