Executive Summary
Retail media has entered its programmatic era. According to eMarketer (2024), programmatic retail media—ads powered by retailer data on third-party inventory—will represent more than 30 percent of North American retail-media spend by 2025.
Two platforms now dominate this space: Amazon DSP and Walmart DSP.
Both enable advertisers to extend shopper-data targeting beyond the retailer’s site, but their data models, reach, and strategic roles differ in ways that matter for CPG marketers allocating budgets across networks.
1. From On-Site to Audience Extension
The first wave of retail media revolved around sponsored products and in-site banners. The next is audience extension—using retailer data to reach those same shoppers across the open internet.
As McKinsey (2023) notes, this shift moves retail media “from conversion channel to full-funnel ecosystem.” Amazon and Walmart now offer DSPs that merge first-party shopper data with display, video, and connected-TV inventory—yet their architectures reflect different philosophies.
2. Amazon DSP: Scale and Closed-Loop Precision
Data foundation.
Amazon DSP draws on one of the world’s largest first-party datasets spanning Amazon.com, Prime Video, Twitch, and Alexa devices. Advertisers can target by purchase history, browsing behavior, or lifestyle segments and measure outcomes through Amazon Marketing Cloud (AMC).
Amazon Ads (2023) reports that campaigns using AMC for audience planning deliver up to 25 percent higher optimization efficiency than those run without it.
Inventory and reach.
The DSP provides access to both Amazon on-site placements and Amazon Publisher Services (APS)—a premium network of external publishers. It’s suited to awareness, retargeting, and sequential messaging inside a single, privacy-safe environment.
Strategic fit.
Amazon DSP excels where scale and closed-loop attribution matter most: driving re-engagement among known Amazon shoppers and linking ad exposure directly to sales. Its limitation is interoperability—data seldom leaves Amazon’s ecosystem.
3. Walmart DSP: Transparency and Omnichannel Flexibility
Powered by The Trade Desk.
Launched in 2021, Walmart DSP combines Walmart’s shopper data with The Trade Desk’s open-web infrastructure, connecting advertisers to over 80 million U.S. households.
The Trade Desk (2024) reports that campaigns using Walmart shopper audiences achieve 20–30 percent higher on-site conversion versus cookie-based targeting.
Inventory and identity.
Through The Trade Desk, advertisers access open-web, video, and CTV inventory while maintaining deterministic targeting via Unified ID 2.0 (UID2)—a privacy-compliant alternative to third-party cookies.
Strategic fit.
Walmart DSP favors brands seeking omnichannel attribution and transparency. It integrates naturally with third-party measurement tools and links online exposure to in-store sales.
Its trade-off: less global reach and fewer proprietary analytics than Amazon’s stack.
4. Comparing the Platforms
| Dimension | Amazon DSP | Walmart DSP (via The Trade Desk) |
|---|---|---|
| Data | Closed Amazon first-party data | Walmart first-party data in open-web environment |
| Identity | Amazon ID (closed) | Unified ID 2.0 (open, privacy-forward) |
| Measurement | Amazon Marketing Cloud | The Trade Desk + third-party tools |
| Inventory | On-Amazon + APS publishers | On-Walmart + open-web & CTV |
| Best for | Scale & deep funnel insight | Transparency & cross-channel reach |
| Geography | Global coverage | Primarily U.S. and Canada |
5. Strategic Implications for CPG Leaders
1. Use both platforms as complements.
Amazon DSP delivers scale and direct-commerce data; Walmart DSP offers openness and cross-retailer reach. Mature advertisers are balancing the two to blend depth (Amazon) with breadth (Walmart) rather than treating them as substitutes.
2. Standardize measurement.
Each DSP reports different metrics. McKinsey (2023) advises brands to create a unified retail-media framework with consistent KPIs—ROAS, incremental reach, new-to-brand—to compare efficiency across networks.
3. Integrate content and media.
Ads perform only as well as the product detail pages they drive to. Profitero (2023) found that optimized PDPs lift conversion by up to 20 percent across major retailers. Align creative, messaging, and PDP experience before scaling DSP investment.
4. Leverage data collaboration tools.
Amazon’s Marketing Cloud and Walmart’s partnerships with LiveRamp and The Trade Desk enable clean-room analysis—critical for managing overlap, reach, and frequency.
WARC (2023) highlights that early adopters of clean-room analytics see measurable gains in media efficiency through reduced duplication.
6. Outlook: Two Paths to Scale
Amazon and Walmart are converging on similar goals—linking retail data with premium media—but their approaches remain distinct.
Amazon will deepen its CTV integrations via Prime Video Ads, reinforcing a closed-loop system where awareness and conversion share one dataset.
Walmart will continue emphasizing interoperability, giving advertisers control and transparency across open-web environments.
For CPG leaders, the competitive question is no longer which DSP to choose but how to orchestrate both under a single retail-media strategy.
Those who unify governance, measurement, and creative execution across these platforms will capture the true advantage of data-driven retail marketing.
Published by Commerce Media Agency, powered by geekspeak Commerce - combining two decades of ecommerce expertise with deep commerce media strategy and content execution capabilities.