Retail Media Networks: Where Brands Should Spend Beyond Google and Meta

According to eMarketer’s late-2025 forecast, U.S. advertisers will spend $69.33 billion on retail media in 2026. That is up from $58.79 billion in 2025. The more useful number is who gets the growth. eMarketer expects Amazon Ads and Walmart Connect to capture $9.42 billion of that $10.53 billion increase, or more than 89%. If your paid budget still splits between Google and Meta, retail media networks are now the third contender for it.

In my e-commerce work, the appeal has always come down to one thing: the retailer knows who bought. Search and social platforms keep losing purchase signals to privacy changes. A retailer, however, sees the transaction in its own systems. It can target with purchase history and report against actual sales. That closed loop is what you pay for with retail media networks.

What Retail Media Networks Sell

A retail media network is a retailer selling ads that run on its own shopper data. The inventory falls into three groups:

• On-site ads: sponsored product listings, search ads and display on the retailer’s site and app. Most budgets start here.
• Off-site ads: video, connected TV, social and display elsewhere, targeted with the retailer’s data and measured against its sales.
• In-store media: screens, audio and smart carts inside physical stores.

Most networks sell off-site inventory through a demand-side platform. So it helps to know programmatic buying basics before you sign an insertion order.

Amazon, Walmart Connect, Instacart and Others

Among retail media networks, Amazon is the largest by a wide margin. Its advertising revenue hit $21.3 billion in the fourth quarter of 2025, up 23%, according to its fourth-quarter earnings release. Adding up its four quarters gives about $68.6 billion for the year. Its reach also extends well past Amazon.com. In June 2025, Amazon Ads and Roku announced a deal for Amazon DSP advertisers. It offers logged-in reach to an estimated 80 million U.S. connected TV households.

Walmart Connect is growing faster from a smaller base. In February, Walmart reported that Walmart Connect in the U.S. grew 41% in the quarter that ended January 31, 2026. Its global advertising business grew 46% for the fiscal year, to nearly $6.4 billion. That total includes VIZIO, the TV maker Walmart now owns.

Instacart is the grocery specialist. Its advertising and other revenue reached $1.065 billion in 2025, up 11%. More than 9,000 brands advertised with it in the fourth quarter. Instacart also licenses its ad technology, called Carrot Ads, to other retailers. By its fourth-quarter 2025 letter, it counted more than 310 Carrot Ads partners.

After those three, the list gets long. Target’s Roundel, Kroger Precision Marketing, The Home Depot’s Orange Apron Media and Costco all sell ads. So do delivery apps such as Uber and DoorDash. Size matters less than overlap with your buyers, so start where your product already sells.

Off-Site and In-Store Placements

Off-site is where retail media networks compete head-on with Google and Meta. You buy video, CTV or social ads, target them with retail purchase data and measure them against real sales. For example, Instacart works with Google, Meta, Pinterest, TikTok and The Trade Desk. Through them, it reaches shoppers and ties that activity back to Instacart purchases. Similarly, when Walmart relaunched its ad business as Walmart Connect in 2021, it began selling shopper data through The Trade Desk. Retailer data is also one of the few durable audiences left for retargeting without third-party cookies.

In-store is the newest and least standardized piece. At its 2021 relaunch, Walmart Connect pointed to about 170,000 digital screens across more than 4,500 stores. More recently, Instacart began running shoppable display ads on its Caper smart carts. In December 2024, IAB and IAB Europe released in-store retail media standards. They divide a store into zones such as entrance, aisles and checkout. They also separate an ad that played on a screen from an ad a shopper was likely to see.

I treat in-store as a pilot budget for now. Before you scale it, ask for results from test stores compared against matched control stores.

Measuring Retail Media Networks for Incrementality

Reports from retail media networks tend to look strong. They credit every sale the retailer can see, including sales that would have happened anyway. For instance, a shopper who searches your brand on Amazon and clicks your sponsored listing probably planned to buy from you. That is the over-crediting problem behind most debates about how attribution models assign credit. It has the same answer here: a controlled test.

The IAB and MRC retail media measurement guidelines, finalized in January 2024, give you the language to ask for it. They require networks to disclose attribution windows before a campaign runs. They also require reporting at the placement level. For incrementality, they name randomized controlled tests as the preferred method.

Questions I ask every network before signing:

• What attribution window do you use, and does it count ad views or only clicks?
• Can you report new-to-brand sales separately from repeat buyers?
• Will you run a holdout test, and who designs the control group?
• Can I match results against my own customer data in a clean room? Instacart, for example, launched its Data Hub clean room with WPP Media and Pacvue.

Also split branded and non-branded sponsored search in every report. Branded terms defend your shelf, while non-branded terms are where new buyers come from.

Where the Budget Comes From

Decide where the money comes from before you spend it, because that changes how you judge results. If it comes from trade promotion, finance will compare it with shelf placement and discounts. If it comes from search and social, the comparison is your cost per acquisition on Google and Meta.

Also budget for the work around the media. Product images, Amazon A+ content, review programs and stock planning decide whether a sponsored click turns into a sale. When I plan a first quarter on a new network, I keep a share of the budget for that content work.

How to Start With Retail Media Networks

Once the budget has an owner, work through these steps:

1. Pick the one network where your product sells most today. For most brands, that means Amazon or Walmart.
2. Fix your product pages first: titles, images, reviews and stock. An ad cannot rescue an out-of-stock listing.
3. Start with sponsored product ads on your top sellers, with separate campaigns for branded and non-branded terms.
4. Agree on the attribution window and new-to-brand reporting before launch.
5. Add off-site only after on-site results hold up, and ask for a holdout test when you do.
6. Run in-store as a pilot with test and control stores.
7. Each quarter, compare cost per incremental sale across retail media networks, Google and Meta. Then move budget toward the cheapest.