
A new analysis of more than $400 million in audio spend spanning 30 years is underscoring how radio and podcast advertising contribute an average of 18% to branded search activity, with some brands experiencing contributions exceeding 40%.
The study, tabulated by audio ad agency Oxford Road, highlights audio’s dual role in generating immediate responses and fostering long-term engagement. This marks radio and other audio platforms as key elements of a full-funnel marketing strategy, addressing gaps in attribution and challenging short-term performance biases.
Audio advertising delivers measurable impacts on branded search within the first week of exposure. In eight out of ten brands analyzed, week-of correlations between audio spend and branded search activity reached a 97% confidence level. The study also revealed that delayed effects – where audio exposure drives search activity weeks after initial spending—are significant, particularly for business-to-business brands with longer consideration cycles.
Business-to-consumer brands, by contrast, showed more immediate but shorter-lived effects.
The report emphasized the value of consistent audio investment, with brands maintaining steady campaigns seeing stronger long-term results compared to those with sporadic spending. However, Oxford Road’s analysis identified diminishing returns with increased audio spending. While initial investment leads to substantial search growth, incremental spending beyond an optimal range yields smaller gains.
Audio campaigns accounted for 18% of branded search volume on average across all clients. This percentage was higher for brands with sustained and high-intensity audio investments. The findings affirm that audio is more than a supporting channel—it is a major driver of discoverability and consumer action.
Oxford Road EVP of Strategy Giles Martin remarked, “Our findings give evidence for what we’ve always believed – that audio marketing not only inspires action in its listeners but that it requires an investment mindset to reap the full benefits.”
He added, “Marketers should not underestimate the role of audio in driving both short-term performance and ‘mental availability.’ Improved awareness, recall, consideration, intent, and credibility are the types of measures that underpin this boost in search activity. Leading brands strategically leverage audio smartly across the full funnel by delivering short-term high-intent traffic, efficient customer acquisition, expanded reach and awareness, and priming future demand that can deliver returns for quarters and years to come.”
The full survey findings can be found through Oxford Road.