What Is the Difference Between MBB and the Big Four?

Who Are the Big Three Consulting Firms?

The “Big Three” are the three leading global consulting firms, namely McKinsey, BCG, and Bain & Company. They are each other's biggest competitors and have competed for customers for decades. Their extensive client base, reputation for delivering high-quality consulting services and global network of top consultants sets them apart from other consulting firms in the industry.

McKinsey

Revenue: $15bn+

Employees: 38,000+

Offices: 144

Countries: 65

McKinsey was founded in 1926 and is widely recognized as one of the oldest, most prestigious, and most influential consulting firms worldwide. With more than 140 offices in 65 countries, McKinsey has a significant global presence and an expansive network that enables the consulting firm to serve clients from various industries on a global scale. 

What distinguishes McKinsey from other consulting firms? 

McKinsey’s recommendations and strategic guidance have a vast influence on corporate decision-making, government policies, and social initiatives. The company offers advisory services in different areas - from strategy to operations, organization, technology, marketing, and sustainability. Known for its deep industry expertise and thought leadership, McKinsey has established a strong reputation for its contributions to the business world. The consultancy conducts extensive research, publishes reports, and shares insights on critical business issues, trends, and new innovations. 

In order to develop innovative strategies and effective solutions, McKinsey emphasizes a close relationship with their clients. The consulting firm fosters a collaborative work environment and aims to understand the unique challenges of their clients in much detail. Knowledge sharing, brainstorming, and the exploration of different ideas and perspectives are a crucial aspect of McKinsey’s corporate culture. 

What kind of people does McKinsey hire? 

McKinsey seeks to attract top talent from diverse academic backgrounds and industries. The consulting firm hires individuals with exceptional problem-solving skills, analytical abilities, and leadership potential. Senior consultants guide and coach their junior colleagues and support them in their professional growth and development within the firm. Moreover, McKinsey provides comprehensive training and development programs to build up the consulting skills of their employees. They are credited with recruiting and developing some of the top business leaders in the world and have earned the nickname “The CEO Factory” as top executives from companies such as Facebook and Google have come from McKinsey.

Bain & Company

Revenue: $5.8bn+

Employees: 15,000+

Offices: 64

Countries: 39

Bain was founded in 1973 by Bill Bain and a group of BCG executives after a fallout with the incumbent BCG CEO, Bruce Henderson. Bill Bain and his team had generated more than 50% of BCG’s annual revenues and after disagreeing with several Bruce Henderson’s management decisions, they resigned and started their own consulting firm, taking many BCG clients with them.

The firm grew rapidly and began to focus on a business turnaround strategy, working closely with private equity investors (including their own spin-off, Bain Capital). Today private equity makes up a large proportion of Bain’s annual revenues. By now, the consulting firm has grown to an annual revenue of more than $5.8bn and has over 64 offices in 39 countries. 

What kind of projects is Bain & Company advised for? 

Bain & Company is regularly advised for driving successful turnarounds, launching new ventures, and guiding companies through periods of disruption. The consulting firm’s client portfolio ranges from startups to multinational corporations. A special focus is on the private equity sector with assistance from deal sourcing to commercial due diligence, portfolio management and investors’ exit. 

What is the corporate culture at Bain & Company like? 

Just as McKinsey and BCG, Bain emphasizes a strong corporate culture to attract talent from around the globe. Their employees are referred to as “Bainies” and the consulting firm promotes a highly collaborative work environment of mutual support and inclusion. Moreover, Bain's culture encourages entrepreneurial thinking and initiative. Consultants are empowered to take ownership of their work, drive innovation, and proactively seek new opportunities for growth. “Results, not reports” is one of the core values of the consulting firm and a strong hands-on mentality as well as a focus on tangible results are actively encouraged. 

BCG

Revenue: $12bn+

Employees: 21,000+

Offices: 90+

Countries: 50

The Boston Consulting Group (BCG) was founded in 1963 initially as the consulting arm of The Boston Safe Deposit and Trust Company in order to provide strategic advice to the bank's clients. Eventually, the employees purchased full ownership of the consulting practice and became BCG as it is known today. By now, BCG has over 90 offices in more than 50 countries. It is recognized as one of the leading consulting firms worldwide and provides clients with strategic advice to drive growth, optimize operations, and navigate the ever-changing business landscape. 

What is the focus of BCG? 

BCG’ focus is on strategic management consulting for organizations from various sectors, including financial services, industrial goods, retail, or the public sector. The consultancy is known for its innovative and forward-thinking approach, and delivery of tangible results. Projects are often in the fields of growth strategies, market analysis, organizational change, and operational efficiency. The Boston Consulting Group has a strong focus on helping their clients to navigate the digital landscape and develop digital strategies to leverage emerging technologies, improve customer experiences, and drive innovation in the digital era. 
The corporate culture at the Boston Consulting Group is based on five principles: “Bring insight to light”, “conquer complexity”, “drive inspired impact”, “lead with integrity”, and “grow by growing others”. Teamwork, mentorship, and coaching are fostered to help consultants develop their skills and reach their full potential.

Which kind of candidates does BCG look for? 

As a professional service firm, BCG seeks talented individuals to join the firm. The consultancy generally looks out for candidates with strong analytical and problem-solving skills, great communication skills, and leadership potential. While academic performance is essential, BCG also values individuals who have demonstrated personal drive and shown impact in their professional experiences. The consulting firm puts great importance on diversity and inclusion and seeks candidates from different backgrounds, academic disciplines and unique perspectives. 

Who Are the Big Four Consulting Firms?

The Big 4 is the name given to the four biggest accounting firms in the world. They are PricewaterhouseCoopers (PwC), Ernst & Young (EY), Klynveld Peat Marwick Goerdeler (KPMG), and Deloitte. All of them have grown to be multi-billion-dollar firms that employ hundreds of thousands of people across the globe. According to their own financial statements of 2022, they have a combined total revenue of nearly 190 billion dollars.

In recent years all four of these firms have accelerated their diversification into other professional services including Risk Assurance, Tax, Legal, and Consulting. They are regarded as one of the most reputable graduate employers and have been the training ground for many business leaders. 

All the Big Four have a significant global presence and serve clients across various industries. They are referred to as the Big Four as they are similar in revenue and workforce size and make up a major share of the global market for auditing, tax and advisory services. 

PwC

Revenue: $50bn+

Employees: 328,000+

Offices: 742

Countries: 152

PwC was formed in 1998 by the merger of two accounting firms with a history dating back to the 19th century: Coopers & Lybrand and Price Waterhouse.

Since the merger, PwC has expanded from its accountancy roots into other professional services, including consulting, law, and transaction advisory, and works on more transactions (acquisitions, mergers, and financing) than any other company in the world. Moving away from their accounting heritage, audit work is no longer the primary revenue stream for PwC and today they boast a rapidly growing consulting practice and the largest tax practice in the world.

What sets PwC apart from other consulting firms? 

PwC places a significant emphasis on technology and digital transformation services. The firm has made substantial investments in building its capabilities in areas such as cybersecurity, data analytics, artificial intelligence, and cloud computing. PwC's deep expertise in these fields enables them to guide clients effectively through complex digital transformations and harness the potential of emerging technologies.

With more than 328,000 employees worldwide, PwC serves clients in a wide range of industries and geographies. The company has always strived to work with the biggest and most established firms in the world. They state their purpose is to “Build trust in society and solve important problems” and this is shown by the high proportion of work with governments across the world and the continued focus on serving the world’s biggest with their suite of professional services.

The consulting firm has dedicated industry teams that focus on specific sectors, allowing them to offer tailored solutions and insights based on industry-specific knowledge and best practices. PwC produces a wealth of reports, studies, and publications on various business topics and trends. The consultancy is known for its robust research and thought leadership capabilities. 

Deloitte

Revenue: $59bn+

Employees: 412,000+

Offices: 100+

Countries: 130+

Deloitte was originally founded in London in 1845 but grew via M&A later in the 20th century with other accounting firms such as Haskins & Sells, Touche Ross, and Arthur Andersen. Uniquely, Deloitte was the only firm not to divest its consulting practice in the wake of the Sabine-Oxley legislation in the early 2000s. This appears to have been a shrewd move that is now paying dividends as Deloitte has successfully positioned itself as a digital transformation and product expert with the creation of Deloitte Digital. Consulting is Deloitte’s biggest revenue stream and is a key difference between themselves and the other Big Four firms.

By revenue, Deloitte is the biggest of the Big 4 boasting top-line revenue figures of over $59 billion - they have the most audit clients in the UK’s FTSE 100. The firm offers a wide spectrum of professional services to its clients from risk assurance to strategy consulting. They often sponsor major sporting events and even sponsored the summer Olympics in 2012. 

What is the purpose of Deloitte? 

Deloitte’s purpose is ‘To make an impact that matters. They are focusing their efforts on practical implementation and product operations for large organizations. These projects are worth millions of dollars each and position Deloitte well for sell-on work in the future when organizations look to digitize other parts of their business.

However, the consulting practice of Deloitte does not only cover strategy and operations but also global business consulting. This includes assisting clients in expanding their operations internationally, navigating complex regulatory environments, managing cross-border transactions, and optimizing global supply chains.

Deloitte actively explores emerging technologies, such as artificial intelligence, robotics, and blockchain, and advises clients on how to leverage these advancements to drive business growth and transformation. Deloitte's innovation initiatives, research centers, and strategic partnerships enable the consulting firm to provide their clients with the newest trends and insights. 

EY

Revenue: $45bn+

Employees: 365,000+

Offices: 700+

Countries: 150+

EY is the result of several mergers between UK and US accounting firms over the last century. The key three mergers were between Whinney, Smith & Whinney (UK), Ernst & Ernst (US), and Arthur Young & Co. (US). These mergers resulted in a new company named Ernst & Young.

Notably, Ernst and Young planned to merge with rival KPMG in 1997, but the deal fell through due to antitrust issues, client opposition, and cost. The company rebranded as EY in 2013 and also acquired Parthenon consulting to expand its consulting practice.

Today, the US firm of EY is the most successful of their network, serving more firms in the S&P 500 than any of the other Big Four firms. In the UK they serve as many as PwC but less than Deloitte.

EY’s purpose is ‘Building a better working world. Similarly, to the other Big 4 firms, they have expanded into other professional services. Recently EY was named a global leader in digital business transformation putting them in direct competition with companies such as Accenture, Capgemini, and IBM.

What distinguishes EY from other consulting firms? 

EY is closely involved in the start-up ecosystem and collaborates with many incubators, and accelerators. With the prestigious “EY Entrepreneur of The Year®” award, the consulting firm recognizes entrepreneurial achievements, and provides startups a platform to showcase their ideas and achievements. Moreover, EY organizes the EY Start-up Challenge, which includes a series of workshops, mentoring sessions, and networking opportunities to support founders to develop a sustainable business strategy.

When it comes to their workforce, EY has set ambitious diversity and inclusion goals, such as achieving gender parity in its leadership ranks and increasing the representation of underrepresented groups across the organization. The consulting firm's efforts have earned recognition, including being named as one of the "Best Companies for Diversity" by Forbes.

KPMG

Revenue: $35bn+

Employees: 265,000+

Offices: 650+

Countries: 147

The smallest of the Big Four by revenue is KPMG. The accounting firm has roots in the Netherlands, the United Kingdom, and the United States. Starting in 1815, the company grew via several mergers and acquisitions. Still, it was in 1979 when the first signs of KPMG appeared when three firms merged: Klynveld Kraayenhof & Co. (NL), McLintock Main LaFrentz (UK / US), and Deutsche Treuhandgesellschaft (DE) formed KMG (Klynveld Main Goerdeler). Then in 1987, the first ‘mega merger’ of accounting firms happened when KMG merged with Peat Marwick to form KPMG.

Today, KPMG has a vast network of member firms and operates in over 145 countries. The consulting firm provides clients across industries and borders with professional services in the fields of audit, tax, and advisory. Their consulting services range from classical management consulting to digital transformation, technology consulting, deal advisory, risk consulting, and much more. The consultancy offers a comprehensive range of professional services across various disciplines.

What is the purpose of KPMG? 

KPMG’s purpose is to ‘Inspire confidence and empower change. They see themselves as long-term partners with their clients across all areas of their business and KPMG want their employees to be proud of the work they do. They compete on all service fronts with the rest of the Big Four and the main contributing factor to their smaller size is a result of the other mergers and acquisitions that the other firms undertook rather than quality or reputation.

To foster innovation, KPMG has established several Insights Centers around the world. These centers serve as innovation hubs where professionals can collaborate, experiment with emerging technologies, and develop cutting-edge solutions to meet client needs. The consulting firm regularly publishes research reports, industry analysis, and white papers and has built a network of startups, academia, and technology partners to provide their clients with the latest insights and trends.

What Do the Big Three (MBB) Consulting Firms Do? 

The big three consulting firms McKinsey, BCG, and Bain (MBB) all offer the same services to their clients and have competed against one another for decades. They are first and foremost strategy consultancies. Strategy consultancies work with senior-level executives on their most important challenges. This is because they have knowledge of how other competitors have approached the challenge, can devote 100% of their time to the problem, and will consider every possibility.

Overall, strategy consultancies play a critical role in helping organizations shape their future direction, develop competitive strategies, and navigate complex business environments. This involves analyzing market dynamics, competitive landscape, and internal capabilities to identify growth opportunities, define strategic objectives, and determine the best course of action.  

Working at one of the Big Three consultants is considered to be one of the most lucrative and reputationally beneficial career moves you can make. This is because they are working with companies and governments at the highest level and demand a lot of their staff to produce quality results.

The type of work that the Big Three work on are often times cost reduction programs, operational efficiency, market-entry, and new product launches. All of these are unique one-off problems for a business, but all are focused on increasing profits and revenues.

What Do the Big Four Consulting Firms Do? 

The Big Four are all accounting firms in origin but have expanded into other areas in recent years. They are best known for their audit work which is required for companies over a certain size in order to verify their financial statements and provide assurances to investors and tax authorities that the company is complying with their obligations.

In the early 2000s, the Big 4 expanded their services into other professional services such as consulting and law but following controversy over the independence of firms providing advisory services to clients they audited, PwC, EY, and KPMG all divested these services. Deloitte was the only firm to retain its consulting practice.

However, since 2010 consulting has been the primary driver of growth for these firms. They all now offer audit, tax, risk assurance, consulting, and transaction services to their clients. For PwC, the biggest tax advisor in the world, consulting now generates as much revenue as their tax practice.

EY, Deloitte, and PwC have also all acquired strategy consulting firms meaning that they now compete directly with the Big 3. The Big 4 play an instrumental role in empowering businesses across industries and with their global presence, and industry expertise they continue to be trusted partners for businesses worldwide.

What Are the Differences Between the Big Three and the Big Four Consulting Firms? 

Differences Between the Big Three (MBB) and the Big Four Consulting Firms

The key differences between the Big Three (McKinsey & Company, Boston Consulting Group, and Bain & Company) and the Big Four consulting firms (Deloitte, PricewaterhouseCoopers (PwC), Ernst & Young (EY), and KPMG) lie in their areas of service offerings, client base, organizational structures, and reputation. Let’s take a look at the distinctions: 

How Do the Service Offerings Differ between the Big Three and the Big Four Consulting Firms?  

The Big Three consulting firms primarily focus on strategy consulting, providing strategic advice to organizations across various industries. They are known for their expertise in strategy development, operational improvement, and organizational transformation and help clients with high-level strategic initiatives.

The Big Four consulting firms offer a broader range of services beyond consulting. While they have consulting practices, their core services also include audit and assurance, tax, and other advisory services such as risk consulting and financial advisory.
 

Which kind of Clients Do the Big Three and The Big Four Consulting Firms advise? 

The Big Three predominantly serve large multinational corporations, government entities, and high-profile organizations. They often work with C-suite executives and senior leadership teams to address complex strategic issues.

The Big Four have a more diverse client base that includes not only large corporations but also small and medium-sized enterprises (SMEs), government agencies, non-profit organizations, and individuals. They cater to a broader spectrum of industries and sectors.

How Does the Organizational Structure Differ between the Big Three and the Big Four Consulting Firms?  

The Big Three consulting firms operate as partnerships, with a strong focus on their consulting practices. They typically have a relatively smaller number of partners, and their organizational structure tends to be more streamlined.

The Big Four consulting firms are multi-disciplinary organizations with a matrix-like structure. They have larger partner networks and operate across multiple service lines, including audit, tax, and advisory. Their structure allows for collaboration and cross-functional expertise.

Do the Big Three Have a Better Reputation Than the Big Four? 

The Big Three have a longstanding reputation as prestigious and elite consulting firms. They are often perceived as industry leaders and are highly sought after by top-tier talent and clients.

The Big Four are recognized globally for their accounting and professional services, including consulting. While their consulting practices are strong, they may not have the same level of exclusivity and perception of being solely strategy-focused as the Big Three.

After all, it’s important to keep in mind that these differences are generalizations and there may be overlaps and exceptions. The consulting industry is dynamic, and firms continuously evolve their service offerings to adapt to changing market demands and client needs.

5.2 Similarities Between the Big Three (MBB) and the Big Four Consulting Firms

While the Big Three (McKinsey & Company, BCG, and Bain) and the Big Four consulting firms (PwC, Deloitte, EY, and KPMG) have their distinct characteristics, there are also several similarities that can be observed:

Global Presence: 

Both the Big Three and the Big Four have a strong global presence with offices in multiple countries. They operate on a global scale and serve clients across various regions and industries.

Corporate Structure:

Both groups have similar corporate structures and hence career paths and organizational models. They are partnership firms whereby each partner is responsible for winning work and takes home a share of the profits at the end of the year.

Consulting Services: 

Whilst there has been some level of competition between the Big 3 and Big 4 for over 20 years, it was when EY, Deloitte, and PwC all acquired strategy consulting firms (some of the Big 3’s competitors) that they began to offer the same services and compete more often for work.

Talent Pool: 

Both the Big Three and the Big Four attract top talent from prestigious universities and professionals with diverse backgrounds. They strive to maintain a high-caliber workforce with exceptional analytical, problem-solving, and industry-specific skills.

Collaborative Approach: 

Both the Big Three and the Big Four emphasize collaboration and teamwork within their organizations. They foster a culture of knowledge sharing, cross-functional expertise, and collaboration across different service lines or practices.

Client-Centric Focus: 

Both groups prioritize client satisfaction and strive to deliver tailored solutions that meet their clients' unique needs. They prioritize understanding clients' businesses, industry dynamics, and challenges to provide valuable insights and recommendations.

While there are similarities among them, it's important to note that each firm within the Big Three and the Big Four has its unique strengths, focus areas, and organizational culture. The specific services, industry expertise, and market positioning of each firm may vary, allowing clients to choose the best fit based on their specific needs and requirements.

What Is Better - Working for One of the Big Three or One of the Big Four Consulting Firms? 

Receiving an offer from any of the Big Three or Big Four consulting firms is something to celebrate and a great achievement as the graduate application process for all of these consulting firms is equally tough. Still, some candidates will receive offers from more than one organization, so, if you had the choice of one of these firms, then which one should you choose?

Perhaps unsurprisingly, there is little difference in the Glassdoor ratings of each firm, and this most likely reflects the similarity in the work they do and the constant movement of employees between them.

All the firms are ranked in the top graduate employer lists consistently year on year and are deemed to be great places to work.

How Does the Salary Vary Between the Big Three and the Big Four Consulting Firms? 

The salary structure within the Big Three consulting firms (McKinsey, BCG, and Bain) and the Big Four consulting firms (Deloitte, PwC, EY and KPMG) can vary based on several factors, including location, level of seniority, performance, and the specific service line or practice area. Here are some general considerations regarding salary differences:
For entry level positions, the Big Three consulting firms tend to offer higher base salaries compared to the Big Four. This discrepancy can be attributed to the highly competitive nature of securing a position at McKinsey, BCG, and Bain and the specialized focus on strategy consulting, which often attracts top-tier talent.

At the Big Three, the base salary for an Undergraduate and Master’s Consultant in the US varies between 110,000 USD (BCG) and 112,000 USD (McKinsey, Bain). On top, a performance bonus of up to 30,000 USD (McKinsey) is possible and you may be supported with housing allowance, relocation services and retirement benefits. Moreover, the Big Three usually offer a signing bonus of roughly 5,000 USD. 

Looking across the Big Four firms, there are differences in salary between the four and also between the professional service practices. For example, the strategy consulting practice of PwC, Strategy&, pays roughly 50% more in starting salary than they do for audit graduates.

For entry-level positions, Deloitte pays the most with a base salary of about 88,000 USD to 95,000 USD. It is followed by PwC and EY with roughly 85,000 USD. KPMG has the broadest range for entry-level positions with base salaries ranging from 78,000 USD to 90,000 USD. Just as the Big Three, the Big Four also offer performance bonuses, but usually on a smaller scale. You can most likely expect to get up to 15,000 USD on top of your base salary but note that the regulations for these bonuses are quite different between the firms. A signing bonus is also quite common among the Big Four, so you can look forward to about 5,000 USD that sweeten the start into your career in consulting. 

Compensation packages also include benefits and perks, such as health insurance, retirement plans, vacation time, and professional development opportunities. While the general benefits packages offered by the Big Three and the Big Four are competitive, there may be variations in specific benefits based on firm policies and practices.

How Does the Work-Life-Balance Differ Between the Big Three and the Big Four Consulting Firms? 

The work environment in the Big Three firms is often described as fast-paced, intense, and very demanding. The nature of their strategic engagements and high-profile clients may lead to longer working hours and more extensive travel activities than you may encounter when working for the Big Four. 

The Big Four consulting firms, while still demanding, often provide a more balanced work environment due to their broader service lines and varied projects. However, the workload can still be demanding during peak periods as in the professional services world, it is very common to work 12+ hours days, 5 days a week. 

How Do Career Opportunities Differ between the Big Three and the Big Four Consulting Firms? 

A career in either the Big Three or the Big Four consulting firms is already an achievement, so if you have made it this far, you can already be very proud of yourself. Nevertheless, there are some differences between the groups, so let’s take a look at them: 

The Big Three consulting firms are the most prestigious firms in the consulting industry, so career opportunities could not be better. Many alumni of McKinsey, BCG, or Bain now work in industry leadership positions and executive roles, such as CEOs, CFOs, or other C-suite positions. Consultants often move into corporate strategy or business development roles of former clients and leverage their expertise in strategy formulation, market analysis, and organizational design. The analytical and strategic skills gained at one of the Big Three consulting firms also make alumni attractive candidates for private equity and venture capital firms and their entrepreneurial drive often results in the launch of their own startups, or ventures. 

The Big Four consulting firms are a little less prestigious than MBB, but still offer great career opportunities. Their alumni may not be as widely represented in C-suite positions as the colleagues from McKinsey, BCG, or Bain, are, but taking on a leadership role in an SMU or startup is still a very common career path for former consultants at the Big Four. Due to the global network of these firms, there are also opportunities for international projects, or secondments. 

The Big Four firms also offer diverse internal corporate roles, enabling professionals to contribute to the firm's operations, strategy, marketing, human resources, technology, and other functional areas. These roles support the overall functioning of the firms and provide opportunities for individuals who prefer working in internal-facing positions, which usually require less traveling and offer a better work-life-balance than client-facing roles.

Summing It Up 

Overall, both the Big Three and the Big Four consulting firms are major players in the professional services industry, with a global presence and a strong reputation. While the Big Three have a strong focus on strategic management consulting, the Big Four have their roots as accounting firms and offer a broader range of services, including audit, tax, and advisory. 

While the Big Three are generally considered more prestigious, both groups offer great career opportunities with interesting projects, exposure to top-level management and steep learning curves. 

A career in either of the Big 3 or Big 4 consulting firms is usually a great start into the business world, but expectations on applicants are high. The screening process for all the firms is rigorous and followed by a demanding interview process including several case interviews and personal fit assessments. 

If you want to secure an offer at either McKinsey, BCG, or Bain or Deloitte, PwC, EY, or KPMG, the key to success is always the same: Prepare! Make sure to gather information on the firm and the specifics of their application process, practice for your case interview and gather feedback on your performance from peers. At PrepLounge, we offer a variety of preparation materials. You can start by reading through our Case Interview Basics, then solve some cases from our Case Library and practice with peers on the Meeting Board. With limited time left, one of our coaching programs may also be an option for you. We wish you much success for your career in consulting!