TL;DR
Google's US and GB product taxonomy files are not translations of each other. They are separate categorisation systems with different branches, different names, and different nesting, and using the wrong one silently drains your campaign budget.
You copied your US product feed across to the UK, swapped the currency, and shipped it. Google Merchant Center accepted the feed without complaint. Your UK Shopping campaigns are running, impressions are trickling in, but the click-through rate sits at a fraction of what you see stateside. The problem isn't your bidding strategy or your imagery. It's that your products are sitting in categories that don't exist in the UK taxonomy, or exist with different names, different nesting, and different children.
What you'll take away
- Two distinct files — Google publishes separate en-US and en-GB taxonomy files with hundreds of category differences.
- Wrong taxonomy dilutes bids — mismatched categories weaken ad targeting and reduce impression share in the affected market.
- Platforms read either — Google Merchant Center accepts both, but Meta and TikTok each map categories differently and may reject unmatched entries.
- Audit before launch — running a category diff before going cross-border prevents weeks of silent underperformance.
What the two taxonomy files actually are
Google publishes its product taxonomy as plain-text files, one per locale, and anyone can download them. The US version lives at https://www.google.com/basepages/producttype/taxonomy.en-US.txt and the GB version at https://www.google.com/basepages/producttype/taxonomy.en-GB.txt. Each file is a numbered list of full category paths separated by greater-than signs, and Google Merchant Center uses these paths to understand what each product actually is.
The US file is the larger of the two. It contains over 6,000 taxonomy nodes and reflects the breadth of American retail. The GB file is leaner. It omits entire branches that don't map to UK retail norms, renames others, and restructures the hierarchy in places where the US nesting would be nonsensical for British shoppers.
Where the two taxonomies diverge
The differences fall into three patterns: categories that exist only in the US, categories that exist only in GB, and categories present in both but nested under different parents. The third pattern is the one that catches merchants off guard because the category name looks familiar, so the feed validates, but the semantic meaning has shifted.
| US category path | GB equivalent | What changes |
|---|---|---|
| Health & Beauty | Health & Beauty | Same name, different child categories |
| Apparel | Clothing | Renamed at the top level |
| Pet Supplies > Live Animals | Not present | Branch removed entirely |
| Food items under Grocery | Narrower Food hierarchy | Children reordered and relabelled |
A mismatched category doesn't trigger an error
Google Merchant Center will accept a US category ID in a GB-targeted feed. It won't flag it. The feed passes validation, the products go live, and the only signal you get is a campaign that underperforms.
Why taxonomy choice changes campaign performance
Google uses your google_product_category attribute to match products to shopper queries and to determine which competing ads enter the same auction. When a UK shopper searches for a product, Google's system expects products tagged with GB taxonomy paths. A product carrying a US-only category still enters the auction, but the matching signal is weaker, so your bid has to work harder to win the same impression.
Think of taxonomy as the filing system in a department store. If you file a product in the wrong cabinet, the shop assistant can still find it by reading the label on the box, but it takes longer and the assistant is less confident. Google's auction works the same way. A correct GB taxonomy path is a strong relevance signal that helps your bid go further. A US path in a UK campaign is a weak signal that forces you to overbid for the same placement.
Which platforms accept which taxonomy
Google Merchant Center accepts both the en-US and en-GB taxonomy files, and it maps category IDs rather than names, so a valid numeric ID from either file will populate the google_product_category field without raising a validation error. The platform you choose for your feed matters because each shopping destination has its own approach to category mapping, and some are stricter than others.
| Platform | Accepts en-US taxonomy | Accepts en-GB taxonomy | Notes |
|---|---|---|---|
| Google Merchant Center | Yes | Yes | Uses numeric category IDs from either file |
| Meta Catalog | Mapped | Mapped | Has its own taxonomy. Maps loosely from Google categories. |
| TikTok Shop | Not directly | Not directly | Requires its own category taxonomy, not Google's |
Meta and TikTok do not consume Google's taxonomy natively. If you feed a Google category path to either platform, it attempts a mapping. Unmatched categories fall through to a generic default and lose targeting precision.
How to audit your feed before going cross-border
The fastest way to catch taxonomy mismatches is to download both files and run a diff before you launch in a new market. You are looking for any category path in your current feed that does not have an exact match in the target locale's file.
Cross-border taxonomy audit
- Check top-level names — Apparel in the US is Clothing in GB. If your feed references Apparel, remap it.
- Verify child categories — a parent may exist in both files but contain different children. Check the full path, not just the top level.
- Look for removed branches — categories related to live animals, certain regulated goods, and US-specific seasonal events may not exist in GB.
- Test a sample batch — upload ten products with remapped categories and watch the diagnostics for 48 hours before committing the full feed.
The cost of getting it wrong
A wrong taxonomy doesn't break your feed. That is what makes it dangerous. Google Merchant Center's diagnostics panel flags hard errors like missing GTINs, broken image URLs, and policy violations. It does not flag a US category running in a UK campaign because the category ID is technically valid. The consequence is silent underperformance: lower impression share, higher cost per click, and a campaign that looks healthy on paper but never reaches its potential.
Before · US taxonomy in a UK feed
google_product_category: 1604 (Apparel > Clothing > Shirts & Tops)
After · GB taxonomy, correct path
google_product_category: 1604 (Clothing > Shirts & Tops)
The numeric ID may be the same, but the path string that Google uses for query matching changes. Using the GB file's category path ensures the full text string matches what Google expects for UK shoppers. Always use the path string from the correct locale file, not just the ID.
If you are expanding from the US to the UK or vice versa, block out an afternoon for the taxonomy diff. It is the single highest-ROI task you can do before launch, and it prevents weeks of wondering why a campaign that works at home is underperforming abroad.
Common questions
Does Google Merchant Center reject US categories in a UK feed?
No. Google Merchant Center accepts numeric category IDs from both the en-US and en-GB taxonomy files, so a US category ID will not trigger a validation error. The feed passes, but the mismatch weakens query matching and can reduce impression share in UK campaigns.
Can I use the same google_product_category for US and UK products?
You can, but you shouldn't. The numeric ID may be valid in both files, but the full category path string differs between locales. Using the correct locale's path ensures Google's matching system reads the strongest relevance signal for that market.
How often does Google update the taxonomy files?
Google does not publish a fixed update schedule for the taxonomy files. Changes happen periodically, often to reflect new product categories or retail trends. Download the current files before any cross-border feed launch rather than relying on a cached copy.
Do Meta and TikTok use Google's taxonomy?
No. Meta has its own catalog taxonomy and attempts a loose mapping from Google categories. TikTok Shop requires its own category taxonomy entirely. In both cases, unmatched Google categories fall back to generic defaults and lose targeting precision.
What is the difference between google_product_category and product_type?
The google_product_category attribute must use a path from Google's official taxonomy file. The product_type attribute is a free-text field where you define your own categorisation. Both influence how Google matches products to queries, but only one is governed by the official taxonomy files.
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Editorial note
Written by Muhammad Norafif
This article was published on September 1, 2026 and last updated on September 1, 2026. NextFeed builds product feed management software for Shopify, Google Shopping, Meta, and other commerce channels.