Types of Consulting Firms: MBB, Tier 2, Big 4, Boutique

Consulting firms cluster into seven recognized types in 2026: MBB (the Big 3), Tier 2 strategy, Big 4, technology/IT, boutique and specialty, economic consulting, and HR/communications. Each type targets different clients, runs a different interview, and feeds different exit paths. Picking the right type is the first real decision in consulting recruiting.

TL;DR — What you need to know

• MBB: McKinsey, BCG, Bain. Under 1% acceptance, $110K-$125K undergrad pay, exclusive C-suite strategy.
• Tier 2: Oliver Wyman, Kearney, L.E.K., Strategy&, EY-Parthenon. 2-5% acceptance, $95K-$115K pay.
• Big 4: Deloitte, EY, PwC, KPMG. 5-15% acceptance, $75K-$95K, implementation-heavy.
• Tech consulting: Accenture, Capgemini, IBM Consulting, ZS Associates. Long engagements, product/CTO exits.
• Boutiques: Mars & Co, Simon-Kucher, A&M, FTI. Narrow niche depth, exits feed specialist leadership.

What are the main types of consulting firms?

The 2026 industry breaks into seven categories: MBB, Tier 2 strategy, Big 4, tech/IT, boutique/specialty, economic consulting, and HR/comms specialists. The same client (say, a Fortune 500 CFO) might hire different types for different jobs in the same year. The categories overlap in messy ways, but they still predict interview style, compensation band, and exit opportunities reliably.

Based on 5,000+ case interview sessions on Road to Offer, candidates preparing for MBB cases over-prepare quant and under-prepare structuring; candidates preparing for boutiques do the opposite. Knowing the firm type tells you which half of your prep matters more.

What are the Big 3 (MBB) consulting firms?

MBB refers to McKinsey, BCG, and Bain. Together they generate roughly $35B in revenue and employ about 85,000 consultants worldwide (Wikipedia Big Three; Management Consulted 2026).

McKinsey & Company

Largest by revenue (~$16B) and office count (130+). Strong in financial services, public sector, and pharma. See our McKinsey case interview guide.

Boston Consulting Group (BCG)

Second by revenue (~$13.5B) and growing fastest. Thought-leadership brand (BCG Matrix, Experience Curve). Strong in industrial goods, TMT, and energy. See our BCG case interview guide.

Bain & Company

Smallest and most selective by headcount. Dominant in private-equity due diligence with ~30% of revenue from PE clients. See our Bain case interview guide. For the full overview, see what is MBB consulting.

What are Tier 2 strategy firms?

Tier 2 is the strategy peloton: firms that compete directly with MBB on many mandates but sit a rung below in brand recognition. Acceptance rates run 2-5%, and the project-level work is often indistinguishable from MBB.

• Oliver Wyman: financial-services powerhouse, also strong in healthcare.
• Kearney: strategy plus deep operations and procurement.
• L.E.K. Consulting: strongest in healthcare, life sciences, and PE diligence.
• Roland Berger: Europe's largest strategy consultancy.
• Strategy& (PwC): ~3,800 consultants, ~$1.3B revenue, formed from PwC's 2014 Booz & Company acquisition.
• EY-Parthenon: EY's strategy arm, often cited closest to MBB.
• Monitor Deloitte: Deloitte's strategy arm from the 2013 Monitor Group acquisition.

"Tier 2 firms reward industry specialization in recruiting. A pharma background gets a real edge at L.E.K., a finance background at Oliver Wyman." Hacking the Case Interview 2026 Tier 2 report.

Free resource: practice MBB and Tier 2 cases

Run a free case on Road to Offer with AI scoring on structure, math, and synthesis, calibrated to MBB and Tier 2 standards. Try a free case →

What do Big 4 consulting firms do?

The Big 4 (Deloitte, PwC, EY, KPMG) started as audit firms and scaled into consulting over three decades. Combined they employ 1.5M+ globally, with consulting roughly a third of that. Practices span strategy, implementation, technology, risk, tax advisory, and human capital.

• Deloitte: largest Big 4 consulting practice. Monitor Deloitte handles strategy; Deloitte S&O handles broad advisory.
• PwC: Strategy& is the strategy arm; PwC Consulting handles tech and advisory.
• EY: EY-Parthenon (strategy) plus EY Consulting (advisory, tech).
• KPMG: KPMG Global Strategy Group (strategy) plus broad KPMG Advisory.

The practical takeaway: "Big 4 consulting" is not a single career. Joining Monitor Deloitte is closer to BCG than to Deloitte's broad advisory practice. For the head-to-head comparison, see Big 4 vs MBB consulting and Big 4 consulting firms overview.

What is tech and IT consulting?

Tech consulting firms focus on designing, building, and implementing technology: enterprise systems, cloud migrations, AI platforms, data infrastructure. They hire technologists as often as business generalists, and engagements typically run 6-24 months.

• Accenture: largest tech consultancy by headcount (700K+). Accenture Strategy is a distinct smaller strategy arm.
• Capgemini / Capgemini Invent: strong in Europe and engineering services.
• IBM Consulting: technology-first with a growing strategy practice.
• ZS Associates: tech-enabled commercial consulting, dominant in life sciences.
• Slalom and West Monroe: mid-market tech and digital firms.

Entry pay matches Big 4 broad consulting. Exits skew toward product management, corporate IT leadership, and tech startups rather than finance or private equity.

What are boutique and specialty consulting firms?

Boutiques pick a single function (pricing, innovation, restructuring) or single industry (life sciences, energy, PE) and go deep. A Simon-Kucher pricing consultant runs 30+ pricing projects in 2 years versus maybe 3 at MBB.

• Simon-Kucher: global pricing specialist.
• Alvarez & Marsal: restructuring and turnaround.
• Innosight: innovation and growth boutique founded by Clayton Christensen.
• OC&C Strategy Consultants: consumer and retail strategy boutique.
• Mars & Co: ultra-selective pure strategy boutique.
• FTI Consulting: financial advisory, restructuring, and litigation.

What is economic consulting?

Economic consulting firms sit at the intersection of consulting, finance, and law. They support antitrust cases, M&A regulatory review, litigation, and complex valuation. Clients are typically law firms and regulators rather than corporate executives.

• Analysis Group: largest private economic consultancy.
• Cornerstone Research: litigation and antitrust.
• NERA: 500+ economists across 23 offices.
• Charles River Associates: ~800 consultants, strong in antitrust and finance.
• Compass Lexecon: economic analysis for regulators and courts.

Economic interviews lean more on applied microeconomics, econometrics, and regression reasoning than classic strategy case structure.

How do the seven types compare across pay, work, and exits?

For a deeper firm-by-firm read, see management consulting firms ranking and consulting career path. For exact base, bonus, and signing comp by firm and tier, see the 2026 Consulting Salary Report.

How do you choose the right type of consulting firm?

Three filters cover most decisions.

What kind of work do you want?

Pure strategy lives at MBB and Tier 2. Implementation and tech delivery live at Big 4 and tech firms. Litigation and antitrust live at economic consulting. Pricing, restructuring, and innovation live at boutiques.

What is your target exit?

PE exits concentrate at MBB (especially Bain) and a few Tier 2 firms. Operations and tech leadership exits dominate Big 4 and tech consulting. Specialist leadership and academia come out of boutiques and economic consulting.

What is your background?

Generalists do best at MBB, Tier 2, and Big 4. Engineers fit cleanly into tech consulting. Economists and law-adjacent candidates fit economic consulting.

Each firm type runs its own recruiting calendar; the recruiting deadlines calendar tracks the dates by firm so you don't miss a window. Once your target is picked, the complete consulting toolkit covers cases, math drills, and PEI prep from there.

Frequently Asked Questions

What are the Big 3 consulting firms? McKinsey, BCG, and Bain (MBB). The three highest-prestige strategy firms globally, with 1-3% acceptance rates.

What is a Tier 2 consulting firm? A pure or near-pure strategy firm one rung below MBB, including Oliver Wyman, Kearney, L.E.K., Strategy&, EY-Parthenon, and Monitor Deloitte.

Are the Big 4 considered consulting firms? Partly. Audit-origin firms (Deloitte, EY, PwC, KPMG) with substantial consulting arms plus dedicated strategy arms.

What is the difference between strategy and IT consulting? Strategy firms run short C-suite engagements about what to do; IT firms run 6-24 month engagements about how to build and ship technology.

Which type is best for career growth? MBB produces the widest exit funnel. Industry-focused candidates may prefer Tier 2 or a boutique for faster specialization.

Are boutiques harder to get into than MBB? Usually no, but pure-play strategy boutiques like Mars & Co can rival MBB on individual acceptance rates due to tiny class sizes.

Sources (checked April 28, 2026)

• Hacking the Case Interview Tier 2 firms 2026: hackingthecaseinterview.com/pages/tier-2-consulting-firms
• Leland Tier 2 firms 2026: joinleland.com
• Statista management consulting global revenue: statista.com
• Wikipedia Big Three management consultancies: en.wikipedia.org/wiki/Big_Three_(management_consultancies)
• Consultancy.uk consulting industry pyramid 2026: consultancy.uk
• Wall Street Oasis 2026 strategy firm tier list: wallstreetoasis.com