The Top Ten Accounting Firms, Ranked

New York, NY · Est. 1845 · Largest Big Four firm; ~$67B global revenue

• ·Largest professional-services firm in the world by verified revenue and headcount. [Deloitte global revenue report]
• ·Audits the largest share of Fortune 500 companies of any firm. [Audit Analytics]

New York, NY · Est. 1849 · ~$55B global revenue

• ·Audits the most S&P 500 companies by market capitalization. [Audit Analytics]
• ·Consistently top-ranked in accounting-firm prestige surveys. [Vault Accounting 50]

New York, NY · Est. 1849 · ~$51B global revenue

• ·Leading audit share among technology IPOs, verified by listing data. [Audit Analytics / IPO records]
• ·Strongest recent PCAOB inspection trend among Big Four peers. [PCAOB inspection reports]

New York, NY · Est. 1897 · ~$38B global revenue

• ·Deep verified strength in financial-services audit and advisory. [Audit Analytics]
• ·Consistent top-four global scale with full public reporting. [KPMG global review]

Chicago, IL · Est. 1910 · Largest non-Big-Four US firm; ~$2.9B revenue

• ·Largest US accounting firm outside the Big Four by verified revenue. [Inside Public Accounting Top 500]
• ·First major US firm to adopt an ESOP ownership structure, improving independence incentives. [BDO announcements / trade press]

Chicago, IL · Est. 1926 · ~$4B revenue; middle-market leader

• ·Recognized leader in middle-market audit and tax, verified by client-base data. [IPA Top 500 / RSM disclosures]
• ·First-mover in transatlantic middle-market integration with RSM UK. [Firm announcements]

Chicago, IL · Est. 1924 · ~$3B US revenue

• ·Strong middle-market public-company audit share. [Audit Analytics]
• ·Century-long continuous US operating record. [Firm history]

Springfield, MO / New York · Est. 2023 · Formed by BKD + DHG merger; global Mazars network

• ·Created the largest new US firm in decades through a verified two-firm merger. [IPA reporting]
• ·Global network access via Mazars strengthens cross-border capability. [Firm disclosures]

New York, NY · Est. 1942 · ~$1.3B US revenue

• ·Verified specialty depth in healthcare, banking, and not-for-profit audit. [IPA Top 500 profiles]
• ·Consistent top-ten US revenue placement. [Inside Public Accounting]

Chicago, IL · Est. 1931 · ~$1.5B revenue; Moss Adams merger pending

• ·Announced combination with Moss Adams creates a top-six US firm by revenue. [Firm announcements / IPA]
• ·Strong public-sector and advisory practice record. [IPA Top 500]