US CTV ad spending to hit $37.95B as upfronts overtake linear

The transition of upfront dollars from linear to digital signifies a permanent realignment of the television buying cycle toward flexible, data-driven environments. As programmatic execution becomes the default for 90% of the market, publishers must solve for fragmentation across devices to maintain pricing power against walled gardens. This shift forces a move away from simple impressions toward attention-based metrics, which 55% of marketers now view as the emerging industry standard. Watch for the adoption rate of Agentic AI in ad operations as a key indicator of how quickly publishers can automate cross-platform performance attribution.

The connected TV advertising ecosystem is grappling with transparency and measurement challenges as spend accelerates. Google's DSP began offering household-level targeting and conversion measurement for CTV campaigns in March 2025, a move aimed at achieving parity with competitors like The Trade Desk that already provide household-level options. The IAB Tech Lab has spent more than a year investigating whether CTV ads are actually being delivered to connected TVs and watched in real households, highlighting persistent verification gaps that threaten advertiser confidence as budgets shift from linear.

On the measurement and accountability front, the IAB released a guide in October 2025 urging industrywide adoption of standardized Conversion APIs for CTV. The report found that two-thirds of advertisers improved ROAS after implementing CAPI, while 75% of advertisers using a CAPI said they would reallocate budgets based on conversion performance. However, 72% of publishers cited technical complexity as a barrier to adoption, underscoring the fragmentation that continues to slow CTV's maturation as a performance channel. IAB CEO David Cohen warned that without standardization, CTV platforms will lose performance budgets to more measurable channels like search and social.

Buy-side sentiment reflects both enthusiasm and anxiety about CTV's measurement readiness. IAB's 2025 Outlook Study projected CTV spend growth of 13.8% for the year, with 54% of buyers planning to allocate a greater share of budgets toward performance campaigns over brand building. A separate industry best-practices document from CIMM published in July 2025 cited a Kargo case study showing a 54% attention lift for enhanced CTV formats versus traditional 15-second TV spots, while a CMI Media Group and Innovid campaign demonstrated that supply path optimization could reduce ad tech fees by 80% and reinvest savings into 5.3% more incremental impressions. These data points illustrate the industry's push to justify CTV's premium CPMs through verifiable performance outcomes.