What is a supplemental feed, and why do I need one?

A supplemental feed runs alongside your primary feed. The goal of your supplemental feed is to enrich the primary feed with more data: it cannot be used without the primary feed. 

How can I use a supplemental feed?

  • To add or modify product information, global trade item numbers (GTINs), promotions, materials, specific attributes, cost of goods sold (COGS), etc. to enrich your primary feed further.
  • To fix errors in the Merchant Centre, and resolve disapprovals on your primary feed.

For more information on GTINs and finding the most suitable universal product identifiers in this handy guide.

How to set up a supplemental feed

1. In Google’s Merchant Centre, click “Products” on the left-hand menu, and then “Feeds”.

The next page displays an overview of your primary feeds and supplemental feeds. How do they differ? Your primary feed is the back-bone of products, pulling your catalogue of products directly from your website to the Merchant Centre.

The supplement feed is used to change, enrich or modify attributes in your primary feed.

Supplemental feed guide step 1

From the above page, start by clicking “Add Supplemental Feed”.

2. Next, you need to name the supplemental feed, choose the relevant “Google Sheet”, and click “Continue”.

New supplemental feed image 2

Here, you can generate a new spreadsheet, or use one you already created.

blur shadow 1

When creating your supplemental feed (in Excel, Google Sheets, etc.), it’s critical that the product ID in the supplemental feed is identical to the product ID in the primary feed. Additional attributes (such as COGS, title, price, custom labels etc.) are linked to the item ID.

example supplemental feed sheet

3. The first time you upload the supplemental feed, you must press “Fetch Now” to apply it to the primary feed.

Setting up supplemental feed step 3

Supplemental feed set up fetch feed

From there, you can adjust how often the supplemental feed is fetched using the “Fetch schedule” drop-down menu under “Settings”.

Do bear in mind that if you use a content API, you may not see an update for 10-30 minutes.

Got any other Merchant Center woes? Check out helpful guides such as 'How to add a feed rule', or 'How to exclude destinations.' For any other FAQs, helpful guides or Google Shopping news, check out our resources.

Are your conversion rates meeting the industry standard? Find out in Bidnamic's Guide to Conversion Rate Optimisation.

Anything else? Our Shopping specialists are always on hand to lend an ear and consult on Google Shopping - book your consultation here.

Harrie-Anna Wormald

Harrie-Anna Wormald

Previously a Google Shopping Specialist, Harrie-Anna now coordinates our Customer Success team in helping clients to understand our technology, how their account is performing, and providing advice for client-side optimisations. She also manages Bidnamic’s onboarding process and our employee book club.