Big Four giant EY is all in on AI — and it’s paying off

• Big Four firm EY has made AI a key cornerstone of its business.
• Annual results for the 2025 financial year, released on Thursday, suggest the strategy is paying off.
• Overall revenue was up 4%, while AI-related consulting revenues climbed 30%.

AI is disrupting the world of consulting, and so far, EY is cashing in.

The Big Four consulting and accounting firm reported on Wednesday that AI-related revenue was up 30% in its 2025 financial year, which covers the year ending June 30.

EY said that consulting services like "delivering enterprise-wide transformations" and "AI governance frameworks that help drive the responsible implementation of AI" helped drive the surge in demand.

The firm said it invests more than $1 billion each year in developing AI-first platforms and products, including 1,000 AI agents and the deployment of more than 100 internal AI applications.

Overall global revenue rose 4% in the 2025 financial year to hit $53.2 billion.

EY's rate of growth was in line with that of the 2024 financial year, but remained much lower than the 14.2% jump in revenue reported in 2023.

The firm's assurance division generated the most revenue, bringing in $17.8 billion, but its tax line was the strongest-performing, rising 5.5% to generate $12.7 billion.

Consulting showed strong signs of recovery from the previous year, when it only rose by 0.1%. In its 2025 financial year, consulting was up 5.2% to generate $16.4 billion for EY.

EY-Parthenon, which provides strategy and transactions services, shrank by 0.4%, with revenue of $6.2 billion. Global dealmaking activity was slow throughout 2024 and 2025, but the market has started to pick up in recent months.

In March, EY announced that it was expanding the EY-Parthenon brand, merging its strategy, transactions, and deal advisory work under the division. The merger brought 16,000 new EY professionals into the EY-Parthenon division.

Janet Truncale, EY's CEO and global chair, launched a major new strategy called "All In" soon after she took over leadership of the firm in July 2024. The changes have altered EY's core business lines and global structure.

"Now in its second year, the EY All in strategy reinforces a commitment to AI-powered solutions, deeper industry alliances and continuous learning and development for EY people," Truncale said in Wednesday's earnings report.

EY is the second of the Big Four firms after Deloitte to report global earnings for the 2025 financial year. PwC and KPMG are yet to share results.

Following a pandemic-era boom, the four firms have seen demand for their consulting services wane. Overstaffed departments and tight economies saw annual revenue growth fall across the board. The firms are also facing existential questions about how AI will alter their long-held business models and staffing structures.

But signs point to a slow uptick in business. Earlier this month, Deloitte reported a 5% rise in global revenue in its 2025 financial year, which ends 31 May 2025.

That was up from Deloitte's 3.1% growth the previous year, though, like EY, the firm's growth is still short of the double-digit growth of the pandemic years.

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