iO predicts organic search traffic to plummet 50% by 2028 as AI transforms customer behaviour

Generative AI will dramatically reshape how customers find information — businesses must act now to stay relevant.

September 25, 2025

As a leading digital agency in Europe, iO has examined recent developments surrounding Large Language Models (LLMs). The way customers make buying decisions is changing again. Fifteen years ago, search engines transformed how companies thought about visibility and relevance online. Today, the rise of LLMs is reshaping the customer journey at an unprecedented pace.

iO predicts that many brands will see their organic search traffic decline by 50% or more by 2028 as customers increasingly embrace generative AI-powered search. This assessment aligns with Gartner's estimates that by 2028, many brands will see their site traffic from organic search decrease by 50% or more as customers embrace generative AI-powered search.

By 2028, traditional search traffic will face a dramatic decline

The digital world is once again at a turning point. The growth of LLMs mirrors the rise of traditional search engines fifteen years ago. Companies that moved early to optimise their visibility with SEO (Search Engine Optimisation) gained a decisive advantage.

The same urgency applies today for AI-driven search. As both iO and Gartner predict a potential 50% or greater decrease in organic search traffic by 2028, LLMs and generative AI search engines are rapidly becoming the primary way to find information, advice, and recommendations. Just as SEO became essential for traditional search engines, GEO (Generative Engine Optimisation) is emerging as the way to optimise visibility for these AI-driven search experiences. Businesses that delay implementing GEO risk falling behind whilst competitors secure the visibility and trust of their customers.

Both B2C and B2B brands are jumping on the bandwagon massively

iO is already helping businesses take action. In recent months, the agency has launched more than 30 dedicated LLM tracks for clients, including Wolters Kluwer, Suzuki, TotalEnergies Power & Gas, Optiphar, Partena Professional, Facilicom, and Zilveren Kruis. These companies have recognised the urgency of optimising their visibility in LLMs and are moving fast to protect and grow their competitive position.

“Forward-thinking organisations understand that visibility in LLMs is no longer optional — it is mission-critical,” said Pieter Janssens, CEO of iO. “Just as with the rise of search engines, the companies that take action today will define the standards of tomorrow. This is not a ‘wait and see’ moment; it is the time to seize opportunities and secure relevance in a transformed market.”

Just like with Google, it's still a major black box

Just like with search engines, influencing LLMs is also not easy. Many brands and agencies struggle with getting the right technology to measure and impact that findability. iO recently launched its own iO Bonzai, an AI orchestration layer that can query 12 LLMs simultaneously, keep client data secure, and measure what visibility impact they create for their clients.

Source: AI in Marketing: How to Prepare for the Future of Search. (Gartner)

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