How Waitrose discovered the true value of display advertising

Waitrose Case Study - Image


Challenge is the online grocery site for one of the UK’s leading supermarkets. Following the successful launch of the website in 2011, the company has seen a significant growth in revenues, with accounting for an increasing portion of overall revenue, growing 41.4% over the past financial year.

Key to’s strong performance is its internal willingness to take an innovative approach to digital marketing. This is apparent in its display advertising strategy, with, in 2012 it being one of the first advertisers to embrace programmatic with its partnership with Infectious Media, the programmatic advertising specialist,

In early 2014, began to increase the efficiency of its digital marketing channels by getting a deeper understanding of how they added to sales. With this goal in mind, tasked Infectious Media with measuring the true value of display to develop a new way of improving its advertising to maximise sales.

Infectious Media worked closely with to devise a way to overcome this challenge. The first step was to determine the impact, if any, the ads were having on customers. This was defined as the sales that would not have happened without the customer seeing the ad. This would allow Infectious Media to refine their focus to what really mattered, increasing sales and reducing wasted ads to deliver more revenue for the same spend.

Infectious Media thought that the key to changing customer behaviour was showing viewable advertising. To demonstrate this it monitored the difference between users who were shown a viewable ad (50% of the ad in-view for 1 sec – IAB) and those who were shown a non-viewable ad in the same campaign. Once the behavioural difference was recognised, Infectious Media aimed to use viewability as a key factor in its targeting and optimisation to increase revenue, something that could only be done programmatically.


Infectious Media compared users who had been shown one or more viewable ads with users who had been shown one or more non-viewable ads, looking at onsite behaviour and sales.

Infectious Media discovered that sales from customers who were shown viewable and non-viewable ads were exactly the same. Meaning that regardless of whether a customer had seen an ad or not, they would still have purchased. Sales customers who had been shown an ad has been the industry standard for measuring the success of display for a number of years. This discovery exposed the standard as fundamentally flawed.

Through extensive testing and analysis Infectious Media made a breakthrough, the factor that had the biggest impact on customer sales was the number of viewable ads served to a user (see supporting material). To be more specific, Infectious Media found that its programmatic display advertising delivered an uplift in sales once a user was served with 5 or more viewable ads in one month.

This second finding highlighted that serving viewable ads to users at a low frequency level was just as wasteful as serving non-viewable ads to users.

Once this discovery had been made Infectious Media was able to change its optimisation strategy to focus on finding the ideal number of viewable ads to show customers. It saw an instant increase in the number ‘incremental’, or original, sales as the campaign optimised.

This innovative approach enabled Infectious Media to measure, report on and optimise directly to the sales that could be directly attributable to advertising. By disregarding users on whom the advertising had no impact ensured sales were maximised and wastage caused by non-viewable and low frequency ads was minimised. had full transparency on campaign performance, with full access to dashboards showing performance of the different audience segments, domains, times, days, regions and creatives.


Infectious Media’s approach to measuring the impact of display by identifying the right number of viewable ads to show customers ultimately delivered the following results:

  • 365% uplift in revenue from incremental sales over 3 months from a consistent budget
  • 460% uplift in the final month of the campaign in comparison with the last pre- campaign month

“We are delighted with the outcome of our latest campaign with Infectious Media. We have taken a huge step forward in understanding the true impact of our display advertising on our business, whilst driving efficiency. We are very proud to be the first advertiser to both solve this challenge and to adopt this new way of advertising.” Caroline Kinsman, Manager, Online Marketing, Waitrose