THE The big four professional services firms are grappling with AI on two fronts: they must both implement the new technology internally and help their customers do the same.
They are customer zero when it comes to how businesses and employees adapt to the future of AI.
I’ve covered the consulting industry for Business Insider all year, including interview leaders, landing scoopsand visit consulting giants campus and headquarters. Here are my four key takeaways on how the Big Four approached AI in 2025.
1. The year of the AI agent
The Big Four have invested heavily in automation and AI for years, but 2025 was the year these the tools have become widespread.
Employees in the audit, tax, and consulting industries now regularly use chatbots and agentic AI systems, and clients also have increasing access to them.
Deloitte has deployed Zora AI, an agent platform built with Nvidia, which offers its clients “intelligent digital workers” capable of completing tasks autonomously. The company also expanded the generative AI capabilities of Omnia, its cloud-based auditing and assurance platform, and entered into an agreement with Anthropic in October to deploy Claude AI to its 470,000 employees worldwide.
EY has launched its own agent platform, EY.aigiving 80,000 tax agents access to 150 AI agents for tasks such as data collection, document review and tax compliance. EY told Business Insider that it had 1,000 advanced AI agents in development or production in 2025, with plans to reach 100,000 by 2028, and is investing more than $1 billion annually in AI platforms and products.
PwC introduced its agent platform, Agent OS, in March and has since deployed 25,000 intelligent agents across client operations. A PwC spokesperson told Business Insider that partnerships with companies like Salesforce, CrewAI and AWS were key to how PWC drove AI-driven growth in 2025.
KPMG followed in June with KPMG Workbench, an agentic AI platform developed with Microsoft that connects 50 AI agents and chatbots, with nearly 1,000 more in development. In October, it launched KPMG Velocity for advisory work, adding to Clara, its audit platform used by more than 95,000 auditors worldwide, and the digital gateway for tax.
The tools are not infallible. In October, Deloitte agreed to partially refund the Australian government after errors were discovered in a report created in part using AI.
2. A slowdown in entry hiring
Across all industries, the big question is what AI will do for human jobs. In consulting, technology is already accelerating the shift in focus from workforce to value.
In August, Business Insider obtained part of an internal presentation showing that PwC US planned to reduce the hiring of graduates by a third over the next three years. A bullet point on the presentation slide noted that management’s decision to slow associate-level recruiting was related in part to the “impact of AI.”
The company said the cuts reflected “the rapid pace of technological change that is reshaping the way we work” and a “historically low” attrition rate.
AI disruptions are also impacting the upper tiers of the Big Four. Associates, who constitute the highest rank within companies, are increasingly leaving the Big Four for mid-sized organizations and startups. Several executives interviewed by Business Insider cited a faster pace, better promotion opportunities, and the chance to participate in the next wave of AI innovation as reasons to leave.
PwC plans to cut U.S. graduate recruiting by a third over the next three years, Business Insider reported in August. Jack Taylor/Getty Images
3. The rise of the technologist
There is a talent group the Big Four are in the market for: technologists. EY has added 61,000 technologists to its ranks since 2023, according to its latest annual report. They now represent around 15% of its total workforce.
PwC is “looking for hundreds and hundreds of engineers“, Mohamed Kande, the company’s global president, told the BBC in November. The company created an engineering career path to “elevate engineering excellence” across the company and expand opportunities for technical talent, PwC told Business Insider.
Upskilling has also become a top priority for the Big Four.
In January, EY rolled out an AI tool for its employees that helps them identify how their work will change… thanks to AI. The goal is to help them determine how they can better use technology in their current job and adapt for the future.
Nearly 100,000 EY employees, or about a quarter of the workforce, have also earned a digital “AI badge” for completing one of the firm’s new AI training programs.
But as Business Insider learned then attend KPMG AI training For professional services tax interns, some of the most effective uses of AI rely on strong incentives.
KPMG tax interns complete AI training at the firm’s training center in Lakehouse, Florida. Polly Thompson
4. Work evolves
The work of consultants and accountants is evolving. Outright consulting projects are being replaced by long-term partnerships in which consultants build, implement and maintain tools for businesses.
By 2025, organizations will integrate AI into their existing workflows, Matt Wood, PwC’s global and US director of technology and innovation, told Business Insider. But in 2026, the work PwC will do will be “helping clients turn that model on its head” and designing processes with AI in mind from the start, Wood said.
Raj Sharma, EY Global Managing Partner for Growth and Innovation, told Business Insider in January that the power of AI agents is forcing his company to reconsider its business model. Instead of charging clients based on the hours and resources EY could devote to a project, Sharma said AI agents could advocate a “service as software” approach in which clients pay based on the outcome.
The evolution of services means that the day-to-day work of consultants is also evolving, with the work of juniors expected to be disrupted first.
At PwC, new hires will fill the roles that managers do within three years, as they oversee AI performing routine, repetitive audit tasks, Jenn Kosar, Head of AI Assurance at PwCtold Business Insider in August.
KPMG also prepares its junior consultants for career acceleration.
“We want juniors to become agent managers,” Niale Cleobury, global head of AI workforce at KPMG, told Business Insider in an interview in November. They will manage teams of AI Agents and play a greater role in strategic decisions, he said.
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