Newcastle-based performance intelligence company Leaf Signal has published UK State of Tracking 2026, an audit of conversion tracking accuracy across 500 of the UK’s leading Shopify websites.
The audit checked whether those sites send Meta, Google Ads and GA4 the data they need to optimise and report accurately. Where they didn’t, they diagnosed why, using automated diagnostics and AI monitoring alongside manual verification of every result.
The headline finding was that 98% of brands audited had at least one crucial tracking issue, meaning a significant portion of the UK’s fastest-growing eCommerce brands are making ad targeting, bidding and budget decisions on inaccurate signal data.
Other key findings from the report:
• 52% of brands audited had missing core events entirely – the most critical issue as this leaves platforms with zero visibility into that stage of the journey
• 88% had missing parameters on live tracking events – so ad campaigns optimise against incomplete numbers
• 74% fired non-essential tracking before or without a visitor’s consent – a direct GDPR exposure
• 76% had three or more critical tracking issues at once
• Six retail verticals had a 100% broken-tracking rate – meaning every brand competing in those categories is currently optimising campaigns on broken data
The faults vary by platform and by retail vertical, but each affects the same underlying signals that ad platforms use for targeting and bidding decisions. As Meta and Google automate more of that decision-making, the accuracy of those signals becomes more relevant to how campaigns perform.
“Conversion tracking is the first and most important part of the performance marketing chain – but it’s also the most neglected,” said Wesley Hartley, Chief Commercial Officer at Leaf. “This report shows exactly how broken it is across UK eCommerce, and what it’s actually costing brands in CAC, ROAS and paid media profitability.”
The full report breaks the findings down further by issue type, retail vertical and ad platform, including which verticals and platforms come out best and worst.
UK State of Tracking 2026 is available to download now here. Brands that want to check where their own tracking stands can request a free tracking audit from Leaf Signal here.