Data-driven TV ads to turn up the volume as linear falls

TV advertising is shifting from one of the simplest channels to possibly the most complex, with the decline of linear TV and the growth of connected TV opening up myriad opportunities to target consumers with data-driven advertising across its numerous formats.

WARC’s latest Global Ad Trends: The changing shape of TV report explores a decade of adspend data to understand linear TV’s decline and CTV’s rise, and considers how an array of forces within data, device and creative will shape its future.

Between 2014 and 2024, linear TV adspend worldwide declined by 27.5% in absolute terms – extending to a 50.8% drop when adjusting for inflation. There are sector variations: linear TV spend for tech and electronics has fallen by 42%, while household and domestic products have increased by 12%.

Linear TV still commands more than three-quarters of all TV investment, however, increasingly brands are rebalancing TV spend towards CTV, which now accounts for nearly half of all TV usage in the US, according to a separate Nielsen report.

The total video market – excluding social video and YouTube – is forecast to take a 15.9% share of spend in 2025, with linear TV now representing just 12.4% of total adspend ($143.9bn), down from 41.3% in 2013 and is expected to drop to 11.3% next year to $139.1bn – the lowest since 2005.

And some marketers are showing significant intent to increase spend on CTV which is set to reach $39.9bn this year (3.4% of total share) and grow 3.6% in 2026 to $44.7bn.

Globally, 56% of marketers plan to boost OTT/CTV budgets, up from 53% in 2024, according to Nielsen’s 2025 Annual Marketer report, which suggests strong growth in the Americas, but less so in APAC and Europe.

While TV audiences as a whole are shifting decisively from linear to streaming, perhaps unsurprisingly, the changes appear to be starker among younger viewers.

In the UK, linear TV’s weekly reach has fallen by 10 percentage points since 2021, according to Ofcom figures, standing at 73.8%. In the US, older audiences still watch over two hours daily, compared to 81 minutes for 16–24s, according to GWI data.

The decline in user reach has been accompanied by an acceleration in advertising costs. While analysis shows a clear upwards trend in global average TV CPMs, that increase is especially pronounced in the UK, Germany and the US. In markets like Brazil and Japan, linear TV CPMs are lower today than they were in 2012, according to figures from WARC Media, the World Federation of Advertisers and ECI Media Management.

Consumers easily switch between video distributors and devices, but for advertisers, the definition of TV has never been more contested. What once was a stable, shared medium is fragmenting in both definition and delivery, which in turn is impacting planning. This means how TV is bought and measured is also being rewritten.

YouTube is making a concerted play for TV adspend. The platform earns a rapidly growing amount of revenue from ads displayed on CTV screens, and TV companies themselves are looking to boost monetisation by distributing content on YouTube.

In the US, YouTube viewing on TV devices recorded a 12.8% share, says Nielsen, rivalling that of broadcasters and streamers. In 2024, YouTube earned $36bn in ad sales across devices — more than all four US broadcast networks combined. The platform is looking to acquire sports IP to sustain this momentum and expand into sitcom-style programming.

UK TV measurement body Barb has begun to measure TV-set viewing of 200 YouTube channels, offering fresh insight into YouTube’s role as a TV player, but early results show relatively modest reach at a channel level with the top 20 dominated by kids’ shows.

As linear TV buyers and digital specialists often sit in separate siloes, with different ways of working, measurement remains the great bottleneck.

Broadcasters know that reach and frequency are no longer enough. In a world where big tech speaks directly to CFOs in the language of growth, TV ad sellers wish to prove outcomes, not just exposures.

The industry requires more standardised and robust measurement across all forms of TV, WARC insists and the next decade in TV will be defined by data convergence, device gatekeepers, platform-fit creative, and new buying models.

The integration of retail data with TV promises to redefine how brands approach campaigns, the report predicts. By next year, global retail media spend is forecast to exceed the total TV market, according to WARC Media. Retailers may increasingly assume the role of senior partners, with TV services an upper-funnel arm amid a full-funnel proposition. Broadcasters know that reach and frequency are no longer enough. Retail data can help TV to prove outcomes, and not just exposures.

Less standardisation of non-broadcast ad formats means fewer reasons to treat the 30-second spot as default. Some brands are experimenting with interactivity like QR codes, shoppable overlays, and gaming integrations. AI will also be a disruptor.

Small brands are a key target for TV media owners. The largest brands in the world spend on average 38% of ad budgets on TV; among smaller brands that falls to 9%. A shift to programmatic selling in CTV may open the medium to a new share of advertisers.

WARC Media head of content Alex Brownsell said: “There’s no doubt that linear TV’s role is slowly waning, both in viewing and adspend, as audiences shift to the expanding ecosystem of CTV. However, new players such as big tech and retail media sellers hope TV can help them win brand dollars, and smart TV makers are creating their own ad-funded TV channels.

“As consumers move seamlessly from one form of video to the next, advertisers are being challenged to reappraise how they define TV – be it a specific type of video ad format, a media owner or simply the largest screen in the home – with important implications for planning and buying, frequency management and measurement.”

TOPICS:advertising Connected TV data strategy data-driven marketing digital marketing Warc