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David Bailey is digital marketing lead at John Lewis & Partners, one of the U.K.’s largest retailers.
From loafers to sofas, shoppers turn to John Lewis for everything from everyday fashion or beauty purchases through to larger investment furniture pieces.
Search is a vital shop window for us: 60% of our sales now come through our digital channels. So it’s essential that we show up at the right time, with the right products and the right message — all while remaining profitable.
While our brand may be over 150 years old, our digital strategy has to keep moving at pace. Until recently, legacy systems meant we were dependent on unreliable data feeds, hampering our ability to optimise Search campaigns. This became an even bigger issue in peak moments such as Black Friday. It also meant performance measurement and reporting could be challenging.
Partnering with Jellyfish, we tackled these challenges head-on to ensure our digital shop window was always open for business.
Overcoming data challenges
When we initially switched our Search campaign strategy to prioritise profit instead of revenue, we knew it was the right move. This would help us maintain an edge in a fiercely competitive environment. But limitations in our legacy data feeds became apparent.
For instance, we only imported our data once a day. This meant that if there were any hiccups in the process, there would be knock on effects to our campaign performance. It looked as if we had no data one day, then twice as much the next. This caused inconsistencies in our bidding and pay-per-click (PPC) performance, leading to inefficient spending and missed opportunities.
We found ourselves often playing catch-up — trying to model the impact of traffic reductions or surges and ensuring stable spending. Our focus was diverted from strategic thinking and test-and-learn campaigns to manage day-to-day operations. This was especially challenging during peak shopping periods when there is greater consumer demand, placing greater strain on our data imports under the weight of the extra traffic and data.
[We] modelled the business impact of data issues and we outlined the added benefits of measuring performance and connecting with high-value shoppers.
Building a future-proof approach to data
Working closely with digital agency Jellyfish, we began the search for new ways to give us better control over our data collection, distribution, and measurement.
We adopted a tool called server-side Google Tag Manager (sGTM), which allows us to manage tags and data collection on our own servers rather than relying solely on the browser.
Using sGTM allowed us to track profit in real time, and it also meant we were able to leverage other measurement tools such as enhanced conversions and consent mode, filling any data gaps through modelling, leading to a more accurate view of ROI generated from Search activity.
To make this new approach a reality, we had to build buy-in across our teams, which meant building the strongest business case we could. In the end, this was quite easy, both because we’d modelled the business impact of data issues and we outlined the added benefits of measuring performance and connecting with high-value shoppers.
The whole project took 18 months from concept and brief to being fully rolled out, and included a robust testing protocol to ensure a smooth transition.
Pound for pound, we’re as optimal as we’ve ever been for paid Search.
Driving profitability and efficiency through data
For the immediate team, the hard work paid off. The new measurement foundation gives us greater control over our data. We have a more reliable data pipeline which addresses the stability issues and provides a foundation for more accurate measurement.
The approach was especially helpful over the peak retail season, with our campaigns around Christmas 2024 running smoothly.
But for the wider business, it smashed all expectations. We’ve seen average profit go up 20% across Search overall, and target return on ad spend increase by 4%. The sGTM profit feed also uses multi-touch attribution, which gives us a greater understanding of our campaign performance. It provides insights into customer demand, which we’re using to make decisions across the full funnel. We’re able to make “in-flight” decisions, which are particularly helpful around peak periods or new product launches.
Most importantly, the team can now work more strategically. We’re focusing on testing and learning, as well as campaign structures, to further help profitability in the months and years to come.
Pound for pound, we’re as optimal as we’ve ever been for paid Search. It’s underpinned by a sound measurement plan, and most importantly, we know that we’re reaching customers when they’re looking through our digital shop window for what we can offer.
And for our customers, their shopping experience is enhanced by John Lewis products showing up in the right places, at the right time — saving them time and effort seeking them out.
