Google Shopping Feed Optimisation: Titles, Attributes and Merchant Center Fixes That Lift ROAS

Google does not read your product pages when deciding which searches to show your ads on. It reads your feed. A store with excellent products and a lazy feed will lose impression share to a worse store with a better feed, every day, at any budget. Feed work is the least glamorous and most reliably profitable task in paid search. Here is the order we do it in.

Titles: the 80/20

Shopify sends your product title as the feed title. "The Original" or "Lavender" is a name, not a search query. Google matches heavily on the first 70 characters of the title, so rewrite them in the feed (not necessarily on site) using a category-specific formula:

Put the searched-for term first for generic categories, the brand first where brand carries the query. Use a feed tool (Simprosys, DataFeedWatch, or Shopify's own Google & YouTube app with rules) so on-site titles stay clean.

Identifiers: GTIN, MPN, brand

• GTIN (barcode) on every product that has one. Products with GTINs get matched to Google's product catalogue, which unlocks richer listings and better query matching. Missing GTINs on branded goods leads to limited performance or disapproval.
• Own-brand products without barcodes: set identifier_exists = false and supply brand + MPN. Do not invent GTINs — Google validates them.
• Brand attribute should be the manufacturer, not your store name, for resold products.

Attributes that expand matching

• google_product_category — the most specific node available. "Home & Garden > Household Supplies > Household Cleaning Supplies > All-Purpose Cleaners" not "Home & Garden".
• product_type — your own taxonomy, mirroring your collection structure. Useful for campaign segmentation.
• color, size, material, pattern, age_group, gender — mandatory for apparel, valuable everywhere. They feed filters in Shopping and free listings.
• description — first 500 characters matter. Replace supplier boilerplate with what the product is, who it is for, and key specs.
• Additional images — lifestyle plus plain background. Google increasingly tests image variants.
• shipping and tax — configure in Merchant Center, not per product, and keep them consistent with the site or you will get price/shipping mismatch disapprovals.

Custom labels: how to segment campaigns

Five custom_label fields let you group products for bidding. The ones that earn their keep:

1. Margin band (high / mid / low) — bid harder on what makes money.
2. Performance tier (hero / steady / long-tail / zero-sales) — refreshed monthly from Shopify data.
3. Price bucket (<£20, £20–50, £50–100, £100+).
4. Seasonality (BFCM, Christmas, summer).
5. Stock depth (deep / limited / clearance).

These labels become the asset groups or listing groups in Performance Max — see the structure in our PMax guide.

Merchant Center hygiene

• Disapprovals. Check weekly. Common UK ones: price mismatch (sale pricing not synced), missing shipping for a country, "misrepresentation" (usually missing returns/contact info on site), and image issues (text overlays, watermarks).
• Sale price annotations. Use sale_price and sale_price_effective_date so Google shows the strikethrough — a visible CTR lift during promotions.
• Price competitiveness and best-sellers reports in Merchant Center tell you where you are being outpriced and which products have category demand you are missing.
• Feed refresh frequency. Shopify's app syncs continuously; third-party feeds should update at least every 6 hours for stock-sensitive catalogues.
• Supplemental feeds let you overwrite titles, add custom labels or fix categories without touching the primary feed — the safest way to iterate.

Free listings and the Shopping tab

Everything above also improves your free listings in the Shopping tab and image search. For UK stores this is typically 5–15% of organic e-commerce traffic that most people never look at. Make sure "free listings" is enabled in Merchant Center and that products have the same attribute quality as your paid feed — it is the same feed.

Testing feed changes

Change one thing at a time on a subset (via supplemental feed on one custom label), wait 14 days, compare impressions, CTR and conversion rate for that group against the control. Title changes typically show within a week; category and attribute changes take longer as Google re-classifies.

If your Shopping impression share is under 30% on your own category terms, the feed is the problem before the bid is.

Frequently asked questions

What is the most important attribute in a Google Shopping feed?

The title. Google matches primarily on the first ~70 characters, so titles should lead with the terms customers search (brand, product type, key attribute, size). Followed by GTIN and google_product_category.

Do I need GTINs for Google Shopping?

For branded products that have barcodes, yes — missing GTINs limit performance and can trigger disapprovals. For own-brand products without barcodes, set identifier_exists to false and provide brand and MPN.

How do I optimise my Shopify feed without changing product titles on my site?

Use a feed management app (Shopify's Google & YouTube app with rules, Simprosys, or DataFeedWatch) or a Merchant Center supplemental feed to override titles, categories and custom labels in the feed only.

What are custom labels used for?

Segmenting products into groups for bidding and reporting in Shopping and Performance Max — for example by margin band, best-seller status, price bucket or seasonality.