The Big Four are the four largest professional services networks in the world: Deloitte, EY, KPMG, and PwC. They are the four largest global accounting networks as measured by revenue. The four are often grouped because they are comparable in size relative to the rest of the market, both in terms of revenue and workforce; they are considered equal in their ability to provide a wide scope of professional services to their clients; and, among those looking to start a career in professional services, particularly accounting, they are considered equally attractive networks to work in, because of the frequency with which these firms engage with Fortune 500 companies.
Ernst & Young Global Limited, trade name EY, is a multinational professional services partnership. EY is one of the largest professional services networks in the world. Along with Deloitte, KPMG and PwC, it is considered one of the Big Four accounting firms. It primarily provides assurance, tax, information technology services, consulting, and advisory services to its clients.
Deloitte Touche Tohmatsu Limited, commonly referred to as Deloitte, is a British multinational professional services network. Deloitte is the largest professional services network by revenue and number of employees in the world and is considered one of the Big Four accounting firms, along with EY, KPMG, and PwC.
Grant Thornton LLP is the American member firm of Grant Thornton International, the seventh largest accounting network in the world by combined fee income. Grant Thornton LLP is the seventh largest U.S. accounting and advisory organization. The firm operates 59 offices across the US with approximately 8,500 employees, 550 partners, and produces annual revenue in excess of US$1.9 billion.
RSM US LLP is an audit, tax, and consulting firm focused on the middle market in the United States and Canada and is a member of the global accounting network RSM International. It is the fifth-largest accounting firm in the United States and employs more than 17,000 professionals across 93 cities nationwide and in Canada. RSM US also maintains offices in India and El Salvador. Since 2012, RSM US has been headquartered in downtown Chicago.
RSM International, branded RSM since 2015, is a multinational network of accounting firms forming the sixth-largest accountancy professional services network in the world by revenue. RSM's member firms are independent accounting and advisory businesses, each of which practices in its own right and is unified as part of the network.
RSM Robson Rhodes LLP was a partnership of chartered accountants in the United Kingdom and Ireland. It was the UK member firm of RSM Global, the 6th largest network of professional accountancy firms in the world. With offices throughout the UK and Ireland, the firm offered auditing, consultancy and tax services to a wide variety of organisations in the private and public sectors.
RSM Tenon was a professional services firm based in the United Kingdom, which was listed on the FTSE SmallCap Index and part of RSM Global. The company was formed from the merger of the Tenon Group with RSM Bentley Jennison in December 2009.
BDO USA, P.C. is the United States member firm of BDO International, the fifth largest global accounting network with over $12.8 billion in revenue. In the US, BDO USA, P.C. is the sixth largest accounting and professional services firm. In 2023, BDO USA, P.C. became the first large national accounting firm to convert from a traditional limited liability partnership, to an entirely employee owned corporation. Due to this conversion, all employees are eligible to gain an equity stake in the company. BDO stands for Binder, Dijker, and Otte, the original founders of the firm. The company is currently headquartered in downtown Chicago.
Mazars is an internationally integrated partnership, specialising in audit, accounting and consulting group employing more than 47,000 professionals in more than 95 countries through member firms. With head offices in Paris, France, Mazars has a network of correspondent partners and joint ventures in a further 21 countries and is a founding member of the Praxity alliance, a network of independent firms.
Grant Thornton is the world's seventh-largest by revenue and sixth-largest by number of employees professional services network of independent accounting and consulting member firms which provide assurance, tax and advisory services to privately held businesses, public interest entities, and public sector entities. Grant Thornton International Ltd. is a not-for-profit, non-practising, international umbrella membership entity organised as a private company limited by guarantee. Grant Thornton International Ltd. is incorporated in London, England, and has no share capital.
FORVIS ranks among the U.S. top 10 public accounting firms, providing assurance, tax, and consulting services.
Vantis plc was an accountancy firm based in London, England, providing accounting, tax and business advice to owner-managed businesses, listed companies, not for profit organisations, high-net-worth individuals and other professionals. It was placed in administration on 29 June 2010 and promptly broken up, with the various offices and businesses being sold as going concerns.
Leonard Curtis is one of the largest independent firms in the UK specialising in corporate recovery, insolvency and business restructuring.
HLB International is a global network of independent advisory and accounting firms, comprising member firms in 157 countries. HLB International member firms offer audit, accounting, tax and business advisory services.
MNP is one of the largest full-service chartered professional accountancy and business advisory firms in Canada. MNP's head office is in Calgary, Alberta, and has offices from Vancouver Island to St. John's. MNP's 128 offices span across 9 out of 13 of the provinces and territories of Canada, as it does not have locations in Prince Edward Island, Yukon, Northwest Territories, and Nunavut. With 8,000+ employees, MNP is the third largest professional service firms in Canada by headcount.
Mitchell & Titus, LLP is an independent member firm of BDO Alliance USA and the largest accounting firm in the United States owned by a minority social group. Headquartered in New York City, the company provides professional services in assurance, tax, and advisory to Fortune 1000 companies, entrepreneurial enterprises, not-for-profit organizations, financial services firms, government entities, and high-net-worth individuals. Mitchell & Titus maintains six offices across six states in New York, New Jersey, Pennsylvania, Maryland, District of Columbia, and Illinois.
An accounting network or accounting association is a professional services network whose principal purpose is to provide members resources to assist the clients around the world and hence reduce the uncertainty by bringing together a greater number of resources to work on a problem. The networks and associations operate independently of the independent members. The largest accounting networks are known as the Big Four.
Baker Tilly International is a consulting and public accounting firm. It is currently the 9th largest accounting network in the world by revenue with 43,000 people in 700 offices across 141 territories with combined global revenues of $5.2bn. Baker Tilly operates geographically through four regions: Asia Pacific; Europe, Middle East and Africa; Latin America; and North America. Each region has a chair, appointed by the International Board, who leads an advisory council elected by members in that region.
Saffery is a firm of chartered accountants in the United Kingdom. It has nine offices across the UK as well as offshore. The firm acts for clients across a variety of sectors and provides accountancy, audit and assurance, personal and corporate tax, and corporate finance services.
US$$14 billion (2023) [2] 