Legacy TV measurement tactics are losing relevance as CTV eclipses linear

CTV’s rise has compelled a measurement overhaul in the linear market. In 2024, the number of CTV viewers in the US surpassed the number of linear TV viewers, per our forecasts. As a result, advertisers are deploying more of their budgets on CTV, where they benefit from more real-time measurement signals. By 2027, more ad dollars will be directed to CTV than linear TV, according to our estimates. As advertisers attempt to optimize spending across TV and CTV—and the networks that span both—the ecosystem is slowly coalescing around tactics that facilitate cross-platform visibility into incremental reach and outcomes.

Combined, linear TV and CTV will account for about a fifth (19.7%) of total media ad spending in 2025. Nowadays, advertisers plan their linear and streaming investments alongside each other, just as major networks pitch their linear and streaming properties as complements. As linear and CTV converge—we’ll refer to them collectively as converged TV throughout this report—modernized audience measurement will fuel strategies for performance and brand advertisers alike. For example:

• Brand advertisers require accurate reach and frequency metrics. Because consumers now access content via dozens of platforms and devices, even tentpole events like award shows and live sports are more challenging to measure. As measurement catches up to consumer viewing habits, brands will have better information regarding where to reach incremental audiences and how to optimize frequency to drive awareness and consideration while mitigating waste.
• Performance advertisers rely on newer identity resolution capabilities. For performance advertisers, the size of the audience isn’t as important as the revenue generated from a campaign. Networks’ and measurement vendors’ identity graphs and first-party data integrations help facilitate the one-to-one attribution that informs optimization.

Read the full report, Ad Measurement Trends H1 2025.