Connected TV (CTV) and online video advertising in the UK have moved beyond their growth phase into a crucial stage of structural maturity.
As part of NDA’s CTV and Online Video Spotlight month, we’ve looked at some of the biggest research reports over the last quarter, including the IAB UK and MediaSense Digital Adspend Report, the Advertising Association and WARC Expenditure Report, primary buy-side research from Rakuten TV Enterprise, and cross-media measurement data from ISBA Origin to provide a definitive overview of current spending trends, operational challenges, and strategic opportunities.
For agency planners, brand marketers, and media owners evaluating their Q4 allocations and 2027 strategy, these key datasets outline the current landscape.
Expenditure Benchmarks: Video drives total digital growth
The overall macroeconomic climate for UK digital advertising remains remarkably resilient.
According to the latest figures from the Advertising Association and WARC Expenditure Report, total UK ad spend is on track to pass the £50 billion threshold. Digital formats now account for nearly 86% of all media investment in the country.
Within this growth, video formats represent the primary growth area. The IAB UK and MediaSense HY 2026 Digital Adspend Report revealed several significant spending milestones:
- Total Digital Ad Market: UK digital ad spend reached £21.6 billion in H1, reflecting a robust 13% year on year increase.
- Online Video Expansion: Spending on online video surged by 18% year on year to £5.1 billion. Video continues to outpace standard static display as budget allocations move toward high-impact visual formats.
- The Surge of TV+: Within the video category, the TV+ segment, which encompasses Broadcaster VOD (BVOD), Subscription VOD (SVOD) ad-supported tiers, Free Ad-Supported Streaming TV (FAST), and YouTube on connected TV screens, grew by 22% year on year to £1.7 billion. TV+ now represents roughly one third of all digital video expenditure.
- Mobile Domination: Mobile devices continue to capture the vast majority of digital budgets, accounting for £15.1 billion, or 71%, of total digital spending across search, video, and display.
These figures show that while mobile remains the primary channel for sheer volume and frequency, CTV has established itself as the preferred platform for high-impact brand marketing.
High intent meets supply chain friction
While media spend data shows sustained growth, buy-side research highlights that programmatic CTV continues to face technical and operational challenges.
A study conducted by Rakuten TV Enterprise among UK senior marketing decision-makers reveals strong commercial intent alongside persistent structural challenges:
- Budget Expansion: A total of 74% of surveyed UK marketers plan to increase their CTV investment over the next 12 months, with 63% planning moderate increases and 11% planning significant budget expansions.
- The Transparency Barrier: Despite strong investment intent, 42% of respondents cited transparency as the single biggest obstacle preventing higher budget commitments. Supply chain complexity followed closely at 39%.
- Quality and Measurement Concerns: Specific transparency issues were led by viewability concerns at 30%, alongside concern over ad fraud, limited audience insights, and inconsistent signal passing across supply paths.
Scale, reach, and the shift to premium ad tiers
The rapid expansion of ad-supported streaming tiers from global platforms like Netflix, Disney+, and Amazon Prime Video has fundamentally reshaped audience dynamics in the UK.
Audience viewing data from BARB (Broadcasters’ Audience Research Board) shows that while global SVOD ad tiers have rapidly built scale among younger demographics, traditional UK Broadcasters (PSBs) retain a distinct advantage in single-program reach.
For example, top-performing titles on broadcaster platforms like ITVX, Channel 4, and My5 consistently generate larger individual audience reach figures than SVOD ad-tier content.
Therefore, media buyers are adopting a dual-track strategy:
- Broadcaster VOD (BVOD) for Massive Local Reach: Broadcaster platforms remain essential for broad household reach, cultural alignment, and high-volume live events.
- SVOD and FAST for Niche Targeting and Incremental Scale: Ad-supported tiers on streaming platforms delivering high-frequency targeting to light TV viewers and cord-cutters who rarely engage with linear broadcast channels.
Furthermore, long-term effectiveness studies from Thinkbox underscore the commercial value of total TV environments, demonstrating that television and premium VOD generate 54.7% of all advertising-driven profit in the UK, delivering higher long-term return on investment than pure performance digital channels.
Measurement breakthroughs: Deduplication and attention
As video consumption fragments across social platforms, broadcaster apps, and streaming services, cross-media measurement has moved from a theoretical preference to an operational necessity.
Recent analysis from Teads and Censuswide found that ad frequency duplication across siloed video platforms wastes approximately 10% of total media budgets. To combat this inefficiency, the UK market is pioneering new approaches to cross-screen evaluation:
- ISBA’s Origin Initiative: The UK’s cross-media measurement platform, ISBA Origin, continues its roll-out across major agencies and publishers. By establishing deduplicated reach and frequency metrics across linear TV, CTV, YouTube, and Meta, Origin provides buyers with an independent baseline to assess true campaign incrementality.
- Attention Metrics in Practice: Attention-based media planning is gaining traction across UK media agencies. Comparative studies show that while short-form social video delivers high impression volume at lower CPMs, CTV inventory yields significantly higher active attention time and message recall.
- Gen Z Cross-Screen Engagement: Research focused on younger demographics found that Gen Z audiences display 67% higher purchase intent when exposed to integrated video campaigns that combine social short-form video with high-definition CTV formats.
Benchmark Comparison: UK Video and CTV Research Summary
| Research Source | Primary Focus | Key Metric or Finding | Industry Implications |
|---|---|---|---|
| IAB UK / MediaSense | H1 Digital Market Expenditure | Online video reached £5.1bn (+18% YoY); TV+ reached £1.7bn (+22% YoY). | Video is outpacing total display growth, with TV+ capturing one third of total video spend. |
| AA / WARC Report | Full-Year Market Projections | UK ad spend pacing toward £50bn+; TV VOD growing at +13.8% YoY. | CTV and addressable formats remain the primary growth drivers across total UK media. |
| Rakuten TV Enterprise | Buy-Side CTV Survey | 74% plan budget increases; 42% cite transparency as their top barrier. | Scale depends on direct supply paths, verified inventory, and cleaner signal passing. |
| Thinkbox Research | Channel Profitability & ROI | TV and VOD generate 54.7% of all advertising-created profit in the UK. | Premium long-form video maintains superior long-term brand equity compared to display. |
| Teads / Censuswide | Omnichannel Efficiency | Duplicated video reach wastes approximately 10% of overall campaign spend. | Cross-platform frequency capping is essential to prevent ad fatigue and budget waste. |
The data underlines how Connected TV and digital video have firmly established themselves as the core drivers of UK media strategy. As technical transparency and measurement frameworks continue to mature, brands that master cross-screen execution will capture a distinct competitive advantage.
