How to increase ROAS: a guide for e-commerce

What is ROAS, and how is it calculated?

ROAS (return on ad spend) is the ratio of revenue generated by advertising to advertising spend. The calculation is simple: you divide the sales revenue attributed to ads in a given period by the ad spend in the same period. The result shows how many units of revenue each unit of budget spent brought in.

ROAS is the most widely used indicator in e-commerce, because ad platforms report it directly and the bid strategies of Google Ads and Meta can take it as a target. But its simplicity is also its weak point: revenue and profit are not the same thing. In addition, each platform calculates ROAS with its own attribution window and model; Google Ads, Meta and GA4 can show different results for the same period. When comparing periods, keep the source and attribution setting you use constant.

What is the difference between ROAS and profitability?

ROAS measures revenue; it does not account for product cost, shipping, payment fees, returns or discounts. A campaign selling low-margin products may report a high ROAS while losing money, while for high-margin products a lower ROAS may be profitable.

That is why the following concepts matter. Contribution margin is the amount left from an order's revenue after variable costs such as product cost, shipping, fees and returns are deducted. POAS (profit on ad spend) is ROAS calculated with contribution margin instead of revenue. Setting your target as POAS, or at least as ROAS targets that vary by product group, steers the algorithm towards profit rather than turnover. We cover the budget scaling side of this in our article on ROI-focused performance marketing.

Is your measurement accurate?

Before trying to increase ROAS, make sure you are measuring it correctly. Duplicate orders, a purchase event that fires incompletely or returned orders not being deducted from revenue make the report look better or worse than reality. A bid strategy fed with wrong data also makes wrong decisions.

• Regularly compare purchase revenue in GA4 with the actual orders in your e-commerce platform.
• Set up Meta Pixel together with the Conversions API, and the Google Ads tag together with enhanced conversions.
• Configure Google's consent mode for measurement that respects cookie consent.
• Instead of adding up the sales each platform reports, compare them with total sales; each platform counts its contribution by its own rules.
• Report sales from brand searches separately from new customer acquisition.

How does campaign structure affect ROAS?

Splitting the account into lots of small campaigns makes it harder for each campaign to collect the conversion data the algorithm needs to learn. On the other hand, putting everything into a single campaign leads to profitable and unprofitable products being managed with the same target. A balanced structure usually splits products into margin and performance groups, keeps brand searches separate, and manages new customer acquisition and remarketing with different targets. If you use Performance Max, build asset groups and product groups on this logic and review search term and placement reports regularly.

How do you improve the product feed and catalogue?

In Shopping ads, Performance Max campaigns and Meta's catalogue ads, the ad itself is generated from the product feed. The quality of the feed determines both which searches you appear for and how likely people are to click.

Put the terms people actually search for (brand, product type, material, colour, size and so on) at the front of product titles. Make sure images are clear and comply with platform rules, and that price and stock information match the site exactly. Monitor warnings and disapproved products in Merchant Center regularly. Grouping products with custom labels such as margin, sales velocity and season is a prerequisite for separating budgets and targets by product group.

How does creative affect ROAS?

As targeting becomes increasingly automated, what gets the ad to the right person is largely the creative itself. Videos showing the product in use, benefit-led messages and user-generated-style visuals perform differently across audiences. Produce creatives from hypotheses, judge their results on sales and profit rather than click-through rate, and refresh fatigued creatives regularly. Formats such as Advantage+ campaigns on Meta and Spark Ads on TikTok work better in accounts with high creative variety.

How should audiences and remarketing be structured?

Remarketing is usually the campaign that reports the highest ROAS, because it is shown to people who are already close to buying. That does not mean its budget should be increased without limit. A significant share of these people may buy even without seeing an ad. Separate remarketing audiences by intent, such as cart abandoners, product viewers and past customers, and cap how often they see ads.

Giving platforms your existing customer lists and high-value customers as signals helps the algorithm find similar buyers. Tracking new customer acquisition as a separate goal shows whether the account is only selling to people who already know you.

Why do landing pages and CRO matter so much?

Ads bring the click, but the sale happens on the site. Slow product pages, checkout steps that are hard to use on mobile, surprise shipping costs and a lack of trust signals all mean fewer sales for the same ad spend. Every improvement in conversion rate raises ROAS without changing a single setting in the ad account. We explain the method behind this work on our CRO and analytics service page.

ROAS is not only about advertising but also about the offer itself. Price relative to competitors, the free shipping threshold, return terms and bundle offers directly affect how likely the same click is to turn into a sale. Complementary product recommendations that grow the basket also raise revenue per order and feed through to ROAS.

How should the budget be allocated?

Make budget decisions not on average ROAS, but on the additional result each extra unit of budget brings. Even if a campaign's average looks good, if the budget added to it brings increasingly expensive sales, that budget may be more efficient elsewhere. Feed profitable product groups and campaigns that bring new customers with sufficient budget. Increase budgets gradually so as not to disrupt the algorithm's learning, and set aside a small part of the total budget for new audience and creative experiments.

How does seasonality affect ROAS?

Sale periods, holidays and special shopping days increase both demand and competition. Cost per click rises in these periods, and conversion rate usually rises too. Stock, shipping capacity and the discount plan should be prepared together with the advertising calendar, and creatives and audiences should be ready before the period begins. Tools such as seasonality adjustments in Google Ads let you tell the bid strategy in advance about short-term conversion rate changes. It is natural for ROAS to fall once the period ends; this should not be read as a campaign failure.

Common mistakes when trying to increase ROAS

• Setting the same ROAS target for all products and ignoring margin differences.
• Stopping new customer acquisition to push ROAS up and leaning only on brand and remarketing campaigns.
• Raising the target ROAS sharply and abruptly, cutting the campaign's volume.
• Reading reports without deducting returns and cancellations from revenue.
• Failing to notice feed errors and disapproved products for a long time.
• Looking for the problem only in the ad account without examining price, stock and site experience.

We describe our profit-focused account management approach on our performance marketing service page, and the Shopping and Performance Max side on our Google platform page. For a profit-focused review of your account, get in touch via our contact page.