GPT 5.0 Launch Sparks Fresh Concern for Finance Teams Battling AI-Driven Expense Fraud

Medius AI Expense Fraud survey highlights a growing challenge for finance professionals as GPT-5 emerges. As the world reacts to the launch of GPT-5.0, a new survey from spend management leader, Medius, reveals a mounting crisis for finance professionals already struggling to detect AI-generated expense fraud. With nearly a third (32%¹) of respondents admitting they wouldn’t recognize a fake expense report if it came across their desk, the arrival of a more powerful generative AI model threatens to only widen an already dangerous gap in business defences.

The survey, conducted among 1,000 finance professionals in the US and UK, found that three in ten respondents (30%) are already reporting a rise in faked receipts since the beginning of 2024 – following the launch of GPT 4.0 – there is a growing fear that advanced generative AI models, like GPT-5.0, could make fraudulent claims harder to detect and easier to produce.

This surge in AI-enhanced fraud is hitting an already overstretched profession. Forty-two percent of finance professionals surveyed have suspected a colleague of submitting a fake or altered receipt, while over one-third (34%) say they’ve been pressured to approve an expense that didn’t seem legitimate. And it’s not just theoretical – when asked to share the most questionable expense they’ve ever seen approved, respondents revealed claims including a diamond ring, a luxury car, fees for a Japanese school, and even expenses for a strip club.

Commenting on the results, Gary Hall, Chief Product Officer at Medius, said “We’re at a tipping point. GPT-5.0 promises even more realism, more precision and more ease for the user. That’s great for innovation, but it’s also a gift to fraudsters. When AI-generated documents are indistinguishable from the real thing, legacy finance systems simply can’t cope. This is no longer a niche IT issue – it’s a frontline finance challenge.”

Despite 92%² of finance professionals saying their company’s expense policies are clearly communicated, two thirds (66%) believe that most employees do not follow them closely – a number that jumps to 78% in industries like manufacturing and utilities. That disconnect is more than just a compliance issue – it reflects a deeper cultural and operational problem. When asked what was more frustrating, navigating their company’s expense policy or assembling IKEA furniture, 30% said the policy was worse.

At the same time, the expense management process remains deeply inefficient. Forty-five percent of respondents cite chasing receipts as a major pain point, followed by approval delays (44%) and manual data entry (40%). One in three (33%) say that detecting fraud is one of their most significant ongoing challenges. Making matters worse, 29%³ percent admit they have bent the rules themselves – rounding up figures or reclassifying personal costs as business expenses.

Hall added: “The stories we’re hearing make it clear that expense abuse isn’t just hypothetical. Combine that with AI-powered fakes, and businesses are heading straight into a compliance crisis. Finance teams need intelligent anomaly detection systems, not manual guesswork, to stay ahead of what’s coming.”

To learn more about how businesses can improve their expense processes, and to learn more about Medius’s new AI receipt detection technology within Expensya by Medius, please visit https://www.expensya.com/en/solutions/smart-policy/#ai-receipt-verification or  https://www.medius.com/solutions/expense/smart-policy/#ai-receipt-verification.