The forecast: Among connected TV (CTV) companies we forecast, Hulu will lead in US ad revenues in 2021 at $3.13 billion, up 44% over 2020. Hulu has previously been the top earner for ad revenues and will continue to hold that position through our 2023 forecast.

Dive deeper:

• Hulu's share of the CTV video market has been gradually falling since 2017 as newer competitors draw some of the company's ad dollars
• Youtube, will accrue $2.54 billion in US CTV ad revenues in 2021, up 63% over 2020, marking exceptional performance for the platform and for its parent, Google.
• Meanwhile, Roku, another streaming company born directly from digital, is outperforming our previous expectations. The platform will net $1.58 billion in 2021 US ad revenues, up 92% from last year. An emerging growth area for Roku is the Roku Channel, its ad-supported channel that holds an increasing amount of content, including Quibi's bite-sized originals.

Looking ahead: Overall, CTV ad spend will exceed $14.4 billion in 2021, coming from a mix of new entrants in the subscription-based space as well as companies mentioned above.