Digital Ad Prices Slide As Streaming Inventory Surges.

The streaming ad boom is creating more places for marketers to spend their money, but all that new inventory is putting pressure on what sellers can charge. New data from Guideline shows U.S. digital ad prices continuing to fall as streaming platforms pump more advertising opportunities into the marketplace — a trend that has implications for broadcasters that increasingly sell digital inventory alongside their traditional radio spots.

Guideline Chief Insights and Analytics Officer Sean Wright says that the average U.S. digital CPM fell to $9.06 during the second quarter, continuing a decline from roughly $10 a couple of years ago. Rather than a sudden correction, he says prices have been moving steadily lower, losing roughly 25 cents per quarter.

The primary culprit is basic supply and demand. Streaming services have opened significantly more programming to advertising, giving buyers an expanding pool of impressions without an equivalent increase in advertiser demand.

“Demand is about as what it was last year, but supply is exponentially larger,” Wright says. “And so naturally, in order to move it, prices have to come down.”

Video advertising illustrates the trend. Guideline says U.S. video CPMs have fallen 7% year over year and are now hovering around $11 across platforms. On Guideline’s latest podcast, Wright specifically points to the addition of advertising on services such as Amazon as one factor increasing the amount of inventory available to buyers.

That presents a complicated picture for radio. Streaming video is competing for many of the same advertising dollars broadcasters pursue, but the proliferation of inventory is also making that marketplace increasingly price competitive. And broadcasters themselves have a stake in the trend as radio groups expand their digital businesses and sell streaming audio, video, display and other digital inventory alongside over-the-air advertising.

More Pricing Pressure

The downward movement is not confined to a single platform. Wright says video-platform pricing peaked around the middle of 2025 and has since fallen by about $1 on a CPM basis.

“There’s a lot of video inventory globally, and so it’s a lot harder to kind of argue for pricing,” he says.

Social media is behaving differently. Guideline says social CPMs remain around $4 and have been relatively consistent for the past several years. Wright says TikTok’s combination of scale and low CPMs has helped keep a lid on what competing social platforms can charge.

Digital’s programmatic pricing in Guideline’s data has also remained relatively steady, generally between $10.50 and $10.80. But Wright cautions that the company’s dataset is weighted toward premium transactions such as private marketplaces and programmatic guaranteed buys rather than inexpensive open-market display inventory.

The broader pricing averages also mask significant changes in what different categories of advertisers are buying. Guideline says pharmaceutical advertisers are paying nearly 125% more on a CPM basis than a year ago. Wright says that reflects, in part, pharma’s tendency to purchase longer and more expensive inventory because of its creative and disclosure requirements.

Travel advertising CPMs are up about 55%, but Wright says the increase appears to reflect a change in media mix rather than broad-based inflation.

“If you were buying a display ad at $4, now you’re buying a video ad at $18,” Wright says. “That naturally will increase the price.”

Other advertisers are moving in the opposite direction. Household-supplies CPMs are down 21% year-over-year as buyers shift toward less expensive inventory. But Wright notes cheaper does not necessarily mean inferior inventory. For some advertisers, the goal is finding “more effective inventory” at a lower price.

That is particularly relevant as radio pitches advertisers on increasingly broad combinations of broadcast and digital products. Buyers aren’t simply deciding how much to spend digitally — they are continually changing the mix of platforms, formats and inventory they use to reach an audience.