Retail media crossed $61 billion in U.S. ad spend in 2026, and two platforms are fighting for the lion’s share of every incremental dollar: Amazon Advertising and Walmart Connect. Amazon built the category. Walmart is now methodically dismantling its monopoly on the conversation. For Shopify sellers pushing into wholesale, Amazon third-party sellers diversifying off-platform, and DTC founders hunting for profitable acquisition channels, the choice between these two networks has never been more consequential — or more nuanced.
This is not a close race on absolute scale. But on ROI, audience quality, and competitive saturation, the gap is narrowing faster than most agency media plans reflect.
How Do the Two Networks Actually Compare on Scale and Reach?
Amazon Advertising generated an estimated $56.2 billion in revenue in 2025, according to eMarketer’s February 2026 retail media forecast, representing roughly 76% of the U.S. retail media market. Walmart Connect, by comparison, posted $4.4 billion in global ad revenue for fiscal year 2026 (ending January 2026), up 34% year-over-year. That is a meaningful acceleration — Walmart Connect grew faster than Amazon Ads for the second consecutive year.
Amazon’s network reaches approximately 220 million unique monthly U.S. visitors across Amazon.com, Twitch, IMDb TV, and its DSP off-site inventory. Walmart’s addressable footprint is smaller — roughly 150 million unique monthly U.S. visitors online — but includes a physical store network of 4,600 U.S. locations generating first-party purchase data that Amazon’s digital-only infrastructure cannot replicate at the same depth of basket size and cross-category behavior.
| Metric | Amazon Ads | Walmart Connect |
|---|---|---|
| 2025/FY2026 Ad Revenue | ~$56.2B | ~$4.4B |
| YoY Revenue Growth | ~18% | ~34% |
| U.S. Monthly Unique Visitors | ~220M | ~150M |
| Avg. Sponsored Products CPC (Q1 2026) | $1.47 | $0.61 |
| DSP / Off-Site Inventory | Yes (Amazon DSP) | Yes (Walmart DSP, limited) |
| In-Store First-Party Data | No (Whole Foods limited) | Yes (4,600 U.S. stores) |
| Self-Serve API Access | Yes (Advertising API v3) | Yes (Walmart Ads API, 2025) |
| Minimum Managed Spend | $0 (self-serve); $50K+ (managed) | $1K (self-serve); $25K+ (managed) |
| Third-Party Tool Ecosystem | Mature (Perpetua, Skai, Quartile) | Growing (Pacvue, Skai, Flywheel) |
| Grocery / CPG Vertical Strength | Strong (Fresh, Pantry) | Very strong (in-store dominance) |
Where Does the CPC Efficiency Gap Actually Matter?
The most operationally significant number in the table above is CPC. Amazon Sponsored Products averaged $1.47 per click in Q1 2026, per Pacvue’s Q1 2026 Retail Media Benchmark Report — up 22% from Q1 2025. Walmart Connect’s equivalent placement averaged $0.61. For a brand spending $50,000 per month on sponsored search, that spread translates to roughly 49,000 more clicks on Walmart’s network at equivalent budget.
But raw click volume is not the whole story. Amazon’s conversion rates on Sponsored Products hover around 12–14% for established brands in competitive categories, according to Jungle Scout’s 2026 State of the Amazon Seller data. Walmart’s on-site conversion for sponsored placements averages 8–10% in comparable categories. The gap narrows when you account for Walmart’s lower average basket competition and thinner incumbent brand saturation in many subcategories.
“We shifted 20% of our Amazon Ads budget to Walmart Connect in Q4 2025 and saw ROAS jump from 3.1x to 5.4x on that incremental spend. Amazon is still our volume machine, but Walmart is where we’re finding efficiency right now.” — Danielle Cho, VP of Performance Marketing, Grounded Home Co. (DTC home goods brand, $28M annual revenue)
That kind of arbitrage story is spreading fast through agency channels. Flywheel Digital, which manages over $2 billion in retail media spend, reported in its March 2026 client benchmark that brands allocating 15–25% of retail media budgets to Walmart Connect are seeing blended ROAS improvements of 18–31% versus Amazon-only strategies in the home, CPG, and personal care categories.
Which Platform Has the Better First-Party Data Infrastructure?
This is where Walmart’s offline footprint becomes a genuine structural advantage — not a talking point. Walmart processes approximately 37 million in-store transactions daily across its U.S. stores. That purchase data feeds Walmart Connect’s targeting segments in near-real-time, enabling audience overlaps that Amazon simply cannot build from digital behavior alone.
For CPG brands, this is decisive. A laundry detergent brand can target Walmart Connect audiences based on verified in-store purchase recency, frequency, and switching behavior — data that reflects what shoppers actually put in their physical carts, not just what they browsed. Amazon’s equivalent targeting relies on Amazon Fresh and Pantry purchase data, which covers a far smaller base of grocery buyers.
Amazon has responded with its own data investments. Amazon Marketing Cloud (AMC), now in its third major iteration, allows advertisers to run custom SQL queries across impression, click, and purchase data in a privacy-safe clean room environment. AMC is genuinely powerful for multi-touch attribution and audience suppression — tools that Walmart’s clean room offering, launched in beta in late 2025, has not yet matched at scale.
“AMC is still the most sophisticated clean room in retail media, full stop. But Walmart’s in-store signal is a different kind of data asset — and for brands that sell across both channels, ignoring it is leaving money on the table.” — Marcus Reilly, Managing Director of Retail Media, Skai
How Does Each Platform Handle Brand Discovery vs. Performance?
Amazon’s ad product suite has matured into a full-funnel stack: Sponsored Products for bottom-funnel search capture, Sponsored Brands and Sponsored Display for mid-funnel consideration, and the Amazon DSP for upper-funnel programmatic reach across Amazon-owned and third-party inventory. The ecosystem is deep. It is also expensive at every layer.
Walmart Connect’s product set has expanded significantly since 2024 but remains more performance-weighted. Its core products include:
- Sponsored Products: Search and browse placements on Walmart.com and the Walmart app — the primary driver of Connect revenue today
- Sponsored Brands: Header banner placements, rolled out broadly in 2025 — still lower competition than Amazon equivalents
- Display Ads: On-site and off-site display via Walmart’s DSP, now integrated with The Trade Desk via a direct partnership announced in Q3 2025
- In-Store Digital: Self-checkout screen ads and in-store TV network placements — a unique inventory type with no Amazon parallel
- Walmart Influencer Commerce: Integration with Creator.co for affiliate-style product seeding, still in limited rollout as of June 2026
The Trade Desk integration is worth flagging. It effectively gives Walmart Connect buyers access to TTD’s $10B+ programmatic ecosystem with Walmart’s first-party purchase data as the targeting layer — a combination that competing retail media networks cannot yet replicate. Early adopters in the CPG and home improvement verticals are reporting this as a meaningful upper-funnel unlock.
Which Network Should DTC and Shopify Brands Actually Prioritize?
The honest answer is that most DTC founders and Shopify sellers are not eligible to advertise on Walmart Connect without a Walmart Marketplace seller account — and Walmart’s marketplace approval process remains selective. As of Q1 2026, Walmart Marketplace had approximately 150,000 active third-party sellers versus Amazon’s 2.3 million. That selectivity is a feature for approved sellers (less competition, lower CPCs) and a hard wall for everyone else.
For brands that qualify on both platforms, the strategic allocation logic emerging from top agencies like Tinuiti, Wunderman Thompson Commerce, and Flywheel Digital in 2026 looks roughly like this:
- Amazon-first brands (high Amazon revenue concentration): Maintain 75–80% of retail media budget on Amazon; allocate 15–20% to Walmart Connect for efficiency arbitrage and new customer acquisition
- Omnichannel CPG brands: Increasingly shifting toward 60/40 or even 55/45 Amazon-to-Walmart splits in grocery, cleaning, and personal care categories where Walmart’s in-store data creates measurable targeting lift
- Emerging DTC brands entering wholesale: Use Walmart Connect from day one to build brand awareness with Walmart’s lower-income and suburban household segments — audiences that skew differently from Amazon’s Prime base
- Amazon-only sellers: Focus on AMC optimization, Sponsored Display retargeting, and DSP audience suppression before diversifying; Walmart requires operational infrastructure investment to unlock
“The brands getting hurt are the ones treating Walmart Connect like a smaller Amazon. It’s not. The shopper intent signals are different, the category dynamics are different, and the creative that works is different. You need to build it as a separate channel, not a syndicated one.” — Jordan Fisk, SVP Retail Media, Tinuiti
What Does the Competitive Trajectory Look Like Through 2027?
eMarketer’s June 2026 forecast projects Amazon Ads reaching $67 billion in revenue by 2027, while Walmart Connect is projected to hit $6.8 billion — still a 10-to-1 gap on absolute dollars, but one that represents continued share erosion for Amazon in the retail media category.
Three structural forces favor Walmart Connect’s continued growth: the maturation of its Walmart+ membership base (now at 38 million members, up from 32 million in 2025), the full commercial rollout of its in-store digital ad network in 3,200 stores by Q4 2026, and the ongoing Trade Desk integration unlocking programmatic demand that Walmart’s internal sales team could never have sourced alone.
Amazon’s counterplay is AMC scale, the continued build-out of Amazon Publisher Services for off-site reach, and — critically — the expansion of Amazon’s own physical retail footprint through Amazon Fresh and Whole Foods, which gives it incrementally more in-store purchase data to compete with Walmart’s transactional signal advantage.
For sellers and brands operating in 2026, the practical verdict is this: Amazon Ads remains the essential buy for anyone selling on Amazon — the platform’s own algorithm continues to reward ad spend with organic rank lift, making it structurally non-optional for most categories. But Walmart Connect is no longer a test-and-learn line item. For eligible sellers with the operational infrastructure to support dual-channel retail media, it is fast becoming a required allocation — and in several categories, the better-performing one.
