The Big 4 accounting firms, also called the Big Four, are Deloitte, PwC, EY, and KPMG. They audit most of the world’s largest listed companies and offer tax, consulting, and advisory services.
Together, the four firms earn about $230 billion a year and employ more than 1.5 million people. Knowing what each does helps businesses, finance professionals, and job seekers choose a firm.
This guide profiles each firm in detail and compares them across services, audit quality, and culture. It also covers alternatives, controversies, careers, and how to choose the right firm.
You will learn the following:
- The Big 4 accounting firms are Deloitte, PwC, EY, and KPMG. Deloitte leads with $74.5 billion in FY2026 revenue.
- Each firm is a network of legally separate member firms, and none is publicly traded.
- No single Big 4 accounting firm is best for every client, because strengths differ by service line and industry.
- The Big Four US firms audit about 80% of US-listed market capitalization, according to the PCAOB.
- Mid-tier firms and CPA-led boutiques often fit growing businesses better than the Big 4.
- Audit quality, independence rules, and market concentration remain active regulatory concerns.
The Big 4 Accounting Firms
This table summarizes the four firms. Revenue and headcount use each firm’s latest reported fiscal year.
| Firm | Full Name | Network Base | Latest Revenue | Employees | Primary Strength |
|---|---|---|---|---|---|
| Deloitte | Deloitte Touche Tohmatsu Limited | London, UK | $74.5B (FY2026) | Nearly 500,000 | Consulting, technology, AI, audit, and advisory |
| PwC | PricewaterhouseCoopers International Limited | London, UK | $60.2B (FY2026) | 369,945 | Audit and assurance, tax, deals, and consulting |
| EY | Ernst & Young Global Limited | London, UK | $57.0B (FY2026) | 415,182 | Assurance, strategy, transactions, tax, and consulting |
| KPMG | KPMG International Limited | London, UK | $39.8B (FY2025) | 276,030 | Audit, tax, advisory, and risk |
Three firms reported FY2026 results in September and October 2026. However, KPMG usually reports in December, so its figures are a year behind.
Sources: Deloitte FY2026 results, PwC FY2026 results, EY FY2026 results, and KPMG FY2025 results.
Big 4 Accounting Firms: Key Industry Data
These figures come from the firms and the regulators that oversee them. The table lists the source for each.
| Metric | Data Point | Source |
|---|---|---|
| Combined annual revenue | About $231 billion (Deloitte, PwC, and EY FY2026; KPMG FY2025) | Firm results releases |
| Total employees | More than 1.5 million | Firm results releases |
| US-listed market capitalization audited by the Big Four US firms | About 80% at the end of 2025 | PCAOB |
| FTSE 350 audits carried out by firms outside the Big Four | 48, up from 41 in 2023 | FRC Key Facts and Trends 2025 |
| Big Four US firms’ PCAOB Part I.A deficiency rate | 8% in 2025, down from 20% in 2024 and 26% in 2023 | PCAOB |
| Countries and territories | More than 150 (Deloitte) and 142 (KPMG) | Firm websites |
| Year Arthur Andersen left public company auditing | 2002 | Court records |
A Part I.A deficiency means the firm had not obtained enough evidence to support its audit opinion. The PCAOB reports these rates after each inspection cycle.
Sources: PCAOB 2025 inspections update and the FRC 2025 report.
What Are the Big 4 Accounting Firms?
The Big 4 accounting firms are Deloitte, PwC (PricewaterhouseCoopers), EY (Ernst & Young), and KPMG. They are the four largest professional services firms in the world by revenue.
Accounting Big 4 refers to the four firms that dominate global professional services. Each provides audit and assurance, tax advisory, consulting, financial advisory, and risk services to corporations, governments, nonprofits, and financial institutions worldwide.
The Big 4 companies audit the large majority of the biggest listed companies. That dominance reflects regulatory requirements, liability considerations, and the global infrastructure needed to audit multinational corporations.
Are the Big 4 Public or Private Companies?
The Big 4 are private organizations, and none is publicly traded.
Each firm is a network of independently owned member firms. Partners own many of those firms, so there is no stock to buy.
Each network’s coordinating entity is a private UK company limited by guarantee.
In contrast, some mid-tier firms have taken private equity investment. CBIZ is publicly traded until its sale to Grant Thornton Advisors closes.
How Are the Big 4 Structured?
None of the four is a single company. Instead, each is a network of legally separate member firms that share a brand, methods, and quality standards.
Each member firm is owned locally and serves clients in its own country. Therefore, Deloitte US and Deloitte Australia are separate legal entities.
However, consolidation is changing the model. On June 1, 2026, Deloitte combined 16 European, Middle Eastern, and African firms into one firm, Deloitte EMEA.
A coordinating entity sets standards for each network but does not serve clients. Specifically, for Deloitte, PwC, and EY, that entity is a UK company.
However, KPMG was the exception until 2020, when a Swiss cooperative coordinated its network. Since then, KPMG International Limited, an English company, has played that role.
Why Are They Called the Big 4?
The term Big 4 reflects consolidation in the global accounting industry from the 1980s to the early 2000s.
Eight dominant firms once led the industry, and mergers cut that number step by step.
The original Big 8 were Arthur Andersen, Arthur Young, Coopers & Lybrand, and Deloitte Haskins & Sells. Four more were Ernst & Whinney, Peat Marwick Mitchell, Price Waterhouse, and Touche Ross.
- 1987: Peat Marwick Mitchell and Klynveld Main Goerdeler merged to form KPMG.
- 1989: Ernst & Whinney and Arthur Young formed Ernst & Young. Deloitte Haskins & Sells and Touche Ross formed Deloitte & Touche. The Big 8 became the Big 6.
- 1998: Price Waterhouse and Coopers & Lybrand merged to form PwC, which created the Big 5.
- 2002: Arthur Andersen collapsed after the Enron scandal, which left four firms.
As a result, the Big Four label has stood since 2002.
What Happened to Arthur Andersen?
Arthur Andersen was a Big Five firm that collapsed in 2002 after the Enron accounting scandal.
Andersen was Enron’s auditor. A jury convicted the firm of obstruction of justice on June 15, 2002, for destroying Enron-related documents.
As a result, clients left, and the firm gave up its right to audit public companies. In 2005, the US Supreme Court unanimously overturned the conviction, but the firm never recovered.
Its consulting arm had already split off. Andersen Consulting became Accenture on January 1, 2001.
Congress then passed the Sarbanes-Oxley Act in 2002, which tightened auditor independence rules.
What Services Do the Big 4 Accounting Firms Provide?
All four firms offer the same broad menu of services. However, the mix and emphasis differ by firm.
- Audit and assurance: independent checks that financial statements are fairly presented. Auditors also test internal controls and provide other assurance reports.
- Tax: corporate tax planning, international tax, transfer pricing, indirect tax, and compliance. Many teams also advise executives and private clients on personal tax and global mobility.
- Consulting: technology, operations, human capital, and strategy projects, including AI and enterprise transformation.
- Financial advisory: mergers and acquisitions, restructuring, valuations, and forensic accounting.
- Risk advisory: cybersecurity, regulatory compliance, internal controls, and enterprise risk.
- Legal services: offered in some countries through affiliated legal practices.
Consulting and advisory now make up a large share of revenue at each firm. As a result, the Big 4 are much more than audit firms.
Audit is the most regulated service. In the US, the PCAOB inspects the largest firms every year and publishes the results.
What Is Deloitte? Overview, Services, and What It Is Known For
Deloitte is the world’s largest professional services firm by revenue, with $74.5 billion in FY2026.
Founded in London in 1845 by William Welch Deloitte, Deloitte operates in over 150 countries and territories with nearly 500,000 people.
Joe Ucuzoglu serves as Deloitte Global CEO. Its coordinating entity, Deloitte Touche Tohmatsu Limited, is a UK company that does not serve clients.
What Is Deloitte Known For?
Deloitte is best known for consulting and technology services. In addition, it competes with major strategy firms for large transformation projects.
Its Omnia audit platform now includes generative AI. Deloitte’s agentic AI capabilities were named the 2026 Digital Innovation of the Year by the International Accounting Forum and Awards.
Deloitte University, a leadership campus in Westlake, Texas, also reflects the firm’s investment in talent development.
Deloitte: Core Services and Strengths
The firm reports four business units. The table shows what each covers and how fast each grew in FY2026.
| Business Unit | What Deloitte Does | FY2026 Growth (Local Currency) |
|---|---|---|
| Audit and Assurance | Financial statement audits, PCAOB audits, internal audit, and other assurance | 5% |
| Tax and Legal | Corporate tax, international tax, transfer pricing, indirect tax, and legal services | 5.8% |
| Strategy, Risk and Transactions | Strategy, M&A advisory, restructuring, forensic accounting, valuations, and risk advisory | 4.4% |
| Technology and Transformation | Technology consulting, engineering, AI, and enterprise transformation | 2.5% |
Tax and Legal grew fastest. In contrast, Technology and Transformation grew the slowest.
What Is PwC (PricewaterhouseCoopers)? Overview, Services, and What It Is Known For
PwC is the second-largest Big 4 accounting firm by revenue, with $60.2 billion in FY2026.
PwC formed in 1998 from the merger of Price Waterhouse (founded 1849) and Coopers & Lybrand (founded 1854). It has 369,945 people.
PricewaterhouseCoopers International Limited, an English company, coordinates the network. Mohamed Kande serves as Global Chairman.
In its FY2025 review, PwC reported 136 countries and 137 territories. In FY2026, it invested $3 billion across the network, with a focus on AI and technology.
What Is PwC Known For?
PwC is best known for audit and assurance, tax, and deals advisory. Vault ranked it first in its 2027 Accounting 25 and in its prestige ranking.
Its audit platform, Aura, is used on every PwC audit worldwide, according to the firm.
PwC is also known for research. Its annual Global CEO Survey and State of Climate Tech report are widely cited.
Strategy&, its strategy consulting business, grew from the 2014 acquisition of Booz & Company.
PwC: Core Services and Strengths
PwC reports three lines of service. Specifically, the table shows what each covers and how fast each grew.
| Line of Service | What PwC Does | FY2026 Growth (Like-for-Like, Constant Currency) |
|---|---|---|
| Assurance | Financial statement audits, PCAOB compliance, SOX attestation, and assurance | 2.6% |
| Advisory | Deals, strategy, transformation, technology, consulting, and risk | 3.0% |
| Tax and Legal Services | M&A tax, international tax, indirect tax, private client, and legal services | 6.3% |
Tax and Legal Services grew fastest. In contrast, Assurance grew the slowest.
What Is EY (Ernst & Young)? Overview, Services, and What It Is Known For
EY is the third-largest Big 4 accounting firm by revenue, with $57.0 billion in FY2026.
EY formed in 1989 through the merger of Ernst & Whinney and Arthur Young. It adopted the short EY brand in 2013.
EY has 415,182 people and operates in about 150 countries. Janet Truncale serves as Global Chair and CEO.
Ernst & Young Global Limited, a UK company based in London, coordinates the network.
What Is EY Known For?
EY is widely associated with transactions advisory and private equity work. Its strategy arm, EY-Parthenon, is one of the best-known strategy practices.
Also, its Entrepreneur Of The Year program gives it a visible profile among growth companies.
EY said its AI services sales grew 49% in FY2026. It also embedded agentic AI into EY Canvas, its global assurance platform.
In 2022, EY announced a plan to split its audit and consulting businesses, known as Project Everest. The firm abandoned the plan in 2023 after US partners opposed it.
The episode highlighted the tension between audit independence and the growth of consulting revenue.
EY: Core Services and Strengths
EY reports four service lines. The table shows what each covers, its FY2026 revenue, and its growth.
| Service Line | What EY Does | FY2026 Revenue | Growth (Local Currency) |
|---|---|---|---|
| Assurance | Financial statement audits, IFRS advisory, and internal audit | $18.9 billion | 3.0% |
| Consulting | Technology transformation, business operations, and risk | $17.4 billion | 4.4% |
| Tax | Business tax, international tax, indirect tax, and people advisory | $13.8 billion | 6.0% |
| EY-Parthenon | Strategy and transactions, including M&A advisory, restructuring, and valuations | $6.8 billion | 7.4% |
EY-Parthenon grew fastest. However, Assurance remains the largest line by revenue.
What Is KPMG? Overview, Services, and What It Is Known For
KPMG is the fourth-largest Big 4 accounting firm by revenue, with $39.8 billion in FY2025.
KPMG stands for Klynveld Peat Marwick Goerdeler, the names of the founders. It formed in 1987 when Peat Marwick International merged with Klynveld Main Goerdeler.
KPMG has 276,030 people in 142 countries and territories. Its FY2026 results are due in December.
KPMG International Limited, registered in London, coordinates the network. Bill Thomas serves as Global Chairman and CEO.
What Is KPMG Known For?
KPMG is recognized for audit, tax, and risk advisory. It has a long-standing focus on financial services, government, and public sector clients.
KPMG Clara is its global audit platform, and KPMG says it was the first Big Four platform on Microsoft Azure. It also launched Workbench, its AI platform.
The firm plans to invest about $4.2 billion in technology and AI by 2026.
However, KPMG has faced audit quality scrutiny. The FRC fined it a record £21 million over its Carillion audits in 2023.
In 2025, its US firm had the highest PCAOB deficiency rate of the Big Four, at 13%. The firm has invested in audit quality programs in response.
Despite these challenges, KPMG remains a dominant force in professional services and a sought-after employer for accounting graduates.
KPMG: Core Services and Strengths
KPMG reports three service lines. Specifically, the table shows what each covers and how fast each grew.
| Service Line | What KPMG Does | FY2025 Growth (Local Currency) |
|---|---|---|
| Audit | Financial statement audits, PCAOB audits, and audit quality programs | 6.0% |
| Tax and Legal | Corporate tax, international tax, indirect tax, global mobility, and legal services | 7.5% |
| Advisory | Risk consulting, management consulting, technology, and deals | 2.9% |
Tax and Legal grew fastest. However, Advisory grew the slowest.
Big 4 Accounting Firms Compared: Deloitte vs PwC vs EY vs KPMG
All four of the top 4 accounting firms provide the same core services: audit, tax, advisory, and consulting. The differences lie in scale, specialization, industry focus, and culture.
Who are the Big 4 accounting firms best suited for? The answer depends on what a client needs and which firm has the deepest expertise in that area.
| Comparison Factor | Deloitte | PwC | EY | KPMG |
|---|---|---|---|---|
| Latest revenue | $74.5B (FY2026) | $60.2B (FY2026) | $57.0B (FY2026) | $39.8B (FY2025) |
| Employees | Nearly 500,000 | 369,945 | 415,182 | 276,030 |
| Fastest-growing line | Tax and Legal (5.8%) | Tax and Legal (6.3%) | EY-Parthenon (7.4%) | Tax and Legal (7.5%) |
| Audit platform | Omnia | Aura | Canvas and Helix | Clara |
| 2025 PCAOB deficiency rate (US) | 5% | 9% | 5% | 13% |
| Vault prestige rank (2027) | 2 | 1 | 3 | 4 |
| Vault Accounting 25 (2027) | Outside the top 3 | 1 | 2 | 3 |
| Commonly associated with | Consulting and technology | Audit, tax, and deals | Transactions and strategy | Audit, tax, and risk |
Global leader
Joe Ucuzoglu
Mohamed Kande
Janet Truncale
Bill Thomas
PCAOB rates are estimates for the US firms and come from risk-based samples. Therefore, treat them as one signal, not a quality score.
Which Big 4 Firm Is Best for Different Needs?
- For large-scale technology transformation: Deloitte is commonly associated with the largest consulting programs and competes with strategy firms.
- For audit and assurance: PwC leads Vault’s prestige ranking, while Deloitte and EY posted the lowest 2025 PCAOB deficiency rates among the four.
- For M&A transactions and private equity: EY is commonly associated with transactions advisory through EY-Parthenon.
For government, public sector, and risk advisory: KPMG has a long-standing focus on these sectors.
- For financial services: PwC and KPMG have long-standing financial services audit practices.
However, these reputations are generalizations. Therefore, compare the specific team, industry experience, and fees before you choose.
Big 4 vs Boutique and Niche Firms for Cybersecurity, Tax, and Deals
All four firms run large cybersecurity, tax, and deals practices. Niche firms, in contrast, focus on one area and can move faster on specialized projects.
- Breadth: the Big 4 combine audit, tax, technology, and risk teams, which helps on projects that cross several functions.
- Depth: niche firms can offer deeper expertise in one area, such as indirect tax or a specific cybersecurity discipline.
- Technology: the Big 4 invest heavily in proprietary platforms. Boutiques often rely on partner tools and specialist software.
- Client support: smaller firms often give clients more direct partner access, while the Big 4 staff larger teams.
- Independence: an audit client cannot buy certain non-audit services from its auditor, so clients often split the work.
Therefore, match the firm to the problem. A single-area project may suit a specialist, while a multi-country program may need a Big 4 network.
Big 4 vs Mid-Tier Audits: Methodology, Independence, and Client Service
Many buyers ask how audit methodology, independence standards, and client service differ between the Big 4 and mid-tier firms. The rules are the same, but the models differ.
Audit Methodology and Technology
PCAOB standards govern every US public company audit, whoever the auditor is. Each Big 4 network adds its own global methodology and platform.
- Deloitte: Omnia, which now includes generative AI.
- PwC: Aura, used on every PwC audit worldwide.
- EY: Canvas, with Helix analytics and embedded AI agents.
- KPMG: Clara, its global smart audit platform.
Mid-tier networks such as BDO, Grant Thornton, and RSM run their own methodologies and tools. However, they usually invest at a smaller scale.
Independence Standards
The same independence rules apply to every SEC registrant’s auditor. Under the Sarbanes-Oxley Act, three core requirements stand out.
- Prohibited services: an auditor cannot give an audit client certain non-audit services, including bookkeeping, valuations, actuarial work, and internal audit work.
- Pre-approval: the audit committee must approve permitted non-audit services in advance, with a small exception.
- Partner rotation: the lead and reviewing audit partners must rotate off after five consecutive years.
These rules apply equally to the Big 4 and to mid-tier firms. Tax services remain allowed for audit clients with committee pre-approval.
Private equity investment adds another question. Many mid-tier firms have taken PE capital, so ask how the firm structures audit independence.
Client Service Models and Audit Quality
The Big 4 offer global reach and deep benches. Mid-tier firms usually offer more direct partner access and lower fees.
PCAOB inspection data adds context. In 2025, the Big Four US firms’ combined deficiency rate was 8%. BDO USA and Grant Thornton posted 34% and 33%.
However, the PCAOB samples by risk and the mid-tier samples were small, so treat these as signals.
Therefore, compare methodology, independence safeguards, and the team assigned to your audit.
How Are the Big 4 Using AI?
All four firms are investing heavily in AI. The investments touch audit, tax, and consulting work.
- PwC: invested $3 billion across its network in FY2026, with a focus on AI and technology.
- KPMG: plans to invest about $4.2 billion in technology and AI by 2026 and launched its Workbench AI platform.
- EY: reported 49% growth in AI services sales in FY2026 and embedded AI agents in EY Canvas.
- Deloitte: added generative and agentic AI to Omnia and won a 2026 digital innovation award for it.
As a result, routine audit and tax tasks are shifting toward automation. However, professional judgment still sits with the engagement team.
Who Are the Largest Accounting Firms After the Big 4?
Mid-tier firms rank below the Big 4 by revenue but serve many mid-market and private companies. Mergers and private equity are reshaping this group quickly.
| Firm | Approx. US Revenue | Notes |
|---|---|---|
| RSM US | About $4.0 billion | Fifth-largest US firm, focused on the middle market |
| Baker Tilly | About $3.5 billion | Merged with Moss Adams in June 2025 and became the sixth-largest US firm |
| BDO USA | About $2.9 billion | Employee-owned through an ESOP and part of the global BDO network |
| CBIZ | About $2.8 billion | Publicly traded; Grant Thornton Advisors agreed to acquire it in July 2026 |
| Grant Thornton | About $2.4 billion | Took private equity investment in 2024; the CBIZ deal would create a $7.5 billion global platform |
| Forvis Mazars | About $2.3 billion | Formed from the BKD and DHG merger, then combined with Mazars in 2024 |
| Crowe | About $1.3 billion | Chicago-based national firm |
Sources: Accounting Today Top 100 and the Grant Thornton Advisors announcement.
Revenue figures are rounded and vary slightly by ranking source. The CBIZ deal is expected to close in the fourth quarter of 2026.
Alternatives to the Big 4 for Audit and Tax
Mid-tier firms such as RSM, BDO, Grant Thornton, Crowe, Baker Tilly, and Forvis Mazars audit many private and mid-market companies. Regional CPA firms and CPA-led boutiques serve smaller businesses.
Large public companies still usually choose a Big 4 auditor. In contrast, most private companies can choose any qualified firm.
Baker Tilly versus the Big 4, or BDO versus the Big 4, is the same trade-off. You weigh global reach against partner access and fees.
Many of the fastest-growing firms now have private equity backing. As a result, ownership and independence safeguards deserve a direct question.
Big 4 vs Mid-Tier vs CPA-Led Boutique
| Factor | Big 4 | Mid-Tier Firms | CPA-Led Boutiques |
|---|---|---|---|
| Typical clients | Global and listed companies | Mid-market and private companies | Small and growing businesses |
| Public company audits | Most large listed companies | Some smaller listed companies | Rarely |
| Fees | Premium rates | Lower than the Big 4 | Flexible, often fixed or monthly |
| Partner access | Limited for small clients | Moderate | High |
| Reach | Strongest global network | Network affiliations | Local or specialized |
When Should a Business Use the Big 4 vs a Regional or Specialized Accounting Firm?
The Big 4 accounting firms are the right choice for large, complex, and multinational organizations that need global infrastructure and expertise.
For smaller and mid-market businesses, the Big 4 are often not the most practical or cost-effective choice.
Big 4 firms charge premium rates that reflect their brand, global reach, and talent. A mid-market manufacturer that needs an annual audit and tax preparation rarely needs a Big 4 engagement.
A regional CPA firm or specialized accounting and bookkeeping services often fit mid-market needs better.
Our external audit support also helps businesses prepare for audits by any firm.
| Business Situation | Big 4 Recommended? | Better Alternative |
|---|---|---|
| Publicly traded company needing an SEC-registered audit | Usually | Big 4 for large caps; a PCAOB-registered mid-tier firm for smaller issuers |
| Private equity portfolio company before an IPO | Often | Big 4 or a top mid-tier firm |
| Large multinational with 20+ country operations | Yes | Big 4, because global infrastructure is required |
| Mid-market company ($10M to $500M revenue) | Often not | RSM, BDO, Grant Thornton, Baker Tilly, or a regional CPA firm |
| Small business ($1M to $10M revenue) | No | Regional CPA firm or CPA-led accounting provider |
| Startup or early-stage company | No | Specialized startup accounting firm or fractional CPA support |
| Large, complex M&A transaction | Yes | Big 4 transaction advisory |
| Mid-market M&A transaction | Sometimes | Mid-tier firm or specialized boutique M&A advisor |
These thresholds are rules of thumb, not rules. Your lenders, investors, and complexity matter more than revenue alone.
What Is It Like to Work at a Big 4 Accounting Firm?
The Big 4 accounting firms are among the most sought-after employers for accounting, finance, and business graduates worldwide.
A Big 4 career offers structured training, global exposure, CPA exam support, and a recognized credential. In addition, many finance leaders begin in public accounting.
The work is demanding. Hours run long during audit busy season, from about January through April, and around major transaction deadlines.
In return, the learning curve is steep, and the network built during a two-to-four-year tenure can shape a career. Many professionals then move into controller, CFO, private equity, or consulting roles.
Big 4 Career Structure
| Level | Typical Title | Years of Experience | Primary Responsibilities |
|---|---|---|---|
| Entry | Associate or Analyst | 0 to 2 years | Fieldwork, data gathering, testing, and client deliverable preparation |
| Senior | Senior Associate or Senior Analyst | 2 to 4 years | Leading workstreams, reviewing junior work, and client interaction |
| Manager | Manager | 4 to 7 years | Project leadership, client relationships, and team management |
| Senior Manager | Senior Manager or Director | 7 to 10 years | Practice development, complex client issues, and business development |
| Partner or Principal | Partner | 10+ years | P&L ownership, client origination, and firm governance and strategy |
Big 4 Salary Ranges (US Market)
Pay varies by function, city, and firm, and the firms do not publish scales. The ranges below combine public visa filings and salary reports.
| Level | Typical Base Salary Range | Notes |
|---|---|---|
| Associate | $55,000 to $90,000 | Audit and tax start lower, and consulting starts higher |
| Senior Associate | $75,000 to $115,000 | Pay runs higher in New York and other large markets |
| Manager | $110,000 to $180,000 | Public H-1B filings show medians of about $130,000 to $180,000 |
| Senior Manager | $140,000 to $250,000 | Consulting and advisory pay sits at the top of the range |
| Partner | $300,000 to $1 million or more | Equity partners earn a share of firm profits |
Bonuses and benefits add to base pay. Check current offers, because ranges shift by year and location.
Which Big 4 Firm Is Best to Work For?
Vault surveys accounting professionals each year. In its 2027 Accounting 25, PwC placed first overall, followed by EY and KPMG.
Deloitte ranked second for prestige, behind PwC.
However, the best firm depends on the practice, the office, and the team. Therefore, talk to current employees before you decide.
Big 4 vs Mid-Tier Firms for Your Career
- Big 4 firms: offer a recognizable name, large global clients, and often higher starting pay.
- Mid-tier firms: often offer broader day-to-day work, closer partner contact, and a more flexible schedule.
- Both: support the CPA exam and provide strong training for early-career accountants.
However, experiences vary by office and team, so talk to current employees before you decide.
How Do You Get a Job at a Big 4 Firm?
Landing a role takes preparation. In addition, early applications matter.
- Apply early: internships and campus recruiting are common entry points.
- Build core skills: organization, communication, and problem-solving matter in every interview.
- Plan the CPA exam: the firms typically support CPA licensure for new hires.
- Practice interviewing: campus events and mock interviews help you understand what each firm values.
Common Misconceptions About the Big 4 Accounting Firms
Several widely held beliefs about the Big Four accounting firms are incomplete or inaccurate.
- The Big 4 are a single organization: each firm is a network of legally independent member firms. Deloitte US and Deloitte Australia are separate entities that share a brand and standards.
- Big 4 firms are publicly traded: all four are private networks, so you cannot buy their stock.
- Audit is all the Big 4 do: consulting, advisory, risk, and tax make up most of EY’s revenue, for example. Assurance is about a third.
- You must stay at a Big 4 firm: many professionals stay two to four years before moving into industry roles. The Big 4 are often a launchpad, not a destination.
- A clean audit opinion guarantees accuracy: it means the auditor found no material misstatement. It does not guarantee that fraud is impossible.
- Mid-market businesses need the Big 4: most private companies below $500 million in revenue do well with a qualified regional firm.
What Criticisms and Controversies Surround the Big 4?
Regulators and critics raise concerns about audit quality, market concentration, and conflicts between audit and consulting work.
- Audit quality: PCAOB inspections found significant deficiencies in 8% of reviewed Big Four audits in 2025, down from 26% in 2023. However, some commentators question the sharp drop.
- Market concentration: competition is limited because large public companies usually insist on a Big 4 audit. In contrast, UK regulators have pushed the firms to separate audit and consulting operations.
- Audit and consulting conflicts: consulting fees can threaten auditor independence. EY’s 2022 plan to split the two, known as Project Everest, collapsed in 2023.
- Major scandals: Enron and Arthur Andersen ended the Big 5 in 2002. Later cases include Carillion in 2018, audited by KPMG, and Wirecard in 2020, audited by EY.
- Regulatory penalties: the FRC fined KPMG a record £21 million over its Carillion audits in 2023. Also, in 2022, EY agreed to pay $100 million to settle US charges over exam cheating.
- Conduct issues: a 2023 tax-leaks scandal at PwC Australia forced leadership changes and the sale of its government advisory business.
These are examples, not a full list. Moreover, each firm has faced regulator actions in other countries.
Frequently Asked Questions
What are the Big 4 accounting firms?
The Big 4 accounting firms are Deloitte, PwC (PricewaterhouseCoopers), EY (Ernst & Young), and KPMG.
Together, they are the world’s largest professional services organizations. They provide audit, tax, advisory, and consulting services in more than 140 countries and territories.
Who are the Big 4 accounting firms?
The Big 4 accounting firms are Deloitte (the largest by revenue), PwC, EY, and KPMG.
All four are coordinated by UK companies based in London, but they operate as global networks of member firms. Together, they employ more than 1.5 million people.
What do the Big 4 accounting firms do?
They provide audit and assurance, tax advisory, consulting, and financial advisory services.
Audit and assurance is their most regulated work. Tax advisory covers corporate tax strategy, international structuring, transfer pricing, and compliance.
In addition, consulting covers technology, operations, and strategy. Financial advisory covers M&A, restructuring, forensic accounting, and valuations.
Where are the Big 4 accounting firms located?
The Big 4 coordinating entities are UK companies based in London. Each firm operates through member firms in more than 140 countries and territories.
The US is the largest single market for each firm, and the US firms are based in New York. Each country’s member firm is a separate legal entity.
What is big 4 accounting firms?
Big 4 accounting firms is the collective term for Deloitte, PwC, EY, and KPMG, the four largest accounting networks.
They dominate global audit, tax, and advisory markets and earn about $230 billion a year combined. The term replaced Big 5 after Arthur Andersen collapsed in 2002.
What is the Big 4 in accounting?
The Big 4 in accounting refers to Deloitte, PwC, EY, and KPMG, the four firms that dominate audit, tax, and advisory.
They are known for audit work on large public companies. For finance professionals, Big 4 experience is one of the most recognized credentials.
Are the Big 4 public or private companies?
The Big 4 are private networks, and none is publicly traded.
Each is a network of locally owned member firms, coordinated by a private UK company limited by guarantee.
Why are they called the Big 4?
They are the four firms left after decades of mergers and the 2002 collapse of Arthur Andersen.
Also, before that, people called the group the Big 8, the Big 6, and the Big 5.
What happened to Arthur Andersen?
Arthur Andersen collapsed in 2002 after its conviction for obstruction of justice in the Enron scandal.
The Supreme Court overturned the conviction in 2005, but the firm never recovered.
What is Deloitte and what is it known for?
Deloitte is the largest professional services firm by revenue, at $74.5 billion in FY2026, and is known for consulting and technology.
Its full name is Deloitte Touche Tohmatsu Limited. Beyond consulting, it has a global audit practice and large M&A, restructuring, and risk advisory teams.
What is PwC (PricewaterhouseCoopers) and what is it known for?
PwC is the second-largest Big 4 firm, at $60.2 billion in FY2026. It is known for audit and assurance, tax, and deals advisory.
PricewaterhouseCoopers formed in 1998 from Price Waterhouse and Coopers & Lybrand. Its annual Global CEO Survey is widely cited.
What is EY (Ernst & Young) and what is it known for?
EY is the third-largest Big 4 firm, at $57.0 billion in FY2026. It is known for transactions advisory, private equity work, and strategy through EY-Parthenon.
Ernst & Young formed in 1989 and rebranded as EY in 2013. Its Entrepreneur Of The Year program is a well-known business award.
What is KPMG and what does it stand for?
KPMG is the fourth-largest Big 4 firm, at $39.8 billion in FY2025. It stands for Klynveld Peat Marwick Goerdeler.
The name reflects the founding firms that merged in 1987. KPMG is known for audit, tax, and risk advisory, and its coordinating entity is based in London.
What is each Big 4 firm known for?
Deloitte is known for consulting and technology, and PwC for audit and tax. EY is known for transactions and strategy, and KPMG for audit, tax, and risk advisory.
However, these reputations are generalizations, so compare teams and fees.
What is the difference between the Big 4 accounting firms?
All four provide audit, tax, advisory, and consulting. The main differences are size, industry focus, and service-line strength.
Deloitte is the largest and is known for consulting. PwC is known for audit and tax, EY for transactions and strategy, and KPMG for audit and risk.
For most engagements, the choice comes down to industry expertise, existing relationships, and price.
Which of the Big 4 accounting firms is best?
No single firm is best for every client.
PwC leads Vault’s 2027 rankings, while Deloitte and EY had the lowest 2025 PCAOB deficiency rates. Compare teams, industry experience, and fees for your need.
Which Big 4 firm is best to work for?
Vault’s 2027 rankings place PwC first, followed by EY and KPMG.
Deloitte ranked second for prestige. However, culture varies by office and team.
How do the Big 4 compare to mid-market accounting firms?
The Big 4 serve large, complex, and multinational organizations. Mid-tier firms such as Grant Thornton, RSM, and BDO serve mid-market companies, often at lower fees.
Big 4 premium pricing is justified mainly by regulatory requirements, global reach, and investor-facing brand value. For private companies without global needs, a qualified regional firm often delivers equal or better value.
How do Big 4 audits differ from mid-tier audits?
The standards and independence rules are the same, but the Big 4 offer global platforms and scale. Mid-tier firms often offer more partner access.
Therefore, compare methodology, independence safeguards, and the team assigned to your audit.
Who are the top accounting firms after the Big 4?
RSM, Baker Tilly, BDO USA, CBIZ, Grant Thornton, Forvis Mazars, and Crowe are among the largest firms after the Big 4.
Grant Thornton Advisors agreed in July 2026 to acquire CBIZ, which would make it the fifth-largest US firm.
Should a small business hire a Big 4 firm?
Usually not, because Big 4 pricing and scale suit large, complex organizations.
Instead, a mid-tier firm or a CPA-led boutique often gives small businesses better value and more partner access.
How are the Big 4 using AI?
All four are embedding AI into audit, tax, and consulting work.
PwC invested $3 billion in FY2026, and KPMG plans about $4.2 billion by 2026. EY reported 49% growth in AI services sales.
Are the Big Four one company?
No. Each is a network of legally separate member firms that share a brand and standards.
For example, Deloitte US and Deloitte Australia are separate legal entities.
How many people work at the Big 4?
More than 1.5 million people work at the four firms.
Specifically, Deloitte has nearly 500,000, EY about 415,000, PwC about 370,000, and KPMG about 276,000.
What are the top 4 accounting firms’ combined revenues?
The top 4 accounting firms earn about $231 billion combined: Deloitte ($74.5B), PwC ($60.2B), EY ($57.0B), and KPMG ($39.8B).
Figures use FY2026 for Deloitte, PwC, and EY, and FY2025 for KPMG. Deloitte has led by revenue for several years, helped by its consulting scale.
Final Thoughts
The Big 4 accounting firms are not simply large accounting practices. They are professional services organizations that shape how the largest companies report their finances, manage risk, plan acquisitions, and transform operations.
For finance professionals, understanding the Big 4 is foundational knowledge. Businesses that know each firm’s strengths, and when a specialist fits better, make better decisions.
At Expertise Accelerated, our CPA-led team works alongside Big 4 firms, regional CPA firms, and internal finance teams. We provide accounting, financial reporting, and CFO advisory services to small and mid-market businesses.
Schedule a free consultation with Expertise Accelerated to find the right level of accounting support for your business.
