Subscribe to our news letter
Last updated: June 2, 2026
For a marketplace, the ROI of retail media is not one number. It is the balance between three things that pull against each other: the high-margin ad revenue a network earns, the GMV it has to grow without cannibalizing, and the shopper experience it cannot afford to break. The good news is that the economics start in your favor, because retail media sells attention you already own, so a mature network can earn 5-10% of GMV in ad revenue without adding inventory or logistics. The hard part is measuring it honestly. Most reported returns use last-click attribution, which overstates the real number, and aggressive ad loads can quietly suppress conversion. This guide explains what the ROI actually is, how to measure it, and how to compare platforms before you commit.
Part of Osmos's retail media hub: Retail Media Evolution: The Complete Guide — with companion guides on where retail media is heading and monetizing shopper attention.
What is the ROI of retail media for a marketplace?
Retail media is one of the highest-margin revenue lines a marketplace can add. A mature network can earn between 5% and 10% of GMV in advertising revenue, and around 5% is a reasonable planning baseline. That revenue is largely incremental: it monetizes search results, product pages, and shopper attention the marketplace already has, so it does not add inventory, shipping, or returns the way more product sales would.
For the brands buying that inventory, the return shows up as ROAS, which commonly lands in the 3-6x range depending on platform and ad format, with sponsored search at the higher end. Those benchmarks come with a caveat covered below, so for the platform-by-platform numbers, see the retail media ROAS benchmarks guide. The short version: the marketplace earns margin on ad revenue, and the brand earns sales it can attribute, which is why both sides keep investing.
How do you evaluate the ROI of different retail media platforms?
Compare platforms on the same definition of a sale, or the comparison is meaningless. Two platforms can both claim a strong ROAS while counting completely different things, so before you trust any number, ask each one three questions.
- How do you attribute a conversion? Last-click within a short window flatters the number. Closed-loop attribution that ties the ad to an actual purchase is the one that matters. For how this works, see the guide to closed-loop attribution.
- Can you run an incrementality test? A platform that supports holdout groups can show the sales that would not have happened anyway. One that cannot is asking you to take its ROAS on faith.
- What is the take rate and the all-in cost? Yield to the marketplace and cost to the advertiser are two sides of the same ROI. A platform with a high take rate but weak measurement can cost more than it returns.
A platform reporting last-click ROAS will always look better than one reporting incremental ROAS, even when the second is the more honest business. Score them on attribution quality first, then on cost.
What is a good ROAS for retail media?
Industry ROAS commonly sits in the 3-6x range for established networks, meaning $3 to $6 in attributed sales for every $1 spent, with sponsored search higher and display lower. Treat that as a starting reference, not a target, because most of it is last-click. For platform and ad-format detail, the ROAS benchmarks guide breaks the numbers down.
The more useful question is incremental ROAS: the sales the ad actually caused. That number is almost always lower than the headline, and the industry is moving toward it. As Jason Wescott, Global Head of Commerce Solutions at WPP Media, puts it, "The overreliance on ROAS as the benchmark of value is over" (Skai, 2026).
The three numbers people call "ROI" measure different things. This is how to read each one before you compare platforms.
| Metric | What it measures | Why it can mislead | What to ask |
|---|---|---|---|
| Last-click ROAS | Sales credited to the last ad click | Overstates returns by counting sales that would have happened anyway | What attribution window and model? |
| Incremental ROAS (iROAS) | Sales the ad actually caused, measured with holdout tests | Usually lower than the headline; needs a proper test design | Can you run a holdout or incrementality test? |
| Ad revenue (% of GMV) | The network's own yield on the sell side | Ignores the effect on conversion and shopper experience | What is the take rate, and the effect on GMV? |
How should a marketplace measure retail media ROI honestly?
Measure two things at once: the ad revenue the network earns, and its effect on GMV and shopper experience. Measuring ad revenue alone overstates ROI, because a page packed with ads can lift short-term revenue while suppressing conversion and repeat purchase. The honest scorecard pairs ad yield with conversion rate, organic relevance, and repeat-purchase rate.
On the attribution side, the gap between reported and real is well documented, yet most teams have not closed it. Only about half of brands measure incrementality even at a basic level, and just 20% are good at both measuring it and acting on what they learn (Skai, 2026). That is also why measurement keeps topping priority lists: 86% of commerce media decision-makers call strengthening measurement and attribution a high or critical priority (Forrester, 2025). For a marketplace, the takeaway is simple: build incrementality testing in early, before ad revenue becomes a number leadership refuses to question.
Marketplace retail media ROI vs direct sales
A marketplace earns ROI on retail media differently from a first-party retailer, because it monetizes other sellers' GMV. Every third-party seller is a potential advertiser, so the addressable advertiser base scales with the marketplace itself. That is leverage a direct retailer does not have: a marketplace grows ad demand by adding sellers, while a direct retailer can grow it only by adding traffic.
The payback on launching or expanding a marketplace with retail media depends on three inputs: how many sellers adopt ads, the take rate on that ad spend, and how cleanly you can attribute results back to them. Sellers fund campaigns when they can see the return, so self-serve tools and clean attribution are not nice-to-haves; they are what turns seller GMV into ad revenue. Done well, retail media makes the marketplace model more profitable per unit of GMV than direct sales, because the ad margin sits on top of the commission.
Frequently asked questions
What is the ROI of retail media?
A mature retail media network can earn 5-10% of GMV in high-margin ad revenue, and brands buying that inventory typically see ROAS in the 3-6x range depending on platform and format. The exact return depends on whether you measure incremental sales or last-click attribution.
How do you evaluate the ROI of different retail media platforms?
Compare them on the same definition of a sale. Ask each platform how it attributes conversions, whether it can run incrementality tests, and what its take rate is. A platform reporting last-click ROAS will look better than one reporting incremental ROAS, even if the second is more honest.
What is a good ROAS for retail media?
Industry ROAS commonly sits around 3-6x for established networks, with sponsored search at the higher end and display lower. Treat headline ROAS with caution, because most of it is last-click; incrementality tests usually show the true number is lower.
How should a marketplace measure retail media ROI?
On two axes at once: the ad revenue the network earns, and its effect on GMV and shopper experience. Measuring ad revenue alone overstates ROI, because aggressive ad loads can suppress conversion and repeat purchase.
The ROI of retail media is real, but only if you measure it honestly: ad revenue on one axis, GMV and shopper experience on the other, with incrementality behind the ROAS. Marketplaces that build that discipline early compound it as they scale. Osmos helps marketplaces stand up measurable, high-yield retail media with Osmosphere. For the full picture, start with the retail media hub.
.png)
