Leading global auditing firms are important partners for many FDI businesses in Vietnam. Law on Independent Auditing No. 67/2011/QH12FDI enterprises, credit institutions, insurance companies, and public companies are required to obtain this certification. audit by independent auditing firm They are qualified to practice. Therefore, choosing an auditing firm with an international network not only helps meet legal regulations but also enhances reputation and facilitates the business's fundraising process.
This article compiles a list of the world's leading auditing firms, analyzing the strengths of the Big 4 (Deloitte, PwC, EY, KPMG) along with six other reputable international auditing firms, and outlining suitable selection criteria for FDI businesses and foreign investors. The content is compiled from the practical perspective of MAN – Master Accountant Network, an auditing, accounting, and tax consulting firm with over 30 years of experience in the Vietnamese market.
A summary of key features of the world's leading auditing firms.
- The world's leading audit firms are the group of audit firms with the largest revenue, office networks, and number of employees globally, led by the Big 4 (Deloitte, PwC, EY, KPMG).
- Used for auditing financial statements, providing tax advice, and supporting financial transactions for multinational corporations.
- This applies to FDI enterprises, listed companies, and multinational corporations that need to report financial statements that meet international standards.
- This is necessary when a business is subject to mandatory auditing by law, when raising international capital, going public, or conducting cross-border mergers and acquisitions.
- Main legal basis: Law on Independent Auditing No. 67/2011/QH12, Article 37 stipulating the subjects required to undergo auditing.
What criteria are used to rank the world's leading auditing firms?
There is no table ranking of auditing firms This is the only official benchmark for the world's leading auditing firms. Industry research organizations typically rely on four main criteria: annual global revenue, number of employees, network coverage across countries, and the diversity of services offered, including auditing, tax, advisory, and legal services.
Based on these criteria, the Big 4 consistently lead, followed by the mid-tier group of six other leading global auditing firms. The mid-tier group is smaller than the Big 4 but still holds a significant global presence, making it suitable for medium-sized businesses and niche markets.
The world's four largest auditing firms: Who are the names in the Big 4?
The Big 4 largest auditing firms in the world. This includes Deloitte, PwC, EY, and KPMG. Four major auditing firms This provides auditing servicesProviding advisory, tax, trading, and risk management services in most major global financial markets, serving the majority of Fortune Global 500 corporations.
Deloitte
Founded in 1845 in London by William Welch Deloitte, Deloitte currently has its global headquarters also in London. It is the largest of the Big 4 auditing firms in terms of both revenue and personnel, operating in over 150 countries with approximately 460,000 employees.
Global revenue for fiscal year 2024 is projected at approximately $67.2 billion, with audit and assurance contributing around $21 billion, the highest among the Big 4 firms. Deloitte's strength lies in its ability to handle complex multinational client structures thanks to its extensive network and diverse service portfolio.
PwC (PricewaterhouseCoopers)
PwC was formed in 1998 from the merger of Price Waterhouse and Coopers & Lybrand, headquartered in London. The firm has over 370,000 employees and a presence in approximately 149 countries. Global revenue for the fiscal year ending June 30, 2024, reached $55.4 billion, with the Assurance segment contributing approximately $19.5 billion.
PwC serves approximately 861 companies on the Fortune Global 500 list, and is investing heavily in AI technology and digital audit platforms to meet the increasingly stringent ESG reporting requirements of international investors.
EY (Ernst & Young)
EY was formed in 1989 from the merger of Ernst & Whinney and Arthur Young, and is headquartered in London. The firm has approximately 393,000 employees and operates across four main regions: Americas, EMEIA, Asia Pacific, and Japan.
Global revenue for fiscal year 2024 is projected to reach approximately $51.2 billion, with the Assurance and Tax segment recording the strongest growth rate during the 2023-2024 period. EY is highly regarded for its ability to support cross-border mergers and acquisitions and business valuations.
KPMG
KPMG was formed in 1987 from the merger of Peat Marwick International and Klynveld Main Goerdeler, headquartered in Amstelveen, Netherlands. The firm has approximately 275,000 employees and operates in 145 to 150 countries.
Global revenue for the fiscal year ending September 30, 2024, reached approximately $38.4 billion, with the Audit segment growing by 6.21 TP3T to $13.4 billion and the Tax & Legal segment growing by 9.61 TP3T to $8.7 billion. KPMG has the advantage of serving both medium-sized enterprises and large corporations thanks to its deep expertise combined with an international network.
Besides the Big 4, what are the other six top auditing firms in the world?
Besides the four largest auditing firms in the world, the mid-tier group of six international auditing firms still holds a significant position, particularly suitable for medium-sized businesses and transactions with more modest capital sizes.
BDO Global
BDO Global has revenues of $11.8 billion, approximately 97,200 employees, and is headquartered in Zaventem, Belgium. It is the world's fifth-largest auditing firm, leading the mid-tier group with 1,800 offices in 164 countries. BDO focuses on serving medium-sized enterprises (SMEs), with a more flexible culture and a more personalized approach compared to the Big 4.
FPT
RSM has revenues of $8 billion, approximately 57,000 employees, and is headquartered in London. The firm has 830 offices in 120 countries and holds a particularly strong position in the US market. RSM focuses on technology-based solutions and personalized audit services for small and medium-sized clients.
Grant Thornton International
Grant Thornton has revenues of $7.2 billion and approximately 68,000 employees, headquartered in London. The firm utilizes its proprietary Voyager suite of audit tools to standardize processes across its network and has built a consistent audit quality monitoring system across its member markets.
Baker Tilly International
Baker Tilly recorded revenue exceeding $4.6 billion, a 131% increase year-over-year, with approximately 39,000 employees and headquarters in London. Its network spans 145 countries, with strengths in specialized services for private equity, the public sector, and the real estate and construction industries.
Crowe Global
Crowe Global has revenues of $4.4 billion, approximately 42,000 employees, and is headquartered in New York. The company owns more than 200 subsidiaries in 130 countries, focusing on serving small and medium-sized businesses with expertise in healthcare, financial services, and manufacturing.
Nexia International
Nexia International concludes the list with revenues of $4 billion, approximately 26,000 employees, headquartered in London, and present in over 120 countries. The firm builds its auditing services on industry expertise combined with local market insights, serving the healthcare, technology, retail, and finance sectors.
Comparison table of the world's leading auditing firms
The table below summarizes the size of the world's top ten auditing firms by revenue, staff, and country coverage, providing businesses with an overview before choosing a partner.
| Company | Headquarters | Global revenue | Human Resources | Number of countries |
| Deloitte | London, England | ~67.2 billion USD | ~460.000 | 150+ |
| PwC | London, England | ~55.4 billion USD | ~370.000 | 149 |
| EY | London, England | ~51.2 billion USD | ~393.000 | 150+ |
| KPMG | Amstelveen, Netherlands | ~38.4 billion USD | ~275.000 | 145-150 |
| BDO Global | Zaventem, Belgium | ~11.8 billion USD | ~97.200 | 164 |
| FPT | London, England | ~8 billion USD | ~57.000 | 120 |
| Grant Thornton | London, England | ~7.2 billion USD | ~68.000 | 140+ |
| Baker Tilly | London, England | ~4.6 billion USD | ~39.000 | 145 |
| Crowe Global | New York, USA | ~4.4 billion USD | ~42.000 | 130 |
| Nexia International | London, England | ~4 billion USD | ~26.000 | 120+ |
What criteria should FDI businesses use to select a suitable international auditing firm?
According to Official Letter No. 1339/BTC-CĐKT dated January 24, 2014, from the Ministry of Finance, foreign-invested enterprises These entities are on the list of those required to have their annual financial statements audited. If the tax return does not include the audit report, the tax authorities have the right to refuse acceptance and request that it be supplemented.
Network compatible with parent company: Choose an auditing firm with a presence in the country where the parent company is headquartered to ensure consistency in consolidated financial reporting standards.
In addition to network factors, businesses should consider the following three criteria when choosing an audit partner:
- Industry experience: An auditing firm that has previously served businesses in the same manufacturing, trading, or service sector will have a proper understanding of the nature of the transaction and the specific risks involved.
- Ability to run two reporting standards in parallel: It meets both Vietnamese Accounting Standards (VAS) and International Financial Reporting Standards (IFRS) as required by the parent company.
- Cost-effective to scale: The fees charged by the Big 4 are typically significantly higher than those of mid-tier firms, requiring a balance between budget and the practical demands of shareholders.
From the perspective of MAN – Master Accountant Network, after many years of working with FDI enterprises in Vietnam, choosing an auditing firm is not just about global brand. The capabilities of the local team, their understanding of Vietnamese tax and accounting regulations, are the decisive factors in the quality of the audit and the level of risk when settling taxes at the end of the year.
Case Study: How do FDI manufacturing companies choose international network auditing partners?
Background
Company Y, a Japanese-invested manufacturer of industrial equipment, has annual revenue of approximately $40 million and operates in Dong Nai province. The parent company in Japan requires consolidated financial statements to be prepared according to IFRS standards, while the subsidiary in Vietnam must still prepare reports according to VAS standards for submission to the tax authorities.
Handle
Following advice from MAN – Master Accountant Network, the company took three steps: (1) reviewing the consolidated financial reporting requirements from the parent company to determine the standards and deadlines for submission; (2) selecting an auditing firm with a network of affiliations in Japan, ensuring that the audit data in Vietnam is directly accepted by the parent company; (3) standardizing accounting records according to VAS in parallel with IFRS before the audit season, avoiding last-minute adjustment entries.
The measured results
- The time required to complete the annual financial statement audit has been reduced from 25 days to 14 days.
- The number of adjusting entries arising during the audit decreased by more than 60% compared to the previous year.
- The audit report was accepted by the parent company in Japan on the first review basis, with no further clarification required.
Expert opinion: Common risks faced by FDI businesses when choosing international auditing firms.
Experts at MAN – Master Accountant Network, with over 30 years of experience in tax consulting and auditing in Vietnam, point out four main risks that FDI businesses often face:
- Risk 1: Choosing based on brand name while ignoring the capabilities of the local team: Many businesses prioritize the Big 4 firms but fail to thoroughly vet the auditors directly responsible. When the local team lacks experience with the specifics of the industry, audit times are extended and costs exceed initial estimates.
- Risk 2: Inconsistency in reporting standards between parent and subsidiary companies: When the parent company requires IFRS but the subsidiary only prepares documents according to VAS, the auditing firm has to spend extra time comparing the data, leading to the risk of discrepancies in consolidated figures and delays in reporting to foreign shareholders.
- Risk 3: Lack of preparation of accounting records before the audit season: Disjointed documentation, a lack of debt reconciliation statements, or asset inventory records can prolong audits, sometimes leading to qualified audit opinions, directly impacting loan applications or reports to investors.
- Risk 4: Ignoring long-term costs when switching audit firms: Moving from a Big 4 firm to a mid-tier firm, or vice versa, mid-term can lead to the loss of historical audit data and incur additional costs for reviewing opening balances. Businesses should plan a long-term audit strategy rather than choosing audits on a year-by-year basis.
Conclude
Leading global auditing firms differ not only in revenue size and number of personnel, but also in their approach to different client groups, from listed corporations to medium-sized enterprises. Understanding each firm's strengths, comparing them with the parent company's reporting requirements and current legal regulations in Vietnam, will help FDI businesses avoid unnecessary risks when choosing an auditing partner.
MAN – Master Accountant Network is a tax, accounting, and auditing consulting firm with a team of experts boasting over 30 years of practical experience and a deep understanding of tax risk management in Vietnam. We support FDI businesses, domestic businesses, and individuals in preparing audit documents, selecting suitable audit partners, and resolving issues arising during the tax settlement process. For specific advice tailored to your business, please contact MAN – Master Accountant Network.
Service contact information at MAN – Master Accountant Network
- Address: No. 19A, Street 43, Tan Thuan Ward, Ho Chi Minh City
- Mobile/Zalo: 0903 963 163 – 0903 428 622
- E-mail: man@man.net.vn
- Google Business Profile: View MAN – Master Accountant Network's Google Business Profile
- LinkedIn Founder: View expert Le Hoang Tuyen's LinkedIn profile.
Responsible for production and professional content review by: Mr. Le Hoang Tuyen – Founder & CEO of MAN – Master Accountant Network, CPA Vietnam with over 30 years of experience in accounting, auditing, taxation, and corporate financial consulting.
Frequently Asked Questions about the World's Leading Auditing Firms
What are the Big 4 auditing firms?
The Big 4 refers to the four largest auditing firms in the world: Deloitte, PwC, EY, and KPMG, which together hold the majority of the market share for auditing publicly listed corporations globally.
Is it mandatory for FDI businesses in Vietnam to hire the Big 4 firms?
Hiring a Big 4 firm is not mandatory. According to the Law on Independent Auditing No. 67/2011/QH12, FDI enterprises are only required to have their annual financial statements audited by a qualified auditing firm, which may belong to the Big 4 or a mid-tier firm.
Are audit fees at leading global auditing firms significantly more expensive than at domestic firms?
Yes. The fees charged by the Big 4 and international network firms are generally higher than those of domestic auditing firms due to the costs of operating a global network and the requirement for international quality standards, but the specific difference depends on the size and complexity of each business.
How can you tell if an auditing firm truly has an international network?
Businesses should check whether the auditing firm is an official member of an international network, compare the list of member offices in the parent company's country, and request the firm's profile and professional license issued by the Ministry of Finance.
Besides the Big 4, which auditing firms should medium-sized businesses choose?
Mid-tier firms like BDO, RSM, Grant Thornton, Baker Tilly, Crowe Global, or Nexia International are often better suited to medium-sized businesses due to their reasonable costs and personalized approach, while still maintaining the international network necessary for consolidated reporting.
