Choosing an accounting firm starts with understanding what your business actually needs: reliable reporting, tax support, an independent audit, or help expanding internationally.
This guide to the top 10 accounting firms in the world in 2026 compares major global networks, their services, and the businesses they may suit. It also explains the Big 4, the wider Big 10 discussion, and when a specialized firm makes sense for startups and SMBs.
Use the comparison below to build your shortlist before discussing your requirements with a local team.
Quick Answer / Top 10 at a Glance
The ten global accounting networks covered here are Deloitte, PwC, EY, KPMG, BDO, RSM, Grant Thornton, Baker Tilly, Crowe, and Forvis Mazars. Deloitte, PwC, EY, and KPMG form the Big 4; the remaining six offer additional international options.
This is an editorial comparison, not an official worldwide league table. Numbers identify the profiles below; they do not represent independently measured service quality or a verified 2026 revenue ranking.
| No. | Accounting network | Services to compare | Potential business fit |
|---|---|---|---|
| 1 | Deloitte | Audit, tax, consulting, strategy and transactions | Complex international groups and major transformation projects |
| 2 | PwC | Assurance, tax and advisory | Businesses with substantial reporting and international requirements |
| 3 | EY | Assurance, tax, consulting, strategy and transactions | Businesses preparing for transactions or organizational change |
| 4 | KPMG | Audit, tax and advisory | Organizations needing coordinated reporting and advisory support |
| 5 | BDO | Public accounting, tax and advisory | Private and listed companies expanding across markets |
| 6 | RSM | Assurance, tax and consulting | Growing businesses moving toward middle-market scale |
| 7 | Grant Thornton | Assurance, tax and advisory | Companies managing growth, transactions and overseas operations |
| 8 | Baker Tilly | Audit, tax and advisory | Businesses needing local advice with international coordination |
| 9 | Crowe | Audit, tax and advisory | Businesses seeking relevant local and industry expertise |
| 10 | Forvis Mazars | Audit, assurance, tax, advisory and consulting | Companies comparing international alternatives to the Big 4 |
Business-fit descriptions are editorial guidance based on published services. Availability, fees, independence requirements and team experience must be checked locally.
How We Selected the Top 10 Accounting Firms
We selected these ten international accounting networks because they combine cross-border coverage with accounting, assurance, tax or advisory capabilities relevant to business buyers. They also preserve the ten global names discussed in this article’s existing Big 10 section.
The comparison considers three practical factors:
- Service breadth: whether the network offers the support businesses commonly need as their reporting and operations become more complex.
- International coverage: whether local teams can support work across multiple markets.
- Business fit: how the published services relate to company size, growth plans and financial complexity.
Firm details were checked against official websites on September 18, 2026. “Best Suited For” describes a potential fit, not an exclusive specialization or a guarantee of results.
A global accounting firms ranking can change depending on whether it measures total revenue, audit revenue, headcount or geographic coverage. Reporting periods and network boundaries matter too: BDO, for example, distinguishes revenue including alliance firms from its other reported global total. BDO’s official overview explains that distinction.
For these reasons, this guide does not present mixed financial figures as a definitive ranking of the largest accounting firms in the world.
What Are the Big 10 Accounting Firms?
The term Big 10 accounting firms, also written as “Big Ten accounting firms,” is commonly used for a wider group of major accounting networks beyond the Big 4. It is an informal label, so the exact membership and order can differ between lists.
In this guide, the group includes Deloitte, PwC, EY, KPMG, BDO, RSM, Grant Thornton, Baker Tilly, Crowe, and Forvis Mazars.
These organizations support services ranging from audits to international tax work. However, a global accounting firm often operates through separate member firms rather than one company delivering every service worldwide. Grant Thornton and BDO explicitly describe their network structures in their official information. Grant Thornton, BDO.
For a client, the local firm, engagement team and agreed scope matter as much as the international brand.
Top 10 Accounting Firms in the World in 2026
1. Deloitte
Overview: Deloitte combines accounting-related services with a broad consulting business. Its published FY2025 aggregate global revenue was US$70.5 billion, illustrating the scale of its network.
- Best Known For: Large-scale audit, consulting and business transformation work.
- Key Services: Audit and assurance, tax, technology transformation, strategy, risk and transactions.
- Global Reach: More than 150 countries and territories.
- Best Suited For: International groups comparing providers for complex reporting, technology changes or acquisitions.
- Why It Stands Out: Its service range can support projects involving financial, operational and technology expertise, subject to engagement and independence requirements.
Sources: Deloitte FY2025 results and global facts and figures.
2. PwC
Overview: PwC is a global professional services network offering assurance, tax and advisory capabilities. Its 2025 annual review reports operations in 136 countries.
- Best Known For: Corporate assurance and broad business advisory services.
- Key Services: Assurance, tax, consulting and business strategy support.
- Global Reach: 636 cities across 136 countries, according to its 2025 review.
- Best Suited For: Businesses with substantial reporting obligations and operations across several markets.
- Why It Stands Out: Its international footprint and work with large companies make it a relevant option for organizations coordinating complex engagements.
Source: PwC Global Annual Review 2025.
3. EY
Overview: EY provides assurance, consulting, tax, strategy and transaction services. Its EY-Parthenon offering includes corporate strategy, due diligence and transaction support.
- Best Known For: Assurance alongside strategy and transaction capabilities.
- Key Services: Audit, financial accounting advisory, tax, consulting, valuations and M&A advisory.
- Global Reach: An international network with local practices serving clients across global markets.
- Best Suited For: Businesses comparing support for acquisitions, financial reporting changes or strategic growth.
- Why It Stands Out: Its published services span transaction planning and execution as well as the accounting questions that accompany business change.
Source: EY’s organization and service overview.
4. KPMG
Overview: KPMG is a global organization of independent firms providing audit, tax and advisory services to businesses and other organizations.
- Best Known For: Its three core service areas: audit, tax and advisory.
- Key Services: Audit engagements, tax support and business advisory services.
- Global Reach: 138 countries and territories, according to its official overview.
- Best Suited For: Organizations seeking support across financial reporting and broader business requirements.
- Why It Stands Out: Its international organization provides a substantial base of local teams for businesses evaluating multi-market engagements.
Source: About KPMG.
5. BDO
Overview: BDO supports private and listed companies through an international network of public accounting, tax and advisory firms. It is an option for businesses entering growth and expansion phases.
- Best Known For: Serving private businesses and listed companies through local member firms.
- Key Services: Public accounting, tax and business advisory.
- Global Reach: 169 countries and territories, as reported in its global network overview.
- Best Suited For: Companies whose accounting needs extend across multiple jurisdictions.
- Why It Stands Out: Its combination of local market knowledge and international coverage is relevant when a business begins operating beyond its home market.
Source: BDO’s global overview.
6. RSM
Overview: RSM sits among the international accounting firms that businesses consider when moving toward middle-market scale. Its stated focus includes growth-oriented entrepreneurial businesses and multinational organizations.
- Best Known For: Professional services focused on the middle market.
- Key Services: Audit and assurance, tax, consulting, risk advisory, restructuring and transaction support.
- Global Reach: A worldwide network combining local knowledge with cross-border expertise.
- Best Suited For: Growing companies whose reporting and operational requirements have become more complex.
- Why It Stands Out: Its middle-market focus provides a useful starting point for businesses comparing international providers at this stage.
Source: About RSM.
7. Grant Thornton
Overview: Grant Thornton is a global network providing assurance, tax and advisory services. Its official overview reports more than 150 markets worldwide.
- Best Known For: Assurance and advisory support for businesses managing growth and change.
- Key Services: Assurance, business tax, international tax, business consulting and transaction advisory.
- Global Reach: More than 150 markets.
- Best Suited For: Companies comparing support for international expansion, transactions or increasingly demanding reporting.
- Why It Stands Out: Its international network pairs local engagement teams with a broad range of business services.
Source: Grant Thornton’s network and services.
8. Baker Tilly
Overview: Baker Tilly is a global network of independent accounting and advisory firms. Its published network figures cover 147 territories and 754 offices.
- Best Known For: Accounting and advisory services delivered through independent local firms.
- Key Services: Audit, tax, advisory, corporate tax, transfer pricing and international tax.
- Global Reach: 147 territories, according to its published network figures.
- Best Suited For: Businesses needing local professional support alongside international coordination.
- Why It Stands Out: Its geographic coverage offers an alternative for companies comparing providers beyond the Big 4.
Source: Baker Tilly’s official network website.
9. Crowe
Overview: Crowe Global connects independent accounting and advisory firms. Its international offering emphasizes local business knowledge and specialist technical skills.
- Best Known For: Accounting and advisory support grounded in local market expertise.
- Key Services: Audit, tax and advisory services through participating firms.
- Global Reach: Member firms across the Americas, Europe, Asia Pacific, Africa and the Middle East.
- Best Suited For: Businesses evaluating a local team’s industry experience within an international network.
- Why It Stands Out: Its local expertise is relevant for clients whose requirements depend heavily on the markets where they operate.
Sources: About Crowe Global and its global locations and services.
10. Forvis Mazars
Overview: Forvis Mazars provides audit, assurance, tax, advisory and consulting services worldwide. Its group website describes an internationally integrated partnership within the wider global network.
- Best Known For: International audit, tax and advisory services.
- Key Services: Audit and assurance, tax, advisory and consulting.
- Global Reach: Its published overview describes coverage across more than 100 countries and territories.
- Best Suited For: Businesses comparing international accounting networks for domestic and cross-border requirements.
- Why It Stands Out: Its international structure makes it relevant to businesses seeking coordinated support beyond a single market.
Forvis Mazars is included in this guide’s Big 10 selection. Its number here is a profile position, not a claim that every worldwide ranking places it tenth.
Source: About Forvis Mazars.
Top Accounting Firms vs. Top Audit Firms
Searches for the top 10 audit firms in the world often return many of the same names as accounting-firm lists. However, the services and ranking criteria are different.
| Comparison | Accounting services | External financial statement audit |
|---|---|---|
| Main purpose | Prepare, maintain or interpret financial information | Independently examine financial statements and issue an audit opinion |
| Typical work | Bookkeeping, reporting and accounting support | Audit planning, evidence gathering and financial statement testing |
| Main selection question | Can the team meet the business’s accounting needs? | Is the firm eligible, independent and experienced for this audit? |
| What network size shows | Scale across multiple services | It does not, by itself, measure audit quality |
The phrase “top 10 audit companies” should therefore be treated as a starting point for research. A ranking based on total network revenue includes services beyond audit and cannot establish which audit team is right for you.
When comparing international audit firms, ask about relevant industry experience, local authorization, audit scope and applicable inspection findings. Accounting support and an independent audit are different engagements.
The Big 4 Accounting Firms
The Big 4 accounting firms are Deloitte, PwC, EY and KPMG. Each offers a broad range of services through its international organization.
- Deloitte: Audit and assurance alongside extensive consulting, tax and transaction services.
- PwC: Assurance, tax and advisory services across its global network.
- EY: Assurance, tax, consulting, strategy and transaction capabilities.
- KPMG: Audit, tax and advisory delivered through independent member firms.
Their size makes them relevant to complex international engagements, but the decision still depends on the work required and the proposed team. See the official sources linked in each profile for their service descriptions.
Why Businesses Choose Large Global Accounting Firms
Even businesses that choose a boutique firm early may eventually work with a larger international network. This can happen around audit requirements, acquisitions or expansion into new markets.
The main reasons to consider a global provider include:
- Audit: Coordinating an engagement involving multiple entities, locations and reporting teams.
- Tax: Accessing specialists familiar with the jurisdictions in which the business operates.
- Advisory: Improving financial processes, controls, systems or management reporting.
- Mergers and acquisitions: Assessing financial information and preparing for a transaction or integration.
- International expansion: Connecting local requirements with the needs of the wider group.
The services described in the profiles show why global coverage can be useful. Before appointing a provider, ask who will coordinate the work and what each local team will deliver.
What About Accounting Firms for Startups and SMBs?
Founders juggling product launches and investor calls rarely have time to vet a dozen firms one by one. The decision shapes everything from cash runway to fundraising readiness.
However, most early-stage startups do not need enterprise-level infrastructure on day one. A specialized firm may be a better fit when the immediate priorities are accurate books, timely reporting and accessible advice.
A startup may need additional accounting support when monthly reporting falls behind, investors request financial information, or the business begins operating across multiple entities. The right provider should understand the company’s stage and the specific work involved.
Some businesses can keep their existing accounting team while appointing a separate auditor or transaction specialist as requirements grow.
For US startups and SMBs, 5K Advisory offers accounting and business advisory support. Discuss your reporting needs, current systems and growth plans to establish an appropriate scope of work.
How to Choose the Right Accounting Firm
In the end, the best accounting partner depends on your stage, industry and specific financial complexity.
Compare the following before deciding:
- Business size: Ask whether the proposed team regularly supports companies at your stage and scale.
- Required service: Be specific about bookkeeping, reporting, tax, audit or advisory deliverables.
- Industry experience: Request examples of relevant work and discuss the reporting challenges common in your sector.
- Geography: Confirm that the provider can support the locations where you operate or intend to expand.
- Complexity: Explain your entities, systems, transactions and reporting deadlines before requesting a proposal.
Also compare fees, exclusions, communication arrangements and responsibility for reviewing the work. Ask who will handle your account after the initial sales conversation.
Choosing among the top 10 accounting firms is about matching a firm’s strengths to where your business actually stands today. Understanding this early, rather than scrambling later, gives founders and finance teams a practical advantage.
Frequently Asked Questions
What are the top ten accounting firms in the world?
This guide covers Deloitte, PwC, EY, KPMG, BDO, RSM, Grant Thornton, Baker Tilly, Crowe and Forvis Mazars. It is a comparison of ten major global networks rather than an official ranking of service quality.
What is the biggest accounting firm?
Deloitte is widely identified as the largest global accounting and professional services network by total revenue. It reported US$70.5 billion for FY2025; that figure includes services beyond audit and accounting. Deloitte FY2025 revenue announcement.
Are the Big 10 audit firms the same as the Big 10 accounting firms?
The names often overlap because major networks provide both accounting-related services and audit. However, “Big 10” is an informal label, and audit-specific rankings can use different measures from total network revenue.
Is Forvis Mazars a Big 10 accounting firm?
Forvis Mazars is included in this article’s Big 10 comparison. For a precise worldwide position, check the ranking’s date, methodology and whether it measures the global network or a particular member firm. Forvis Mazars organization overview.
Is there one best audit firm for every business?
No. The appropriate choice depends on the audit required, the firm’s eligibility and independence, the engagement team’s experience, and the jurisdictions involved. A recognizable name alone does not settle those questions.
Should a small business choose an international accounting firm?
It depends on the work involved. A business operating locally may need a specialist local provider, while overseas entities or complex transactions may justify international support. Compare the proposed scope and team before deciding.
Do global accounting companies operate as one business worldwide?
Many operate through legally separate member firms under a shared brand. Confirm which entity will sign the engagement and perform the work; Grant Thornton, for example, explicitly distinguishes its international organization from its member firms. Grant Thornton’s network information.
Conclusion
The top 10 accounting firms in the world offer a useful starting point for comparing international expertise, service breadth and business fit. Your shortlist should reflect the work you need and the team that will deliver it.
For startups and SMBs, the right support may begin with a more focused engagement. Contact 5K Advisory to discuss your accounting needs and the next stage of your business.