Retail media spending is surging as advertisers explore new formats, channels and environments. With projections suggesting that in-store retail media ad spend alone will surpass $1 billion by 2029, the industry is entering a new phase of growth. However, confidence in measurement has not kept pace with this rapid expansion.
Viewing retail media through the lens of single campaigns or digital-only channels no longer reflects real-world shopping behavior. Last-click attribution, inconsistent measurement approaches across retailers and publishers and reporting that separates in-store, onsite, offsite and CTV activity into disconnected views create significant blind spots. These limitations make it difficult to connect online and offline behavior or distinguish true media impact from organic demand.
The future of retail media depends on a decisive shift away from siloed in-store and online metrics to a holistic, full-funnel approach that reflects how customers actually shop. Unlocking that future requires consistent, privacy-safe data that captures the complete path to purchase and establishes a new standard of precision and insight.
Unlocking the path to purchase
Progress begins with recognizing that not all data sets are equally useful. As retailers and advertisers work to close persistent measurement gaps, first-party relationships such as membership or loyalty programs have become critical. These programs provide consistent, consent-based signals across channels and transactions, forming the foundation for more reliable measurement.
Longitudinal measurement builds on this by tracking how groups of shoppers move through the path to purchase over time, rather than evaluating touchpoints in isolation. It uses aggregated, anonymized first-party data to connect verified digital and in-store transactions while meeting privacy and regulatory requirements.
Rather than assigning credit to a single click, this approach allows brands to evaluate how exposure drives discovery, consideration, trial, repeat purchase and loyalty across channels. With this level of insight, advertisers can better understand how media and merchandising reinforce one another and how digital, in-store and omnichannel experiences work together. It also closes a long-standing gap between upper-funnel engagement, including social and influencer activity, and verified sales outcomes over time.
Measuring outcomes over time
Retail media measurement must evolve beyond ROAS and short-term sales lift tied to individual campaigns.
Today, advertisers also need outcome-based metrics grounded in longitudinal, identifiable and privacy-compliant data. That includes new and incremental buyers, expanding baskets, increasing category penetration and improving retention, purchase frequency and loyalty.
Longer-term signals matter, too. Understanding how shoppers’ needs and behaviors change over time, and whether media experiences strengthen lifetime value and brand preference, provides a more complete view of effectiveness.
For example, a brand launching a new product may see limited immediate conversion from upper-funnel media. Over time, longitudinal measurement can reveal increased category entry, higher repeat rates or expanded baskets—outcomes that last-click models would otherwise miss entirely.
Omnichannel environments add complexity, but they also make measurement more meaningful. In-store media, onsite and offsite digital advertising, search and sampling programs often work in combination, while seasonal moments and curated experiences influence both immediate sales and longer-term affinity. Measuring their true value requires connected, privacy-safe measurement over time, not just clicks.
The future of retail media measurement
No single metric or model can answer every measurement question. Multi-touch attribution helps distribute credit across touchpoints, while media mix modeling reveals longer-term, cross-channel impact at the portfolio level. Incrementality and lift tests add another layer by isolating cause and effect for specific tactics or audiences.
When paired with closed-loop, transaction-based insights, these approaches enable a more complete evaluation of retail media effectiveness over time. Consistent definitions and methodologies, unified views across onsite, offsite, in-store and CTV and outcome-based KPIs are essential to building advertiser confidence.
Retail media will reach its full potential when impact is proven across the entire path to purchase. As investment continues to grow, the next era will belong to networks and advertisers willing to measure what truly matters and hold themselves accountable across the full funnel.
“Data-Driven Thinking” is written by members of the media community and contains fresh ideas on the digital revolution in media.
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