The UK digital ad market grew 13% year-on-year in H1 2026 to £21.6bn, according to the latest Digital Adspend report produced by IAB UK in partnership with Mediasense.
This compares to just six years ago, when UK digital adspend totalled just £16.5bn for the full year, demonstrating the rapid increase in digital ad investment since the start of the Covid-19 pandemic.
It has come as media owners, even those in traditionally analogue channels like OOH, have increasingly invested in digital inventory to meet demand from advertisers for faster and easier media buying and outcomes-based measurement. This via automated planning and buying.
The vast majority of digital ads are now being bought programmatically; £71.2bn worth of digital adspend was bought this way in H1 2026, equivalent to more than four-fifths (81%) of the market, up three percentage points from the year prior period.
What’s behind double-digit digital ad market growth? With IAB UK’s Elizabeth Lane
“This isn’t only a story about digital getting bigger. Where that money is going is changing too,” said Elizabeth Lane, IAB UK’s head of insight.
Search remains the UK’s largest digital advertising channel, growing 10% year-on-year in H1 to £9.1bn, equivalent to 43% of the market. However, its growth is being outstripped by retail media and online video.
Retail media adspend grew 32% year-on-year in H1 to reach £2bn, the fastest-growing digital channel.
The study notes that advertisers are “increasingly looking beyond its roots as a performance channel close to the point of purchase”, with retailers working to better integrate first-party data earlier into the media planning process, and moving up the funnel with new ad inventory. Earlier this year, Tesco launched premium video inventory across its website and app in a bid to offer brand advertising opportunities to marketers.
Can retail media be a brand channel? With Tesco’s Tash Whitmey
Online video investment, meanwhile, rose 18% year-on-year to £5.1bn, now comprising one-quarter (24%) of the digital market.
A third of this figure was invested in what IAB UK defines as “TV+“, which encompasses any video content delivered to a TV screen via the internet.
Notably, however, the vast majority of digital adspend (71%, or £15.1bn) is on mobile formats.
The rest of the digital market is rounded out by display (up 9% year-on-year to £3.1bn), gaming (up 10% year-on-year to £700m), digital OOH (£500m), and audio (up 9% year-on-year to £200m).
Publishing, which sits within display, search and audio formats, also grew 4% year-on-year to £380m.
Lane continued: “Advertisers have far more ways to reach people digitally than they did even a few years ago, and we’re seeing that reflected in where budgets are moving.”
