Big 4 Public Accounting Firms

What Big 4 Public Accounting Firms does

The Big 4 Public Accounting Firms comprise Deloitte, Ernst & Young (EY), PricewaterhouseCoopers (PwC), and KPMG — the four largest privately held professional services networks in the world, which emerged in their current form from mergers in the late 1980s and 1990s. They collectively generated $157B+ in FY 2023 revenue (Deloitte $65.8B, PwC $53.1B, EY $49.4B, KPMG $36.4B) and employ more than 1.3 million professionals across 150+ countries, with the Big 4 auditing over 80% of all US public companies and handling 99% of public-company sales. Their core services span audit and assurance, tax strategy and compliance, advisory and consulting (risk, technology transformation, cybersecurity, forensics, ESG), and financial advisory, delivered through dedicated enterprise account teams and partner-led engagements.

Underlying delivery is increasingly enabled by cloud computing, analytics, and artificial intelligence, with selective strategic technology alliances such as KPMG's partnership with BlackLine Systems to embed record-to-report automation. The revenue model is professional services fees billed against multi-year enterprise engagements, with pricing quoted per engagement based on scope, complexity, client size, and geography rather than standardized rates. GTM motion is enterprise field sales through direct account teams, supplemented by professional referrals, thought leadership, and university recruiting pipelines that feed the talent engine underpinning the firms' service delivery.

The associated web property big4accountingfirms.org is a privately held informational portal that publishes firm profiles, career guidance, accounting-school rankings, and reviews of CPA exam preparation products (Becker, Gleim, UWorld, Surgent, Lambers), monetized in part through affiliate partnerships. The portal is not the operating entity of the four firms; it is a content and lead-generation resource adjacent to the Big 4 brand umbrella.

Name

Big 4 Public Accounting Firms

Legal name

Big 4 Accounting Firms

Website

https://big4accountingfirms.org

Company type

Private

Founded year

1989

Operating status

Operating

Short description

The Big 4 Public Accounting Firms (Deloitte, EY, PwC, KPMG) are privately held professional services networks delivering audit, tax, advisory, and consulting services to large enterprises, governments, and financial institutions worldwide, with combined FY 2023 revenue of $157B+ and 1.3M+ professionals across 150+ countries.

Ownership category

akta.pro rank

Product category

Accounting and Professional Services

NAICS

Accounting, Tax Preparation, Bookkeeping, and Payroll Services (54121), Professional, Scientific, and Technical Services (541)

SIC

Services-Engineering, Accounting, Research, Management (8700)

akta.pro primary industry

Financial Planning & Analysis Support (Budgeting, Forecasting, Management Reporting) (BPAAAGAJ)

Keywords

• Audit assurance services
• Tax advisory consulting
• Professional services network
• Financial advisory services
• Management consulting

Headquarters

HQ city

New York

HQ country

United States

HQ region

North America

Offices3 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Technology or R&D, Operations, Infrastructure, Marketing or Sales

Revenue model

1. Audit and Assurance Services: Statutory audits, internal audits, and assurance services for public and private companies
2. Tax Advisory Services: Tax strategy, planning, compliance, and consulting services across global jurisdictions
3. Advisory and Consulting: Risk consulting, financial advisory, technology transformation, forensics, cybersecurity, and management consulting services

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels4 records

Core offering

The Big 4 are professional services networks that sell audit and assurance, tax advisory, management consulting, risk advisory, financial advisory, technology transformation, cybersecurity, forensics, and ESG/sustainability services to large enterprises, governments, and financial institutions worldwide. They collectively employ 1.3M+ professionals across 150+ countries and audit over 80% of all US public companies. Revenue is generated primarily through professional services fees billed on multi-year contracts.

Product overview

The Big 4 Public Accounting Firms information portal provides comprehensive coverage of the four largest professional services networks (Deloitte, EY, PwC, and KPMG) and serves as a hub for CPA exam preparation resources. The platform features five branded CPA review course products: Becker CPA Review (premium course with AI Newt assistant), Gleim CPA Review (practice-heavy with SmartAdapt), UWorld CPA Review (visual learning with SmartPath), Surgent CPA Review (budget-adaptive with ReadySCORE), and Lambers CPA Review (traditional exam prep). These products are reviewed, compared, and promoted as affiliate partnerships rather than being a unified software platform.

Differentiator

Problem solved

Functional benefit

Products and services

• Becker CPA Review
• Gleim CPA Review Practice-intensive CPA exam prep course built around a 12,000+ MCQ and 1,600+ TBS question bank, with SmartAdapt adaptive learning and short video lessons for efficient study. Designed for CPA candidates who prefer question-volume-driven preparation.
• UWorld CPA Review Visual learning-focused CPA exam prep course combining Roger CPA, Wiley, and UWorld content, with SmartPath Predictive Technology, 1,400+ video lectures, and 9,000+ MCQs with detailed answer explanations. Targeted at CPA candidates who prefer visual and explanation-rich study.
• Surgent CPA Review Budget-friendly adaptive CPA exam prep course featuring ReadySCORE exam-readiness tracking, 9,000+ MCQs, and predictive AI that generates personalized study plans based on student performance. Aimed at cost-conscious CPA candidates.
• Lambers CPA Review Traditional CPA exam preparation course with 45+ years of history, offering study materials, video lectures, simulations, audio courses, and a money-back guarantee for students who fail the same exam twice. Targeted at CPA candidates who prefer established, traditional study formats.
• Audit and Assurance Services Statutory audits, internal audits, and assurance services delivered to public and private companies worldwide by the Big 4 member firms. Audits over 80% of all US public companies.
• Tax Advisory Services Tax strategy, planning, compliance, and consulting services delivered across global jurisdictions for multinational corporations, financial institutions, and other large organizations.
• Advisory and Consulting Services Risk consulting, financial advisory, technology transformation, forensics, cybersecurity, and management consulting services delivered to enterprise, government, and institutional clients globally.

Quantifiable outcome

• The Big 4 audit over 80% of all US public companies
• +2 more outcomes

Named customers4 records

Segments5 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

Two partnerships are on record, tiered major and core.

• Booz & CompanymajorStrategic or Co-development Partner · 23 December 2013PwC completed its merger with Booz & Company, a medium-sized consulting firm, expanding PwC's consulting capabilities and global reach.
• BlackLine SystemscoreStrategic or Co-development PartnerKPMG's strategic alliance with BlackLine Systems provides cloud-based record-to-report technologies. Together they help clients apply controls throughout accounting cycles using financial management solutions.

Scale indicators14 records

Recent moves6 records

Expansion highlights6 records

Direct peers

• BDO International: BDO is the 5th largest global accounting network, directly comparable to the Big 4 in offering audit, tax, and advisory services to mid-market and large corporate clients worldwide. It competes head-to-head with the Big 4 in the upper-mid-market segment where regulatory and complexity requirements overlap.
• Mazars: Mazars is an international audit, tax, and advisory firm operating across 90+ countries, comparable in service mix and client profile to the Big 4 (excluding the very largest FTSE/Fortune 500 audits). It competes directly for multinational mid-market audit and advisory work.
• Grant Thornton International: Grant Thornton is the 6th largest global accounting network, offering audit, tax, and advisory services with comparable client profiles to the Big 4's middle-market and large private company segments. It competes directly for the same multinational audit and advisory engagements.
• RSM International: RSM is a top-10 global accounting network focused on middle-market companies, providing audit, tax, and consulting services comparable in scope to the Big 4's mid-market service lines. It serves as the most direct competitor for cross-border middle-market engagements.
• Baker Tilly International: Baker Tilly is a top-10 global accounting network offering audit, tax, and advisory services with comparable mid-market positioning. It is one of the strongest non-Big 4 alternatives for multinational mid-market audit and advisory work, making it a direct peer for the Big 4's middle-market service lines.
• Crowe Global: Crowe Global is a top-10 international accounting network offering audit, tax, and advisory services with a comparable mid-market focus. It directly competes with the Big 4 for mid-market audit engagements and serves as a viable alternative for clients seeking non-Big 4 assurance providers.

Broad incumbents

• McKinsey & Company: McKinsey is the world's largest management consulting firm, competing with the Big 4's advisory/consulting practices (particularly Deloitte and PwC) for senior-level strategy and operations engagements with Fortune 500 clients. Overlap is concentrated in advisory and consulting rather than audit.
• Accenture: Accenture is a global professional services firm with overlapping capabilities in technology transformation, consulting, and managed services that compete directly with Deloitte, PwC, and EY's consulting practices. It is a major incumbent in the same broader professional services category.
• Bain & Company: Bain & Company is a top-tier global management consulting firm that competes with the Big 4's advisory arms for senior strategy engagements. While focused on consulting rather than audit, it operates in the same broader professional services space and serves overlapping Fortune 500 clients.
• Boston Consulting Group: BCG is a leading global management consulting firm that competes with the Big 4's advisory practices (especially Deloitte and PwC) for corporate strategy and transformation engagements. Like McKinsey and Bain, it overlaps in consulting rather than audit but serves the same enterprise client base.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights7 records

Customer concentration

• Xx.com/webfaction
• Facebookfacebook.com/webfaction
• LinkedInlinkedin.com/company/big-4-accounting-firms

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

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M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Big 4 Public Accounting Firms