Improve your shopping ads with supplemental feeds and rules

Paid SearchPerformance Media


Google’s shopping feed management can get a little frustrating at times. Issues can include multiple errors on feed download, product names not containing required keywords, products not structured in a logical format… these are just some of the issues that you may face when setting up your feed for the first time. There are tools out there that help with data feed management but most are quite pricey and if you’re only managing a handful of clients, they may not be the best solution. Luckily, Google Merchant Center has supplemental feeds and rules! Combining rules with supplemental feeds can achieve the majority of functions most data feed management platforms provide. 

In this blog, I’ll be sharing a few ideas on how to leverage these two features.

Before we look at any examples, let’s define what a supplemental data feed is. Based on Google’s definition, a supplemental feed is asecondary data source to provide additional attributes to your primary feeds, or to provide additional data that you want to use in Feed Rules.”

How to access supplemental feeds in Merchant Center:

  1. Log into Google Merchant Center 
  2. Click on Products, then Feeds

To get the most out of a supplemental feed, it’s best to create it in a format that’s easily edited. The easiest format we find at Metric Labs is Google Sheets. 

How to create a supplemental feed in Google Sheets:

  1. Log into Google Merchant Center
  2. Navigate to the Feeds section
  3. Click ADD SUPPLEMENTAL FEED and name your feed
  4. Select Google Sheets
  5. Select Generate a new Google spreadsheet from a template or Select an existing Google sheet

Since we want the supplemental feed to be a replica of the original, we need to duplicate the original feed into Google Sheets. 

Most original feeds we work with are in XML format, and the easiest way to transform these to Google Sheets is by using Excel. 

How to upload XML files to Google Sheets:

  1. Open Excel
  2. Go to File > Open > Browse
  3. On the new dialog box, select XML files and paste the data feed URL in the text box

This should open up the XML feed in an Excel format. You can then upload the sheet into the Google Sheet supplemental feed.

After copying the Excel data to Google Sheets, make sure your header row matches the Google Merchant Centre format

Now that we have our supplemental feed in Google Sheets. Here are 3 tips on how to optimise the feed for improved shopping ads.

1. Edit the titles to include relevant keywords

Since Google Shopping uses keywords as a signal for relevance, you want to make sure your product titles include the keywords you want your ads to appear for. The great thing about upplemental feeds is that they allow you to do this without changing the original listing on your site. Changing the original makes the titles on your site appear spammy and detracts your buyers. Using a supplemental feed will only change the titles for the ads, but not the original.

For our fashion clients, we edit titles to include an edited version of the original title appended with the gender, colour, size, category, and brand name. For example, if the original title was “Air Force 1” and the product was for men, the colour was black, and the size was 42, then the new optimised title would be: 

“Black Air Force 1 | Men’s Shoes Size 42 | Nike”

You can experiment with the order of keywords and see what works best. You can also include keywords like “Afterpay” if that helps to generate more traffic and revenue. These changes can easily be done using the CONCATENATE function on Google Sheets. Once you have made all relevant changes to the titles, it’s time to set the rules for the feed. 

How to set rules for the feed: 

  1. Click on the original feed in Merchant Center
  2. Navigate to FEED RULES
  3. Click CREATE RULE
  4. Select Processed attributes
  5. And since we’re making a rule for the title, select title

6. Select Set to (this will assign the new title from the supplemental feed) and click OK 


Once you have done this, you should see the new title published on the right panel. You can then save as Draft and then test the changes before applying. 

Protip: Remember to change the default rule for other attributes to always take from the original feed.  

2. Add missing GTINS using the identifier_exists variable via a supplemental feed

This next tip is if we are assuming you have uploaded your original feed and get errors because your products don’t have GTINs or MPNs. This is common mistake with feeds that contain a mixture of custom and ‘standard’ commercial products. 

To fix these errors, the first thing you need to do is download the error reports and identify which items don’t have GTINs. Then, create a supplemental feed as we did above. Once the supplemental feed is created add an additional column with the title identifier_exists”. The identifier_exists attribute helps to indicate that the GTIN, MPN or brand attributes aren’t available.

Now, for every product without a GTIN enter FALSE in the identifier_exists column, and for every product with a GTIN enter TRUE. 


Now, let’s create a rule instructing Google to look at the supplemental feed when assessing the identifier_exists field: 

  1. Go to the original feed and navigate to the FEED RULES tab
  2. Select create feed then choose identifier exists
  3. Select set to {{supplemental feed name}} identifier exists
  4.  Then click OK, Save as draft, and run the test

3. Add custom labels to supplemental feeds

If you are looking to get more granular with your shopping ads campaign or ad group segmentation, then using custom labels on a supplemental feed might be the trick. You can use custom labels to split products based on any customer groupings you like. 

Here are two examples where you may need custom labels: 

  1. You are a fashion brand and want to split your products by season or collection
  2. You want to categorise your products based on sales propensity e.g. labelling the best sellers and loss leaders

To add custom labels, create a new column labeled custom_label_0 and enter the relevant label


Closing thoughts

I hope the tips above give you a better understanding on how to use supplemental feeds and rules. The two in combination are powerful in optimising shopping feeds and improving campaign performance.

If you have used these two features in a different way, then please feel free to share your ideas in the comments. 


Like this blog post? Sign up to our email newsletter – Lab Report – and never miss a new one. Or, get it sent straight to your Messenger

Reminder: Google UA Historical Data to be Deleted in July 2024