Retail media networks are projected to capture $175 billion in global ad spend by 2026, according to GroupM — a figure that now rivals the entire global TV advertising market. For programmatic practitioners still treating Amazon Ads, Walmart Connect, and Target's Roundel as bolt-on tactics, this is a structural shift that demands a full strategic reorientation before Q1 2026 planning locks in.
What You'll Learn
- How Amazon DSP, Walmart Connect DSP, and Roundel's programmatic stack differ architecturally
- CPM benchmarks and ROAS expectations across on-site and off-site retail media inventory
- Data clean room capabilities and first-party signal integration across all three networks
- How to integrate retail media into existing DV360, TTD, and GAM buying workflows
- Key strategic moves to make before 2026 budget cycles close
The Programmatic Architecture Behind the Big Three
Understanding retail media networks in 2026 requires treating each network as a distinct DSP ecosystem — not a walled garden afterthought. Amazon, Walmart, and Target have each built differentiated programmatic stacks with varying degrees of openness to third-party demand.
Amazon DSP: The Incumbent Infrastructure Play
Amazon DSP remains the dominant force, offering access to over 300 million active customer accounts with purchase-verified audience segments. Its programmatic stack now spans display, OLV, CTV (via Freevee and Fire TV), and audio, with real-time bidding across both Amazon-owned and third-party supply through Amazon Publisher Services (APS).
The 2025 rollout of Amazon Marketing Cloud (AMC) Query API gave agency trading desks the ability to run custom SQL-based audience analytics across impression and conversion data — a capability that's now table stakes for any sophisticated Amazon program. AMC clean room integration is also available via select CDPs including Salesforce and Adobe, enabling first-party data onboarding without raw data exposure.
Amazon's supply-side expansion through APS and its Publisher Cloud has created a programmatic loop where Amazon's shopper signals can now be activated against non-Amazon inventory — fundamentally changing the off-site retail media calculation.
Walmart Connect DSP: The Trade Desk Partnership Advantage
Walmart Connect's DSP infrastructure is built on a deep integration with The Trade Desk (TTD), giving media buyers a familiar interface while accessing Walmart's 145 million weekly omnichannel shoppers. Unlike Amazon's closed-loop system, Walmart's TTD-powered approach means buyers can unify Walmart audience segments alongside other TTD deal IDs in a single campaign structure.
Walmart's Luminate data platform, launched in 2023 and significantly expanded through 2025, now allows brand and agency partners to access SKU-level sales lift, household penetration metrics, and basket-level attribution — all accessible in a clean room environment compliant with CCPA and emerging state-level privacy frameworks.
The programmatic implications are significant: TTD buyers can now activate Walmart first-party segments against CTV inventory, DOOH (including Walmart in-store screens), and open web display through a unified campaign, with closed-loop attribution back to Walmart purchase data.
Target Roundel: The Off-Site Programmatic Challenger
Roundel has made the most aggressive off-site push of the three, with over 150 publisher partnerships including premium inventory on Disney, Spotify, and Pinterest. Roundel's programmatic model is fundamentally media-network-as-a-service — it licenses Target's first-party data (230 million guest profiles) and executes against it across both Target's owned properties and its extensive partner network.
From a buying workflow perspective, Roundel operates primarily through managed service with self-serve capabilities expanding via its API partnerships. DV360 buyers should note that Roundel inventory is accessible via select PG and PD deals — direct outreach to Roundel's partnership team is required to unlock deal IDs that aren't available through standard marketplace discovery.
CPM Benchmarks and Performance Data: 2025–2026
Retail media CPMs have stabilized after the sharp inflation seen in 2022–2023, but they remain at a significant premium to open exchange — justified by closed-loop attribution that open exchange simply cannot replicate.
| Network | Format | Avg. CPM Range (2025) | Avg. ROAS (Reported) | Attribution Window |
|---|---|---|---|---|
| Amazon DSP | Sponsored Display (on-site) | $4 – $9 | 4.5x – 8x | 14-day click, 1-day view |
| Amazon DSP | OLV / CTV (off-site) | $18 – $38 | 2x – 4x | 14-day view-through |
| Walmart Connect | On-site Display | $3 – $7 | 3x – 6x | 30-day click, 14-day view |
| Walmart Connect | CTV (via TTD) | $22 – $45 | 1.8x – 3.5x | 30-day view-through |
| Target Roundel | On-site Sponsored | $5 – $11 | 4x – 7x | 14-day click |
| Target Roundel | Off-site Programmatic | $14 – $28 | 2.2x – 4x | 14-day view-through |
Note: ROAS figures are self-reported via each network's attribution methodology and not directly comparable without normalizing for attribution window, category, and competitive set. Engage each network's measurement science team to establish custom KPI frameworks before committing budget.
When comparing retail media ROAS against your DV360 or TTD campaigns, always request incrementality testing (geo-holdout or conversion lift studies) from each network before using ROAS as a budget allocation signal. Amazon, Walmart Connect, and Roundel all offer incrementality measurement products — insisting on this before scaling spend separates sophisticated buyers from those inflating attributed revenue.
Data Clean Rooms: The Real Differentiator in 2026
The clean room arms race is reshaping how brands evaluate retail media network partnerships. All three major networks now offer clean room environments, but capability depth varies significantly — and this variance directly impacts measurement sophistication and audience portability.
Amazon Marketing Cloud (AMC)
AMC is the most mature clean room in the retail media space, with full SQL query access, custom audience creation, and cross-channel path-to-conversion analysis. In 2025, Amazon extended AMC to support multi-advertiser audience overlap analysis — allowing brands to understand competitive category dynamics within Amazon's shopper graph without raw data exposure. AMC also supports direct integration with AWS Clean Rooms for brands running their own data infrastructure.
Walmart Luminate + TTD Data Alliance
Walmart's clean room approach benefits from TTD's UID2 infrastructure, enabling pseudonymous identity matching between Walmart's CRM data and publisher audiences. Luminate's analytics layer sits above the clean room, offering pre-built dashboards for category share, new-to-brand metrics, and household-level purchase frequency — significantly reducing the SQL expertise barrier compared to AMC.
Roundel Data Vault
Roundel's clean room (internally branded as the Roundel Data Vault) is the most restricted of the three, with limited self-serve SQL access and primarily managed-service delivery of insights. However, its Disney partnership means brands running Roundel campaigns can access co-mingled reach and frequency data across Target.com and Disney streaming properties — a unique cross-publisher view not available through AMC or Luminate.
Integrating Retail Media Into Existing Programmatic Workflows
The operational challenge for agency trading desks and in-house programmatic teams is avoiding siloed execution. Retail media networks cannot be managed as separate budget lines disconnected from DV360, TTD, and CM360 infrastructure — not if unified frequency management and cross-channel attribution are priorities.
DV360 Integration Points
DV360 buyers can access Roundel and select Amazon inventory through Programmatic Guaranteed and Preferred Deal structures. However, Amazon DSP remains largely closed to DV360 direct activation — the recommended approach is running parallel campaigns with AMC as the cross-channel measurement layer, exporting AMC audience segments to CM360 for unified floodlight attribution. Google's PAIR protocol also allows DV360 advertisers to match first-party CRM data with publisher first-party data — including select Roundel publisher partners — in a privacy-preserving environment.
The Trade Desk Advantage for Walmart
For brands prioritizing Walmart Connect, TTD is the clear workflow winner. Walmart audience segments are natively surfaced in TTD's platform, deal IDs can be layered with cross-channel frequency caps, and Koa AI optimization can be applied across Walmart and non-Walmart supply simultaneously. TTD's Unified ID 2.0 also aligns with Walmart's identity infrastructure, reducing match rate degradation that plagues other DSP-to-retail-media integrations.
Strategic Priorities for 2026 Budget Planning
With retail media networks maturing from tactical overlays to strategic channel pillars, media planners approaching 2026 budgets need to reframe their allocation logic. The on-site vs. off-site binary is obsolete — the real framework is signal-richness vs. scale, and each network offers a different position on that spectrum.
- Audit your clean room readiness: If your brand's first-party data isn't currently flowing into AMC, Luminate, or Roundel's data environment, you're forfeiting the measurement differentiation that justifies retail media CPM premiums.
- Negotiate incrementality testing into your upfront commitments: All three networks will offer geo-holdout or conversion lift studies — make these a contractual requirement before Q1 2026 spend begins.
- Separate shopper marketing and brand budgets structurally: Retail media on-site formats perform to shopper KPIs; off-site CTV and display formats compete on brand metrics. Mixing these in a single ROAS target distorts optimization signals for both.
- Build TTD and DV360 deal libraries now: PG and PD deal IDs for Roundel and Walmart Connect need to be set up weeks in advance of campaign activation — don't let procurement timelines compress your Q1 launch windows.
- Evaluate category exclusivity deals: Both Amazon and Walmart offer category-exclusive sponsorship structures for premium placements. For top-spending advertisers in competitive categories, these can deliver outsized share-of-voice at negotiated CPM floors well below auction rates.
Conclusion: Retail Media Networks 2026 Demand Structural Change
Retail media networks in 2026 are not an evolution of shopper marketing — they are a fundamental restructuring of where deterministic purchase data, programmatic execution, and closed-loop attribution converge. Amazon DSP, Walmart Connect, and Target Roundel each represent distinct infrastructure bets, and the brands that win will be those that have made deliberate architectural choices about identity, measurement, and workflow integration — not those simply following CPM efficiency signals.
The immediate next steps are clear: audit your clean room connectivity across all three networks, pressure-test your TTD and DV360 deal structures for Walmart and Roundel access, and build incrementality measurement requirements into every 2026 retail media contract before ink dries. The programmatic professionals who treat retail media networks as a data and infrastructure problem — not just a media buying problem — will hold the structural advantage through 2026 and beyond.
