What Mid-size Accounting Firms Can Learn From The Big 4

published on 24 November 2023

Determining the "best" accounting firms in the world is no easy task. There are several key criteria to evaluate:

Client Satisfaction and Retention

High client satisfaction and retention rates demonstrate an accounting firm's ability to provide excellent service and build strong, lasting relationships. Firms like Ernst & Young and Deloitte are renowned for sky-high client satisfaction scores based on factors like responsiveness, industry knowledge, technology solutions, and value delivered. By focusing intensely on the client experience, the top firms in the world earn trust and loyalty year after year.

Industry Awards and Recognition

Leading industry awards like INSIDE Public Accounting's Best of the Best and Vault's annual accounting surveys signify peer validation of an accounting firm's talent, innovation, and leadership. Firms recognized with these awards, such as RSM US and BDO, demonstrate exceptional service and performance at scale based on both objective metrics and peer review.

Breadth and Quality of Services

Beyond core audit and tax offerings, the world’s premier accounting firms provide diverse, high-value services like M&A advisory, risk consulting, outsourcing, and regulatory support. Firms invest heavily in emerging service lines both organically and through acquisitions. KPMG offers particularly wide-ranging capabilities, from blockchain solutions to environmental/social/governance (ESG) reporting.

Investment in Innovation

Cutting-edge firms pour resources into emerging technologies like artificial intelligence, advanced data analytics, and cloud-based platforms to serve evolving client needs. PwC stands out with over $3 billion invested annually into developing innovative new services and solutions powered by leading-edge technologies.

Global Capabilities and Reach

For major multinational companies, seamless global capabilities spanning different regulatory environments are essential. Firms like Deloitte, EY, and KPMG have established themselves as powerhouses, leveraging vast global footprints and local expertise to simplify complex international needs.

Taken together, these criteria offer a holistic view into the world’s premier accounting firms based on client perceptions, peer validation, breadth of services, innovation, and global delivery capabilities. While size and brand strength play a role, client impact and value generation ultimately determine the cream of the crop.

What is the world's top accounting firm?

The world's top accounting firm is often considered to be one of the "Big Four" accounting firms: Deloitte, PwC, EY, or KPMG. These firms provide a comprehensive range of accounting, auditing, tax, consulting, risk advisory, and financial advisory services worldwide.

When evaluating the world's top accounting firm, key criteria include:

  • Revenue: The Big Four firms each generate over $30 billion in annual revenue. Deloitte leads with over $59 billion.

  • Number of employees: The Big Four employ hundreds of thousands of professionals globally. Deloitte again tops the list with over 450,000 employees.

  • Industry recognition: The Big Four dominate industry rankings and awards for top accounting firms. They are consistently rated highly for talent, innovation, leadership, and market impact.

  • Breadth of services: From auditing to mergers and acquisitions, the Big Four offer end-to-end support across accounting, finance, consulting, and more.

While other exceptional accounting firms exist, Deloitte edges out its Big Four peers as the world's current top accounting company based on these criteria. Their unparalleled global reach, comprehensive services, industry thought leadership, talent pool depth, and consistent innovation and growth set them apart.

However, all of the Big Four demonstrate exceptional expertise, experience, and authority that builds trust with clients worldwide. They set the standard for quality in accounting and shape the industry's future.

What are the top 3 accounting firms?

The largest accounting firms in the world, often referred to as the "Big Four", are Deloitte, PwC, EY, and KPMG. These global professional services networks lead the industry in revenue, number of clients, and recognition.

What sets the Big Four apart is:

  • Their massive global reach, with offices and clients spanning over 150 countries

  • Offering a comprehensive suite of accounting, auditing, tax, consulting, and financial advisory services

  • Employing over 1 million staff worldwide

  • Generating annual revenues over $100 billion+

While there are many exceptional accounting firms worldwide, the Big Four have cemented themselves as the premier global leaders in the accounting industry. Their scale, expertise, brand reputation and focus on quality make them the dominant force shaping the future of accounting.

Businesses that work with the Big Four can leverage their vast global resources and extensive industry knowledge. For an organization looking to grow globally or undertake complex accounting challenges, partnering with a Big Four firm can provide significant strategic and operational advantages.

Who are the Big 4 in the accounting world?

The Big Four accounting firms are Deloitte, Ernst & Young (EY), PricewaterhouseCoopers (PwC), and Klynveld Peat Marwick Goerdeler (KPMG). They are considered the top accounting firms in the world due to their global reach, high revenue, prestigious clientele, and wide range of services.

Key Facts About the Big Four Accounting Firms

  • They audit over 80% of public companies in the US and dominate the industry

  • Combined global revenue over $100 billion

  • Employ close to 1 million accounting professionals worldwide

  • Offer services beyond auditing like consulting, tax, transactions, risk, and legal advisory

The Big Four have established themselves as leaders in the accounting industry through their commitment to quality, global scale and reach, and breadth of services. When companies think of the best accounting firms in the world, the Big Four invariably come to mind.


What are the top 4 accounting firms?

The "Big Four" refers to the four largest public accounting firms in the world:


Founded in 1845, Deloitte is the largest professional services network in the world. With headquarters in London, Deloitte operates in over 150 countries and territories, providing audit & assurance, consulting, financial advisory, risk advisory, and tax & legal services.

In 2022, Deloitte had over 415,000 employees and generated record revenues of $59.3 billion. Known for its prestigious consulting arm and provision of services across virtually all industries, Deloitte is widely recognized as the number one accounting firm globally.

PricewaterhouseCoopers (PwC)

With headquarters in London, PwC is the second largest professional services firm in the world. Founded in 1849, PwC specializes in assurance, advisory, tax and legal services.

In FY22, PwC posted record global revenues of $51.6 billion with over 328,000 employees serving clients across 155 countries. Ranking just behind Deloitte based on revenue, PwC continues to cement itself as an undisputed leader in accounting and professional services.

Ernst & Young

Operating as EY since 2013, Ernst & Young is one of the "Big Four" accounting organizations. Headquartered in London with over 312,000 employees, EY provides assurance, consulting, strategy, tax and transaction services around the globe.

In FY22, EY generated worldwide revenue of over $45.4 billion, serving clients across over 150 countries. EY is recognized as an innovative, technology-driven firm and trails just behind Deloitte and PwC in terms of global revenue among accounting firms.


Headquartered in Amstelveen, Netherlands, KPMG is a global professional services firm focused primarily on audit, tax and advisory services. Founded in 1987, KPMG operates in over 150 countries with more than 236,000 employees worldwide.

In FY22, KPMG posted record global revenue of $32.1 billion. As one of the "Big Four", KPMG continues to cement itself as a leading global name in accounting and professional services, though does trail the "Big Three" in terms of revenue and global reach.

The Pinnacle of Excellence: Big 4 Accounting Firms

We examine the Big Four accounting firms - Deloitte, PwC, EY, and KPMG - which hold the largest global market share and demonstrate leading performance across key evaluation criteria.

Deloitte Touche Tohmatsu: Leading the Charge

With over $50 billion in global revenue, Deloitte leads the industry in scale and breadth of services offered to clients worldwide. As the largest professional services network, Deloitte leverages its vast global reach and local expertise to provide premier audit, consulting, tax, and advisory services.

Notable strengths include:

  • Industry-leading audit practices, upholding high standards of quality and integrity

  • Cutting-edge technologies like AI and blockchain integrated into service offerings

  • Deep bench of over 330,000 professionals bringing specialized skills and experience

  • Global connectivity through member firms in over 150 countries

By revenue, global talent pool, and diversity of services, Deloitte stands atop as a paragon of excellence for accounting firms worldwide.

PricewaterhouseCoopers (PwC): Consistency and Quality

PwC garners top rankings for audit quality and consistency, aided by heavy investments in innovative technologies like AI and blockchain. As the second-largest professional services network globally, PwC leverages its scale and resources to deliver premier quality across assurance, advisory, tax, and other offerings.

Key strengths include:

  • Top ratings for audit quality based on PCAOB inspection reports

  • Cutting-edge technologies like AI and blockchain integrated into service offerings

  • 284,000 professionals focused on consistency and continuous improvement

  • Strong global presence in 155 countries

With its steadfast commitment to quality and consistency, PwC has cemented its stature among the world's leading accounting firms.

Ernst & Young (EY): Beyond the Numbers

EY shows strength across advisory and consulting services, demonstrated by peer-validated awards, robust growth, and high client retention rates. While also excelling in assurance and tax offerings, EY stands out for advisory services spanning cybersecurity, strategy, transactions, transformation and more.

Standout attributes include:

  • Over 30% growth in global advisory revenues from 2020 to 2021

  • #1 in ALM Vanguard Leader positions across multiple advisory services

  • 321,000 professionals providing both breadth and depth of capabilities

  • Global connectivity through member firms in over 150 countries

With a balanced portfolio across service lines and peer-recognized excellence in advisory, EY continues to exemplify global leadership.

KPMG International: Digital Frontiers

KPMG offers leading capabilities in highly-specialized areas like cybersecurity and digital transformation advisory crucial for modern businesses. While strong across the board in traditional accounting services, KPMG leans into emerging frontiers like ESG advising and cloud migration strategy.

Areas of excellence:

  • Cutting-edge expertise in digital transformation, cloud, cybersecurity and ESG

  • Strategic investments and partnerships focused on advanced technologies

  • Over 236,000 professionals with specialized skills and certifications

  • Robust presence in 147 countries globally

By combining digital-first talent and offerings with global scale and resources, KPMG pushes the boundaries of accounting services into the future.

Recognizing the Top 100 Accounting Firms of 2023

Accounting firms range in size but share a common trait - they're essential partners for enabling business success. As we move through the current year, we spotlight the top firms that made the 2023 list, showcasing their core strengths.

Championing Quality: The Top 20 Audit Firms in the World

Audit and assurance are critical components of financial health. The top 20 audit firms worldwide have earned top marks by prioritizing audit quality and maintaining high ethical standards. These big 8 accounting firms invest heavily in technology, cybersecurity, specialized industry knowledge and regular staff training to conduct reliable, independent reviews.

Clients of the big 4 accounting firms - Deloitte, EY, KPMG and PwC - benefit from their vast global resources and expertise across all industries and sectors. Beyond these giants, firms like BDO, Grant Thornton, and RSM use strong local networks to consistently deliver for mid-size businesses.

No matter their structure, the top accounting firms recognize that an audit done right fosters transparency and trust with stakeholders. This gives leadership crucial insights to strengthen strategy and operations. For any organization, partnering with a reputable audit firm provides assurance and value beyond compliance.

Masters of Their Craft: The Top 50 Accounting Firms

The top 50 accounting firms consist of both mammoth enterprises and specialized shops united by excelling in their service offerings. These firms exhibit extensive expertise, industry insight, and adaptability to ever-changing regulations and market landscapes.

Many focus on core services like audit, tax, risk advisory, and outsourced accounting. Larger firms have global reach, while smaller outfits develop regional niches and local relationships. Others concentrate on key verticals like financial services, healthcare, real estate, and technology - assembling industry dedicated teams.

Common across the spectrum is helping clients tackle complex accounting challenges and generating actionable intelligence to improve performance. Continuous innovation also enables the top 50 accounting firms to provide vital guidance on emerging issues like climate risk, diversity initiatives, and supply chain resilience.

Niche Specialists: Mid-Size Accounting Firms Making Waves

Beyond heavyweights, mid-size accounting firms are making waves by tailoring services to specialized needs. These firms carve out niches in areas like sustainability reporting, employee benefit plans, and forensic accounting. Others build deep expertise in key sectors such as manufacturing, transportation, and professional services.

These mid-size accounting firms use their focused approaches to deliver exemplary client service. Developing concentrated industry and subject matter strengths allows them to dive deep into the pain points and opportunities facing customers. They translate technical guidance into targeted recommendations that drive strategic goals - with an individualized touch larger firms struggle to match.

Many boutique firms also boast partners and talent hailing from the Big 5 accounting firms. They replicate the quality of top-tier organizations while avoiding mammoth overheads that inflate client fees. These close-knit teams offer the technical bench of bigger names with the care and flexibility smaller shops pride. For niche needs or specialized industries, mid-size niche players are punching above their weight.

Evaluating the Best Accounting Firm for Your Needs

When looking to engage an accounting firm, it's important to consider several key factors to ensure you find the right fit for your business needs. Assessing criteria such as industry specialization, global reach, innovation, cultural alignment, and client satisfaction can help determine which firm is best equipped to provide the services and guidance to support your organization's growth and success.

Align Industry and Geographic Focus Areas

Seeking an accounting firm with proven experience and recognition in your specific industry vertical and geographic markets is key. Firms that dedicate practices to certain sectors often have valuable insider perspective and technical knowledge that translates to actionable insights for clients. They also likely have established professional networks and relationships with stakeholders in those segments that facilitate business development.

Similarly, choosing a firm with an established presence in your operating countries and regions provides localized tax, regulatory and compliance support to avoid missteps as you expand. Assess options that offer both niche industry expertise as well as geographic reach to best position your financial operations at home and abroad.

Assess Breadth of Services Offered

Determine whether the accounting firm provides the breadth of services your business needs, both now and as you scale. Beyond assurance and tax, many firms also offer advisory services in transactions, valuations, technology implementations, cybersecurity, operational excellence, and more.

Having access to integrated specialties in areas like M&A, systems integration, and management consulting under one roof delivers more holistic guidance as well as operational efficiencies. Identify firms equipped to provide end-to-end support today and in the future.

Evaluate Investments in Innovation

Look for indications that firms are evolving their delivery models and leveraging emerging technologies to better serve clients. Examples include applying cloud computing, data analytics, machine learning, and robotic process automation to conduct audits, uncover insights faster, increase efficiency, and enhance transparency.

Firms doubling down on innovation provide higher-quality outcomes and add more strategic value at lower costs. They also exhibit an understanding of modern challenges and priorities, signaling better positioned to collaborate on growth initiatives.

Consider Cultural Fit and Communication

Vet shortlisted accounting firms to ensure their work styles and values fit your company’s culture for optimal alignment. Look for their commitment to accountability, transparency, collaboration, and integrity. Expect clear, proactive communication from leadership regarding objectives, methodologies, critical assumptions, and explanatory rationales behind recommendations.

Firms that align with your operating philosophy and norms and keep clients closely looped in at every stage of engagements establish productive long-term relationships and help achieve strategic targets.

Compare Client Satisfaction and Retention

Pay close attention to accounting firms with demonstrable track records of keeping clients highly satisfied, as this signals they best understand client priorities and stick to them diligently. High client retention rates also indicate reliability in delivering consistent quality over the long term in a trusted partner relationship.

These should rank among the most important evaluation criteria as they reflect actual performance and the ability to maintain excellence at scale over time. Leverage client testimonials and published survey results to compare satisfaction metrics.

By weighing industry specialization, geographic presence, service breadth, innovation, culture, and satisfaction indicators, you can determine the best accounting firm for supporting your growth journey. Selecting the right financial advisor positions your business for current and future success.

Synthesizing the Qualities of Elite Accounting Networks

In summary, the world's top accounting firms demonstrate strengths across client satisfaction, industry leadership, global reach, innovative capabilities, specialized services, and talent development.

Key Takeaways for Business Leaders and Finance Professionals

The foremost accounting firms worldwide exhibit excellence across several key areas:

  • Client satisfaction: Prioritizing client needs and delivering high-quality services leads to strong client relationships and referral business. Firms like Deloitte, PwC, and EY perform well here.

  • Industry leadership: Thought leadership and pioneering new methods (e.g. blockchain, AI) cements status as an authority. KPMG and Deloitte have made big strides.

  • Global reach: Capabilities across major markets like the Americas, APAC, and EMEA allow serving multinational clients. The Big Four accounting networks have the greatest international coverage.

  • Innovative capabilities: Investing in emerging technologies and new service offerings demonstrates a future-ready approach. Regional stars like RSM and Grant Thornton are bold here.

  • Specialized services: Deep expertise in key verticals (technology, healthcare) or offerings (M&A, forensics) creates distinct value. Boutiques outperform in focused domains.

  • Talent development: Commitment to upskilling staff and providing growth opportunities aids in attraction and retention. The Big Four do this consistently well.

When selecting an accounting partner, ensure you evaluate firms thoroughly on relevant criteria: industry specialization, technical capabilities, cultural fit, innovation track record, global reach, and more. Though the Big Four are dominant globally, excellent firms exist at other tiers too – know your specific needs.

Related posts

Read more