Podcast’s Share Of Listening Grows, But Nielsen Says Marketers Undervaluing ROI.

Podcast listening now accounts for a growing share of Americans’ ad-supported audio time, reinforcing its position as a core component of the media mix, according to Nielsen’s latest “Audio Today” report.

The report shows podcasts represented 21% of ad-supported audio listening during the fourth quarter among adults 18 and older. The data — from Edison Research’s Share of Ear — shows podcasts rank second only to AM/FM radio, whose 61% share remains the clear leader.

“The reality is that radio is the undisputed leader in ad-supported audio time,” the report says. But Nielsen positions the two platforms as complementary rather than competitive. Radio provides immediate scale and frequency, while podcasts offer more targeted engagement and incremental reach — especially among younger, more digitally oriented audiences.

“For advertisers planning audio marketing campaigns, it is critical to understand that more than 80% of all daily ad-supported audio time goes to radio and podcasts, while only 15% goes to streaming music,” the report says. 

Nielsen says podcast listening varies significantly by demographic group. Podcasts account for 32% of ad-supported audio listening among adults 18-34, compared to 20% among adults 35-49 and 12% among adults 50 and older, based on Edison data.

That generational divide is reshaping how advertisers approach audio planning. While broadcast radio still delivers the largest share of ad-supported listening, Nielsen says podcasts help expand how advertisers reach audiences across different listening contexts and devices.

Nielsen reports radio reaches 92% of U.S. adults each week, maintaining its position as the dominant mass-reach medium in audio. By comparison, podcasts reach a smaller — but still significant — portion of the population, offering advertisers a way to extend campaigns. For instance, among 18- to 34-year-olds AM/FM reaches 89% of consumers. But when podcasts are layered into a marketing campaign, it adds another five points of incremental reach. 

“When you layer in the rising power of podcasts, you aren’t just adding a line item — you’re building a comprehensive audio strategy that achieves nearly 100% coverage,” the report says. Nielsen says that underscores how audio’s strength lies not just in individual platforms, but in how those platforms work together to maximize reach across increasingly fragmented listening behaviors.

Marketers’ growing reliance on digital media may also lead to misallocated ad dollars, as podcasts and radio continue to deliver stronger returns than their perceived value. The report says that advertisers are increasing investment in digital channels because they are seen as more measurable and easier to attribute.

But Nielsen cautions that “ease of measurement does not always equate to effectiveness or higher ROI.” It blames a reliance on attribution and platform-reported metrics, which can skew decision-making. “Proprietary KPIs and lower CPMs can be misleading,” the report says, noting that a channel’s ability to claim conversion credit does not necessarily reflect its true contribution to outcomes.

As a result, Nielsen says traditional channels like radio are often underutilized. Despite being ranked lowest by marketers in perceived effectiveness, radio delivers some of the strongest returns. Using its Global Compass data, Nielsen finds radio generates among the highest ROI globally, second only to social media.

Podcasts show a similar disconnect. The report says they deliver ROI comparable to TV and digital display yet remain underused relative to their performance.

The findings point to what Nielsen describes as a broader misalignment between perception and reality. That gap, the report suggests, is leading marketers to underinvest in channels that can deliver meaningful business results. For advertisers, the implication is that optimizing media plans requires looking beyond easily measured metrics and reassessing the role of channels like podcasts based on actual performance, not perception.

Download the report HERE.