WPP Study Finds Radio’s Real Power Is ‘Priming’ Consumers Before They Shop.

Radio’s ability to shape consumer decisions depends less on reach alone and more on how well it’s integrated with other channels, according to a new global study from WPP Media and the University of Oxford’s Saïd Business School.

The report, titled “How Humans Decide,” analyzes more than 1.2 million individual purchase journeys across 200 product categories in 47 countries. Its central conclusion: most consumers are not making decisions in the moment. Instead, they act on brand preferences formed long before they start shopping.

The 84% Rule

The study finds 84% of purchases are made by consumers who already have a brand bias before they enter the active shopping stage. That leaves only 16% of purchases open to lower-funnel influence — the phase where marketers often invest the most heavily in paid advertising.

In that pre-decision “priming stage,” media channels such as radio and podcasts play a critical role in shaping awareness, trust, and emotional connection — the groundwork that determines which brands consumers will consider later on. WPP calls this long-term process “brand priming,” and it applies across every category studied, from consumer electronics to fast food to financial services.

“Buyers do not come to a brand fresh in the lower funnel,” the report says. “They will likely already know which brand they want to buy.”

The result, the report says, is that much of performance marketing’s role is converting buyers rather than acquiring new ones. “Brand-building communication is therefore not optional — it is the essential groundwork that determines whether a brand is even in contention when a purchase decision arises.,” WPP concludes.

Receptivity And Touchpoint Power

The research also examines why some marketing works better than others, introducing two concepts often overlooked in traditional planning — receptivity and touchpoint influence.

Receptivity measures how open consumers are to being influenced by marketing. Touchpoint influence refers to how much a particular form of contact changes behavior.

WPP’s data shows paid channels are indispensable for creating brand familiarity and emotional bias during the priming phase. But conversion from bias to purchase typically comes from a broader mix of touchpoints. In the active purchase stage, owned, shared, and earned channels — such as word-of-mouth recommendations, online reviews, and email — are nearly three times more powerful than paid media alone in converting consumers who are already primed.

That means a consumer who hears a radio campaign may be predisposed to buy, but the final nudge often comes through reinforcing channels that validate that choice.

From Reach To Influence

The study challenges what it calls marketing’s “golden rules” — prioritizing reach and attention — arguing that these measures overlook differences among categories, audiences and media environments. Instead, WPP recommends shifting from reach-based media planning to influence-based planning, balancing paid channels like radio alongside owned, shared, and earned media.

In that model, radio serves as an influence-builder, not just a reach vehicle. Its strength lies in emotional storytelling and consistency, but advertisers are urged to connect broadcast and streaming campaigns with brand-owned assets to multiply impact.

Implications For Audio Marketers

The findings reinforce the trend toward moving audio campaigns beyond the 30-second spot. Broadcasters and their clients increasingly integrate on-air storytelling, branded podcasts, live events, email, and social media into unified campaigns that influence consumers across the full purchase journey.

The WPP/Oxford research provides empirical support for that approach, showing that choosing the “best four” touchpoints for a campaign nearly doubles the chance of influencing a purchase — 47% versus 20% — compared with random selection. That makes radio’s strategic placement and integration crucial. Rather than an isolated awareness driver, it functions best as a bridge between paid exposure and the reinforcing owned and earned experiences that confirm a listener’s decision to buy.