Consulting had a year of huge change in 2025. Here's how the Big Four firms performed this year.

Deloitte recorded 4.8% annual revenue growth in its most recent financial year.

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• The Big Four — EY, Deloitte, KPMG, and PwC — are the world's largest accounting and consulting firms.
• The firms pull in billions annually, but are at a transformative moment as AI reshapes the industry.
• This is how the Big Four said they performed in their most recent financial years.

Deloitte, EY, KPMG, and PwC make up the world's largest professional services firms — known as the Big Four.