$1.4B: More content, larger audience, increased ad spending, and DAI fuel record podcast revenue growth (IAB)

This morning sees the release of the U.S. Podcast Advertising Revenue Study published by the Interactive Advertising Bureau (IAB), with field work by PwC. It is the leading annual report measuring the money of podcasting, keenly awaited by the entire podcast trade. Today’s report details 2021, and projects growth in the 2022-2024 time frame.


“U.S. podcast advertising revenues surpassed the $1 billion mark in 2021 for the first time (to $1.4B), as it continues to be one of the fastest growing channels in digital media. With 72% growth, podcast advertising grew twice as fast as the total internet advertising market.” –U.S. Podcast Advertising Revenue Study, IAB

Growth, Past and Future

The report calls 2021 podcast growth “explosive,” and pegs it at 72% — about twice the rate of growth in the total internet advertising market (+35%). The chart below illustrates the IAB’s 2015-2021 podcast revenue growth assessment:

The key growth drivers, as described in the report:

  • A continually expanding user base consuming a growing library of engaging and diverse content
  • Advertisers increasing their use of seamless, automated digital ad delivery functionality—particularly dynamic ad insertion
  • Increased ad spend by existing and new advertisers across multiple ad industry categories

And the future? The IAB projects through 2024, and it is vigorous growth all the way:

Keys to Continued Growth

How to keep the momentum going? The IAB keynotes continued adoption of technical tools well established in the wider internet advertising ecosystem:

  • Use of brand safety and suitability tools
  • Advanced audience targeting
  • Ad effectiveness solutions

We’ve been watching the growing adoption in dynamic ad insertion (DAI), and note with interest that in 2021 that particular technology represented 84% of podcast ad revenue. DAI is the technology by which podcast ads are placed in real time into episodes across a show’s entire portfolio. The illustration below clarifies the fairly quick overthrow of baked-in ads (part of a single episode’s audio file) by DAI:

DAI ads can be host-read (the voice of the podcast) or announcer read (an unaffiliated pro voice). The share of announcer-read ads grew from 35% to 40% in 2021 — unfavorable news to advocates of the host-listener trust relationship.

Change of Leadership

Podcast has been well reputed as a key marketing venue for direct to consumer (DTC) retail companies — think mattresses. In 2021 that category dropped to 11% share of ad spend, from 19% in 2020. Newly at the top of the category list for 2021 is financial services.

When it comes to leading podcast categories for revenue generation, the News category leads the way with 19% of the dollars. The Comedy category (which includes mostly serious and very popular interview shows hosted by comedians), owned 13% of ad revenue in 2021. Both those categories dropped significantly from their 2020 shares.

One category which gained substantial revenue share in 2021 was Sports, leaping from 5% to 11%.

What of Programmatic?

“About 2% of total revenues,” the IAB says. “Podcasting continues to lag far behind the rest of the digital ad ecosystem in leveraging programmatic advertising.


Brad Hill