System1 Reveals Top 10 UK OOH Ads as Outdoor Advertising Hits Record £31B Global Spend

Jul. 22, 2025

System1 has unveiled a list of the top ten UK out-of-home adverts ever tested on its platform, as the OOH market hits record revenues. In 2024, global OOH spending surpassed £31 billion, spurred on by the rising popularity of programmatic, improved personalisation, and growing reach.

According to System1, the top 10 UK OOH adverts are:

• Andrex “A Little Love Goes a Long Way” (5.9 Stars)
• Cadbury’s “Secret Santa” (5.5 Stars)
• Minute Maid “The Open Billboard” (5.2 Stars)
• Jaffa Cakes “We’re a Cake You Biscuit” (5.0 Stars)
• WWF “Prescription for Nature” – Park (5.0 Stars)
• KitKat “Have a Break” (4.6 Stars)
• Cornetto “Surf” (4.2 Stars)
• Cadbury’s “Caramilk” (4.2 Stars)
• Pringles “Let’s-a-go” (4.2 Stars)
• Walker’s Shortbread “A Wee Bit of Scotland” (3.8 Stars)

The list is based on System1’s ‘Test Your Ad’ platform, which predicts the long-term brand building potential of creatives based on their capacity to evoke strong, positive emotions. A score of 5.0 Stars or above indicates a high emotional response and is considered “exceptional”. The average rating for OOH adverts is 2.2 Stars.

Recent research by System1 and JCDecaux shows outdoor creatives which score over 3.0 Stars are twice as likely to drive consumer action and three times as effective at boosting brand sentiment. On the other hand, adverts which fail to evoke strong emotions are less memorable and less likely to have a positive commercial impact.

The ‘Test Your Ad’ platform also rates adverts on their short-term sales potential and Fast Fluency (how quickly audiences recognise the brand). Because the average viewer pays outdoor commercials just two seconds of attention, Fast Fluency is particularly important for out-of-home advertising. Well-branded adverts are over 50% more likely to be recalled, making them powerful drivers of long-term brand building and sales growth.

Andrew Tindall, SVP Partnerships, System1, said: 

"Outdoor is having a moment. Les Binet recently revealed it's now outperforming TV for reach, yet many brands still treat it as an afterthought. We partnered with JCDecaux UK to challenge that mindset. Because reach means nothing if people don’t feel something or remember who the ad was for. Our new research, Double Take, led by Beth Marchant at System1 in collaboration with JCDecaux, is packed with evidence on what truly works in outdoor. It’s the kind of insight that will make you completely rethink your creative approach."