AI has overtaken social media as a trusted shopping adviser and a personal ‘phone-a-friend’ in arguments for more than a third of global consumers, according to research from performance marketing company RTB House.
The company’s latest global consumer study, “Who’s Buying? Consumer Trust in the Age of Agentic AI,” surveyed shoppers across the United States as well as consumers from the United Kingdom, France and Japan, highlighting a profound shift in brand discovery. Rather than compressing the path to purchase, AI is acting as a consideration engine, introducing unfamiliar brands and expanding the research phase.
Leading AI tools now beat TikTok, Instagram and Facebook for trustworthiness among US and international shoppers. They also outperform newspapers and major media outlets. However, trust isn’t evenly spread across AI platforms, as Google AI Overviews and ChatGPT hold a lead while Claude and Grok lag behind both in the US and globally.
42% of US consumers and 33% of non-US consumers say AI tools increase the time it takes them to reach a final purchase decision by surfacing more brands, products and alternatives to consider. With US shoppers typically visiting a website 4 to 6 times before completing a purchase, AI is stretching this consideration window even further.
The effect is strongest among US Gen Z (48%), but holds across every generation measured. The same pattern shows up in brand discovery: 59% of US consumers and 52% of non-US consumers say AI is good at surfacing brands they didn’t previously know, with US Gen X (61%) and Baby Boomers (62%) among the most receptive groups.
The trust in AI is culminating in financial delegation, with 42% of US Millennials saying they are comfortable giving an AI agent a budget of up to $250 to make a purchase on their behalf when a seven-day return window is guaranteed, compared to 27% of non-US Millennials.
However, human oversight remains paramount, with approval before checkout the single most requested safeguard globally.
“For more than a decade, e-commerce growth was driven by buying attention on social feeds and optimising for instant checkouts,” says Jaysen Gillespie, VP of Product Marketing & Analytics at RTB House. “This research proves that era is coming to an end. Consumers are turning to AI as an analytical powerhouse, using it to evaluate and discover brands, conduct price comparisons, and conduct deeper research before they buy. As AI expands the consideration window, competition is fiercer than ever.
“Modern marketers will find that while discovery happens in AI engines, the rubber meets the road at on-site and in-app monetisation. The longer research window gives marketers an opportunity to more deeply engage with timely and relevant offers across the entire shopper set. Our advice would be to take advantage of that extended window.”
*The research, “Who’s Buying? Consumer Trust in the Age of Agentic AI”, was conducted in June and July 2026 in partnership with Cint, surveying 1,840 respondents across the United States and a combined non-US group spanning the United Kingdom, France and Japan.
