Mercado Ads is Mercado Libre's advertising platform. It lets you pay so your listings appear ahead of your competitors'. It works, but it has a catch: the dashboard shows sales attributed to advertising, not whether those sales actually made you money. In this guide you'll see which products Mercado Ads offers, how Product Ads campaigns work, what changed with target ROAS, and how to calculate the minimum ROAS you need based on your real margin.
The short answer
- What it is: advertising inside Mercado Libre. Your products appear at the top of search results and in featured positions.
- How you pay: the spend on a Product Ads campaign is the total cost of the clicks your ads received.
- How you control it: with campaigns, a budget, and a target ROAS, which replaced the target ACOS.
- When it makes sense: when your product's margin, after the sales fee, shipping, and taxes, leaves room to pay for ads. If it doesn't, you're buying sales at a loss.
What products Mercado Ads includes
According to the official Mercado Ads documentation, there are three:
| Product |
Who it's for |
Where it appears |
| Product Ads |
Any seller who has it enabled |
Promoted listings in relevant positions in search results |
| Brand Ads |
Sellers and brands with an official store |
"Position 0": three of the brand's products ahead of Product Ads |
| Display |
Advertisers with direct or programmatic buying |
High-impact spaces on Mercado Libre and Mercado Pago |
For most small and medium businesses selling on Mercado Libre, the conversation is about Product Ads. If your account doesn't have it active, the documentation says it's enabled from My profile > Advertising.
How a Product Ads campaign works
Automatic or custom
The Product Ads documentation (updated October 19, 2026) describes two management modes:
- Automatic: the mode you start with. Mercado Libre chooses listings with good sales levels and shows them in the top positions. You can add or remove listings manually.
- Custom: you create several campaigns, each with its own budget and goal. The documentation itself calls this the ideal approach because it gives you control to adjust based on performance.
Our approach: group by margin, not by category. Products that leave 35% and products that leave 12% can't have the same target ROAS.
Budget
The budget you see is the daily average of a monthly budget. If one day doesn't use the full amount, the rest is spent on the following days until the end of the month. It updates every day at 4:00 (Argentina time).
Unified variants
According to the documentation, with the new flow all variants of a product (sizes, colors, catalog listings) are managed in a single campaign. The best-performing variant sets the baseline, and pausing or editing affects all of them.
Stock
A listing with an availability lead time (made to order) doesn't appear as an ad: products with immediate stock get priority.
Target ROAS: what changed and how to set it
Mercado Ads now prioritizes ROAS over ACOS. According to the developer documentation, campaigns that used target ACOS were automatically migrated to their equivalent target ROAS. The API started returning target ROAS in January 2026 and kept target ACOS as a reference until March 30, 2026. The relationship between the two is:
ACOS = (1 / ROAS) x 100
A ROAS of 5 equals an ACOS of 20%: you spend ARS 1 for every ARS 5 in attributed sales.
The calculation the dashboard doesn't do: your break-even ROAS
Target ROAS isn't chosen by looking at what competitors do. It comes from your margin:
- Calculate the pre-advertising margin of each product: sale price minus product cost, sales fee, fixed cost per unit, shipping you cover, installments, and taxes. We explain it step by step in how to calculate your real margin on Mercado Libre.
- Break-even ROAS = 1 / pre-advertising margin. At that ROAS, ads eat your entire margin and you make zero.
- Target ROAS = 1 / (pre-advertising margin - profit you want to keep).
Hypothetical example: a product priced at ARS 50,000 that, after all costs, leaves you 20% (ARS 10,000) before advertising.
| Profit you want to keep per sale |
Maximum advertising |
Target ROAS |
Equivalent ACOS |
| 0% (break-even) |
20% |
5 |
20% |
| 5% |
15% |
6.7 |
15% |
| 8% |
12% |
8.3 |
12% |
If the ROAS your campaign achieves is below break-even, every ad-driven sale costs you money. Raising the budget doesn't fix that; it just makes the problem bigger.
Which metrics to watch
The documentation splits sales into three types, and the difference matters:
- Direct sales: the person clicked the ad and bought that same product.
- Indirect sales: they clicked an ad and bought another of your products.
- Sales without advertising: sales of your promoted listings that didn't come from an ad click.
Two checks we recommend every month:
- Does advertising add or replace? If sales without advertising of those same products drop when you turn the campaign on, part of the dashboard's ROAS is sales you would have made anyway.
- How much does advertising weigh on everything you sell? The Mercado Ads API includes the TACOS metric, which the industry uses to relate ad investment to total sales (with and without advertising). If it climbs month over month, you depend more and more on paying to sell.
The other metrics are the standard ones on any platform: impressions, clicks, CTR, CPC, spend, conversion, and impression share.
Bonuses
Mercado Libre offers bonuses for Product Ads with their own rules: for certifying in Ads Academy (with an active Product Ads contract), for joining the launch program for new sellers, for campaigns in specific seasons, and for those the sales team assigns. Check your account for any before you start.
Mercado Ads or your own channel: where each peso works harder
Mercado Ads is the right tool for moving sales within Mercado Libre: the buyer is already there, with purchase intent. What it doesn't do is build your customer base. The sale and the contact stay on the marketplace.
That's why we work the two fronts separately:
- Mercado Ads for products with enough margin and competition for position, with a target ROAS set per margin group.
- Advertising toward your own store (Google and Meta) for products where the sales fee leaves you little margin, and to capture customers who then come back through email or WhatsApp. If you use Google, see how Performance Max campaigns work.
Comparing cost per sale across the two channels, product by product, is the most honest way to decide where to put the next peso.
Conclusion
Mercado Ads works when each campaign has a target ROAS that comes from your real margin, not from intuition. With the break-even formula, the split between direct, indirect, and sales without advertising, and a monthly check on how much advertising weighs on your total, you can tell whether you're buying growth or buying sales at a loss.
At We make it Lab we work with brands that sell on Mercado Libre and want to grow without depending only on the marketplace: advertising inside and outside Mercado Libre, your own store, email, and CRM. If you want us to review your campaigns with your numbers, get in touch.
Sources consulted
