Google Merchant Center

How to use Supplemental Feeds in Google Merchant Center

2 · by Dennis Moons · Updated on 30 September 2022

Sometimes you want to make small tweaks to your product information in Google Merchant Center.

But it’s not always clear how or where to make those changes.

Supplemental feeds offer an unrivaled level of flexibility to make these types of changes.

So in this article, we’ll go into detail about how supplemental feeds work in Google Merchant Center, and when and where to use them!

What are Supplemental Feeds in Google Merchant Center?

As its name says, a supplemental feed is a file that supplements or adds data to your primary product feed.

That means a supplemental feed can only be used to update products that already are in Google Merchant Center (GMC), you can’t use it to add new products with this method.

The most common reason to use them is to add information that can improve the performance of your Google Shopping campaigns.

For example. Let’s say you have a product in GMC that’s titled “Brown Handbag”.

You can use a supplemental feed to change that title, add some extra keywords and transform that title into: “Brown Leather Handmade Handbag”.

Supplemental Feeds vs. Primary Feeds

What exactly is the difference between supplemental feeds and primary feeds? Well, here’s a brief explanation.

 Primary feedSupplemental feed
Connects to your ecommerce platformyesno
Can add products to GMCyesno
FormatAll required fields according to product data specificationOnly the product id is required

Supplemental Feeds vs Product inventory Feeds vs Promotions Feeds

There are a few different types of feeds that you can add to Google Merchant Center that interact with the main feed.

So to clear up some confusion, I want to show the differences:

  • Supplemental feed: to add or edit information from the main feed
  • Product inventory feed: this allows you to update the inventory that you have available in physical locations
  • Promotions feed: this allows you to specify the details of a Merchant Promotion

How To Use a Supplemental Feed

One of the most common use cases for supplemental feeds is to optimize product titles.

So let me show you how supplemental feeds work through an example.

This is what your primary feed looks like:

1Brown shoes150
2Brown sandals50
3White trainers200

These product titles look a little basic and generic. So to improve them, I want to add more detail to them. That will help them to show up for the right search queries, which will improve our chances of getting clicks and sales.

To do that, I’m going to create a supplemental feed with the updated product titles.

An important part is that I need to include the id of the products I want to update, as that is how Google “merges” the information from both feeds.

Supplemental feed:

1Vegan brown leather dress shoes
3Men’s white snakeskin trainers for running

The product feed will be updated accordingly for the specified ids. The other products will be unchanged.

“Final feed” feed:

1Vegan brown leather dress shoes150
2Brown sandals50
3Men’s white snakeskin trainers for running200

The Main Benefits of Using Supplemental Feeds

Here are the main benefits of using Supplemental feeds to optimize your product information inside of Google Merchant Center.

Save Time

Making individual changes to your primary feed can be very time-consuming. With supplemental feeds, you’re able to make bulk changes to the feed.

This will save you a ton of time.


Supplemental feeds offer far more flexibility to change your product data compared to other methods like feed rules.

When to Use Supplemental Feeds?

The most common reason for advertisers to use supplemental feeds is that they want to add information that’s not yet available in the feed.

Optimizing Product titles

When it come optimizing product titles, there are 2 types of changes that you can make.

Using information from within the feed. For example: you add the brand in front of the title. This is a change that will be much easier to do using feed rules.

But if you want to rewrite every single title, a supplemental feed gives you the ease of use of a Google sheets to make those edits.

Adding Product identifiers

When you’re dealing with product disapprovals because of incorrect product identifiers (GTINs, MPNs, etc.), you can use a supplemental feed to add these to your feed;

Ideally you want this information to be available in your ecommerce platform. But if that’s not possible for some reason, you can add it this way.

How to Create a Supplemental Feed in Google Merchant Center

Creating a supplemental feed is pretty easy.

First, log in to your Google Merchant Center account.

Step 1 – Navigate to the Feed overview

Click Products in the left hand menu, then click Feeds.

Adding a supplemental feed

This will show you an overview of all the feeds associated with this GMC account.

On the bottom half of the page, you will see the Supplemental feeds section.

There, click “Add supplemental feed”.

How to add a supplemental feed in Google Merchant Center

Step 2 – Add a name for the supplemental feed

First, add a name for your feed. Make sure it’s descriptive of which feed you want to update, and what attributed you’re planning on changes.

For example: APES-US-TITLES

This is the supplemental feed for APES-US (my primary feed targeting the USA) where I’m adding optimized product titles.

Step 3 – Choose the input method

Similar to the primary feed, there are a few ways to add supplemental feeds.

The most important, and easiest to use input method, is Google Sheets.

Other methods are a file upload or the Content API.

Step 4 – Link to Primary feed

Recall that a supplemental feed cannot work alone. So in this section, choose the primary feed and country of sale to which you supplemental feed will be applied to.

Then, click the “Create feed” button to create your supplemental feed.

Step 5 – Fetch the new feed

After you create your supplemental feed, you’ll want to “fetch” it. That means Google Merchant Center will look at the file you just created, and it will try to match it with the product ids of the main feed.

fetch supplemental feed google merchant center

This process will also tell you if worked or not.

How to Remove a Supplemental Feed

Removing a supplemental feed is a little tricker than you might think at first.

Step 1 – Delete The Feed Rule Connecting Your Supplemental and Primary Feed

When you add a supplemental feed, Google Merchant Center automatically creates a Feed Rule to add the data into your primary feed.

So before you can delete the supplemental feed, you first need to delete that rule.

Here is how you do that:

  1. Go to Products > Feeds, and then click on the primary feed who’s supplemental feed you want to remove.
  2. Click on the “Feed rules” tab
  3. Hover over the rule you want to delete and click the trash icon
  4. Click “Apply” to update the rules (important!)

Once that’s done, it’s time to find the supplemental feed you want to remove and delete it.

Step 2 – Deleting a Supplemental Feed

Now you should be able to delete the supplemental feed.

  1. Identify the feed you want to delete.
  2. Hover your mouse pointer over its name and click the trash icon to delete it
How to remove a supplemental feed in Google Merchant Center

Using Supplemental Feeds to Maximize Shopping Success

Optimizing your product feed is a strategy that’s becoming ever more important in the world of Google Shopping.

And while you can change or edit product data in a lot of different ways, supplemental feeds are the most flexible option.

Dennis Moons

Dennis Moons is the founder and lead instructor at Store Growers.

He's a Google Ads expert with over 12 years of experience in running Google Ads campaigns.

During this time he has managed more than $5 million in ad spend and worked with clients ranging from small businesses to global brands. His goal is to provide advice that allows you to compete effectively in Google Ads.

Follow him on Twitter or LinkedIn.


2 responses on "How to use Supplemental Feeds in Google Merchant Center"

  1. Hi Dennis,

    I have been selling luxury designer items online previously using the Facebook/Instagram App, and trying to get started with the Google Channel App too.

    Whilst editing my feed within ‘manage products’ in the Google Channel App, the ‘Vendor’ column is listed as my brand name rather than the product brand designer names. Shopify states that the Vendor is: ‘The manufacturer, wholesaler, or other vendor for the product’ of which I am the ‘other vendor’ and obviously not the manufacturer hence why this has been done.

    The Google Channel requires GTIN/Brand attributes but there is no ‘Brand’ column… and therefore I have amended the ‘vendor’ to reflect the brand names of the actual products which caused all my products on the Facebook/Instagram App to become disapproved; the Facebook/IG app stated they do not accept the product brand names being used due to trademarks/copyright issues which makes total sense and therefore I changed this ‘vendor’ column back to my brand name and alas all was fine again.

    Therefore I am left abit puzzled as to where I can submit ‘BRAND’ information about my products – I am assuming obviously the GTIN/MPN etc obviously goes in the ‘BARCODE’ column, however for ‘BRAND’ I am abit lost as to where this go to allow me to show products across both channels. Here are my possible solutions :

    1. Leave as normal and to try run products on Google Shopping with the ‘demoted due to missing GTIN/BRAND’ product error. Is this likely to trigger a Merchant Centre Suspension due to possible misrepresentation, since the brand is obviously showing as my brand name rather than the actual product brand name – the items have been approved however already in GMC having an ‘active’ status?!

    2. Would a Supplemental feed be of use here within GMC to introduce the Brand/GTIN etc columns? I would be really keen to hear how using a GMC supplemental feed may interact with using the Content API (Google Channel and whether its actually wise to use both along side each other?

    3. Scrap the Google Channel and upload a feed through Gsheets etc – obviously alot more long winded and requires ongoing maintenance with price changes etc that woudlve been automated by the Content API (Google Channel) but would of course allow separate and full control of the feed columns without interfering with the Facebook/IG channel. Ideally I want to keep the Content API (Google Channel) as I like the integration and prefer to keep everything centralised – I am however open to flexibility to finding the right solution of course!

    Thankyou for taking the time to read the above.

    1. Dennis Moons says:

      Hi Benjamin,
      I highly recommend keeping using the Google channel/Content API which keep all of your data updated inside of GMC.

      But for the brand field, you want to add a fix inside of GMC that will change the data that are coming through from Shopify.

      There are 2 possible fixes for your problem:

      1. supplemental feed: make a list of all your products with the ids in column 1 and the correct brand in column 2. (This will work but the downside is that new items won’t be added automatically to the list)
      2. feed rules: if you can come up with rules to make the vendor field map to the brand, you can set up feed rules to automatically do this for all items in your feed (check this article for more info)

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