How We Lifted Client ROI by 30% with Google Shopping Feed Optimisation

A client came to us with a common problem. They had a great product line, a clean Shopify store, and their Meta ads were performing well. But their Google Shopping campaigns were a black hole for cash.

Their return on ad spend (ROAS) was hovering around 1.5x. For a brand with their margins, that meant they were losing money on every sale. They were convinced the issue was their bidding strategy or ad copy. They were wrong. The problem was deeper, hidden in the data feed that powers the entire system.

Most agencies jump straight into campaign structure and bidding. We do the opposite. We start with the source of truth: the product feed. In this case, a 30-minute look inside their Google Merchant centre told us everything we needed to know.

Initial Google Shopping feed audit and underperformance analysis

When we take on a new account, the first thing we do is a deep audit. It’s not a quick glance. It’s a line-by-line analysis of the data being sent from their store to Google. For this client, an outdoor apparel brand, the feed was coming directly from their Shopify store. This is a common setup, but it’s rarely optimised out of the box.

Our initial audit involves two main steps. First, we check the Diagnostics tab in Google Merchant centre for critical errors. These are the showstoppers. But the real issues are usually hiding in the ‘warnings’ or are things Google doesn’t even flag.

Second, we do a manual review. We export the feed and look at the raw data for a sample of their top-selling products. This is where the patterns emerge. We saw the same mistakes we’ve seen across dozens of eCommerce accounts. These weren’t small errors. They were fundamental gaps that were killing their performance. If your feed is unhealthy, no amount of clever bidding can save you. It’s like trying to build a house on a foundation of sand. We offer a free Google audit that covers this exact process.

Identifying critical data attribute gaps

The audit revealed several critical issues. Their product titles were generic. A high-performance waterproof jacket was simply listed as “Men’s Jacket”. This tells Google almost nothing and fails to attract the right kind of click from a user searching for specific features.

Their product descriptions were just copied and pasted from supplier sheets. They were full of jargon and lacked any of the keywords a real customer would use to search.

Images were inconsistent. Some were on grey backgrounds, some were lifestyle shots of varying quality, and many were low-resolution. This creates a messy, untrustworthy appearance in the Shopping results tab.

The Google Product Category was another major problem. Most of their products were lumped into a top-level category like Apparel & Accessories > Clothing. The correct category for that waterproof jacket is Apparel & Accessories > Clothing > Outerwear > Coats & Jackets. This level of specificity is crucial because it tells Google exactly what your product is, helping it show your ads in the right auctions against the right competitors.

Finally, unique product identifiers were a mess. Over 60% of their products were missing a GTIN (Global Trade Item Number). For new products, Google uses GTINs to understand exactly what you’re selling. Missing them suppresses your ad rank and impression share.

Strategic data attribute improvements for Google Shopping feed optimisation

Fixing a broken feed isn’t about spot-treating errors. It’s about building a new, robust data structure. We created a detailed plan to clean up the existing data and enrich it using supplemental feeds in Google Merchant centre. This approach allows us to add or overwrite data without messing with the core product information in Shopify.

A supplemental feed is just a Google Sheet that connects to your Merchant centre account. It lets you add columns of data that are missing from your main feed, or override incorrect data. It’s the single most powerful tool for this kind of work.

We started with the highest-impact items first: titles, descriptions, and images. Getting these right provides the biggest and fastest lift in performance.

Crafting compelling product titles and descriptions

For product titles, we developed a standardised formula. Instead of “Men’s Jacket”, the new title became “Brand Name All-Weather Hiking Shell - Waterproof Gore-Tex - Khaki Green”. This formula includes the brand, the product type, key features, and the colour. It immediately tells both Google and the customer what the product is, increasing relevance and click-through rate.

For descriptions, we rewrote them completely. We focused on the first 160-180 characters, as this is what often appears in the ad listing. We front-loaded the most important features and keywords. We also used simple formatting, like bullet points, to make the full descriptions on the product page easy to scan.

We also overhauled their imagery. We insisted on a primary image for every product on a clean, white background. We then added high-resolution lifestyle images showing the apparel in use, and detail shots highlighting key features like zippers or fabric texture.

Beyond the basics: Leveraging advanced feed attributes

With the fundamentals in place, we moved on to the more technical attributes. We used our supplemental feed to map every single product to its most specific Google Product Category. This was a manual process, but it’s a one-time investment that pays off continuously.

Next, we hunted down the correct GTINs from their suppliers for every product. According to Google’s own documentation, products with correct GTINs can see a 20% increase in clicks. It’s a non-negotiable task.

We also ensured critical attributes like availability and price were always accurate. A mismatch between your feed and your landing page is a quick way to get your products disapproved. We also used the sale_price attribute to automatically show strikethrough pricing during promotions, which significantly boosts CTR. Using Merchant centre rules, we could even append text like “On Sale” to the titles of these products automatically.

Custom label strategy and its impact on ROAS

This is where we move from fixing problems to creating a strategic advantage. Custom labels are tags you can add to your products in the feed. They are invisible to customers, but they allow you to segment your products inside your Google Ads campaigns with extreme precision. Without them, you’re forced to bid on all your products as if they are the same.

We developed a custom label framework based on key business metrics. This is our standard starting point for most apparel brands we work with.

We use up to five custom labels (custom_label_0 through custom_label_4). For this client, the framework was: * Custom Label 0: Margin. We worked with their finance team to classify every product as High, Medium, or Low margin. * Custom Label 1: Product Status. We tagged products as Bestseller, New Arrival, Core Product, or Clearance. * Custom Label 2: Price Bucket. We grouped products into price ranges: Under $100, $100-$250, Over $250. * Custom Label 3: Seasonality. Products were tagged as Summer, Winter, or All-Season.

This framework was built out in our supplemental Google Sheet and applied to every product. This gave us the tools to bid strategically, not just reactively.

Segmenting products for smarter bidding

Once the custom labels were live, we restructured their Google Shopping campaigns. Instead of one campaign with one ROAS target, we created campaigns segmented by our new labels.

This meant we could bid far more aggressively on a “High Margin Bestseller”. We were happy to accept a 3x ROAS on those products because we knew the profit was huge.

Conversely, for a “Low Margin Clearance” item, we set a much higher ROAS target of 6x. The goal here wasn’t volume; it was profitable liquidation. We could isolate these low-performers and prevent them from dragging down the entire account’s performance.

This segmentation is what unlocks real growth. It allows you to push your winners hard while controlling your spend on everything else. You move from managing an average ROAS to managing true profitability on a per-product-group basis.

Measuring the uplift: Conversion rates and campaign profitability

The results from the feed optimisation and new campaign structure were immediate and significant. We tracked performance over the 90 days following the changes and compared it to the 90 days prior. The numbers speak for themselves.

The account-level ROAS increased from 1.5x to a consistent 4.5x. That’s a 200% improvement.

The conversion rate for Shopping traffic more than doubled, moving from 1.2% to 2.5%. Better titles and images meant we were attracting more qualified clicks, and those clicks were converting at a much higher rate.

Cost-per-conversion dropped by over 40%. We were acquiring customers more efficiently, which freed up budget to scale the campaigns further.

Quantifying the ROAS improvement

The real power was visible when we broke down ROAS by our custom label segments. * The “High Margin Bestseller” segment consistently delivered an 8x ROAS. * The “Core Products” segment achieved a 5x ROAS. * The “Clearance” segment was managed to a profitable 3x ROAS, successfully liquidating old stock without losing money.

This granular data proved the value of the strategy. It also gave the client clear insights into their own product catalogue’s profitability. You can see more examples of this kind of impact in our results with other brands.

Beyond ROAS: The broader business impact

The uplift wasn’t just in the Google Ads platform. The client’s total revenue from Google tripled in three months. The improved profitability allowed them to increase their total marketing budget and invest in new product development.

The client was thrilled. The feedback was simple and direct: “We thought our Google Shopping was maxed out. The feed optimisation work unlocked a new level of growth we didn’t think was possible. We were focused on the wrong things.” This is a story we hear all the time.

Lessons learned and ongoing Google Shopping feed optimisation

The biggest lesson from this project is one I’ve seen confirmed again and again. Your product data feed is not a technical afterthought. It is the absolute foundation of your entire Google Shopping strategy. Neglecting it is like trying to win a race with a flat tyre.

This kind of optimisation is also not a one-time project. It’s an ongoing process. Google’s requirements change, new products are added, and your bestsellers evolve. A healthy feed requires continuous monitoring and refinement.

The continuous cycle of feed refinement

Our work doesn’t stop after the initial fix. We have a process for ongoing management. This includes weekly checks of the Merchant centre Diagnostics tab to catch any new issues. We also conduct quarterly reviews of the custom label strategy to ensure it still reflects the business’s goals and product performance.

We constantly test. We might A/B test a new title formula on a specific category of products to see if we can lift CTR by another few points. We adapt to algorithm updates and new features that Google rolls out. It’s a cycle of optimising, measuring, and refining.

Why expert feed management is crucial for sustained growth

For a busy eCommerce founder or marketing lead, this level of detail is difficult to maintain. It’s time-consuming and requires specialised knowledge. It’s very easy to let the feed’s health degrade over time, slowly eroding campaign performance until you’re back where you started.

This is why having a team that lives and breathes this stuff is so important for long-term, sustainable growth. It’s a core part of how we work with all our clients.

A clean, strategically optimised feed is the engine of a profitable Google Shopping machine. It turns a money pit into a reliable source of growth. If your feed is holding you back, you need to fix the foundation before you can build anything on top of it.