How to Use Google's Automated Discounts on a Shopify Store (and the Cart Data They Need)

TL;DR

Google's automated discounts drop a product's price for shoppers who click your Shopping ads [4], and on Shopify they run through the Google & YouTube app, built by Google LLC [11]. Google sets those prices from purchase conversions that include cart data: which products sold, at what price, in which quantity [3][8]. If you also send purchases server-side and bid on that upload, it can't feed the pricing, because it carries no items. So the channel's purchase has to keep measuring beside your upload. Google's pages don't settle whether it can do that job as a secondary action [3][9], which leaves two workable setups.

Key Takeaways

• The setup path is Settings > Automations > Automated Discounts inside the Google & YouTube app, with Product sync automatic and Conversion measurement On [1].
• Google prices from Primary conversions with cart data, otherwise from the Purchase conversion that has carried the most carts [3], yet its cart-data setup steps say to set the Purchase conversion to Primary [9]. Whether a secondary channel action is enough is unsettled.
• WeltPixel Conversion Tracking's Google Ads upload sends the order total, currency, order ID, click IDs and (with Enhanced Conversions on) hashed customer data. It sends no line items and configures nothing in Merchant Center.
• The channel's Remove control, or setting its purchase to "Don't measure in linked account", takes the cart data away along with the channel's measurement [13].
• Google shows optimized prices to 10% of visitors for the first 3 days, then 90%, and holds the remaining 10% out as a control [5].
• Every destination the app sends to receives the discounted order total, because the Google price reaches checkout as a Shopify discount code [1].
• Check Goals > Diagnostics in Google Ads for cart-data problems; allow 24 to 48 hours after a fix [7][12].

Which half of your tracking supplies the cart data?

The channel's. A Shopify store running both the Google & YouTube app and a server-side tracking app has two purchase sources pointing at the same Google Ads account, and only one of them can describe the cart.

Google's cart-data page defines the requirement plainly. Conversions with cart data "provide the details of products sold for each transaction", only items from a Merchant Center account linked to Google Ads are processed, and "Item IDs passed in the items array of your conversion tag must exactly match the id attribute in your Merchant Center feed" [8]. The automated discounts setup adds a Purchase event, a price value and a cart total above the cost of goods [3].

Here is that list against what the app actually uploads:

The app also fires no browser-side Google Ads conversion. Its storefront code only gathers click IDs and consent state for the server upload. So on this setup, every cart Google can read arrives through the channel's measurement, which Google's Shopify setup requires to be On [1].

Google also accepts cart data through Google Analytics ecommerce tracking [9]. We haven't verified that the app's server-sent GA4 purchases would qualify, so don't plan a setup around it.

Setting it up through the Google & YouTube app

Google's Merchant Center page lists the Google & YouTube app for Shopify [2], and its Shopify-specific page gives the steps [1]. We found no Shopify Help Center article on the feature. The Shopify-side evidence is the App Store listing itself, where Google LLC describes the app with "Let Google AI handle sale pricing. Optimize profits with Automated Discounts." [11]

1. Install the Google & YouTube app from the Shopify App Store [11].
2. In the app, go to Settings > Automations > Automated Discounts [1].
3. Confirm Product sync is automatic and Conversion measurement is set to On [1].
4. Grant the app permission to write discounts. Google's wording: "you would have to provide Google with the access to write back the new auto-generated discount codes to Shopify discounts… to reflect the discounted price to the end consumer" [1].
5. In the theme editor, add the Automated Discounts Price Block to each product page template. It's an app block that shows the Google price as a strikethrough [1].
6. Set the account-level Gross Profit Margin percentage and Maximum Discount percentage, then add product-level Cost or Minimum Price overrides where a product needs its own cost or price floor [1].

Two details from the same page are easy to miss. Outside the US and Canada, "include VAT in the Cost attribute, if applicable" [1]. And "Automated discounts doesn't support conversions in Floodlight or Search Ads 360" [1].

Google's Shopify page states no Shopify plan requirement, no country list and no review timeline. If your setup sits in a pending state, there's no published clock to hold it to.

On Magento 2 the mechanism is different, and Google's platform list names WeltPixel among its Magento 2 partners for the feature [2]. Our Magento write-up on Google automated discounts covers that side.

Which purchase action should be primary while automated discounts runs?

Google doesn't say outright, and two of its pages point different ways.

The automated-discounts page: "Automated discounts calculates your gross profit using Primary conversions when they include cart data. Otherwise, automated discounts uses the conversion type measuring Purchase events that has previously included the highest number of carts with the required data." [3] Read alone, that suggests a secondary action with complete carts would do. But Google's cart-data setup guide, for both the Google Ads tag and the Google Analytics methods, says "Ensure that the Purchase conversion's 'Conversion goal and action optimization' is set to Primary" [9], and its cart-data reporting covers conversions that are "biddable purchase conversions" [8]. Neither page says whether a secondary action's carts feed the pricing, and we found no page that does.

On a store with server-side tracking, the usual advice, covered in which Google Ads conversion action should count as primary, is one primary purchase action per account, often the server-side upload because it survives ad blockers and browser limits. That primary action has no carts in it.

Two setups are workable. You can keep the upload primary and the channel's purchase measuring as secondary, so bidding stays on your server-side number. Google says "If there are issues with your conversion setup for automated discounts that result in missing or incorrect purchase conversions, you'll be notified in Merchant Center" [7], and that notification is your signal to revisit. Or you can make the channel's purchase primary and the upload secondary for as long as automated discounts runs, which matches Google's setup steps [9] and means bidding runs on the channel's browser-tag measurement in the meantime.

What breaks either setup is the channel no longer measuring purchases. Two controls do that [13]. The channel's Remove control for conversion tracking deactivates tracking for both ads and free listings while the app stays installed, and the per-event "Don't measure in linked account" option takes the channel's purchase out of the linked Google Ads account, even with the rest of the channel's tracking on. Running a tracking app alongside Shopify's Google & YouTube channel covers both.

If you followed that piece and scoped the channel's purchase out of your account, this is the one case where that choice costs you something. Put purchase back to measuring and keep exactly one purchase action primary, and the double counting that piece warned about stays solved.

What changes in your conversion data once Google starts pricing

The order values get smaller, in steps, and not for everyone.

Google's discount reaches the shopper as a Shopify discount code that is "automatically applied at checkout" [1]. The order Shopify records is the discounted one, and the app sends the order total to every destination it's connected to. An illustrative $80 product with a 10% Google price arrives as $72 of product in the purchase value Meta, Google Ads and GA4 receive (plus the order's tax and shipping, which the app's purchase value includes; our piece on tax and shipping in the purchase value explains why). Revenue per order falls on the Google-priced products. Whether conversion rate rises enough to cover it is the question the feature exists to answer.

The rollout is staged. Optimized prices go to "only 10% of visitors for the first 3 days", then to 90%, and the remaining 10% are held out and "used in tests to estimate your performance" [5]. Google warns its reports may take "a few days or several weeks" [5]. Reading average order value on day 2 tells you almost nothing.

Scale matters too. "Typically, 10-40% of your chosen products are discounted at any time", and the limits you set start at least 5% below the product's current price [4]. Your storefront has obligations while it runs: the Google price has to show on the product page for at least 30 minutes and in cart and checkout for at least 48 hours, only for the product it was issued for [6]. A theme change that drops the Price Block can break the product-page half of that.

One flat detail for reporting. The app passes discount codes to Klaviyo as a property on Placed Order, and its GA4 purchase carries no coupon parameter. To split Google-priced orders from full-price ones, filter by discount code in Shopify's own reports.

How do you confirm Google is receiving the carts?

Look where Google reports cart problems, then check the designations.

1. In Google Ads, open Goals > Diagnostics and find the purchase action that carries cart data [7].
2. Match any warning against Google's listed causes: "The conversion action is not set for purchases", product IDs that don't match Merchant Center, and missing price, currency or quantity [7].
3. For an ID mismatch, compare a product's id in Merchant Center with the item ID the channel reports. Google's rule is that they "must exactly match the id attribute in your Merchant Center feed" [8].
4. After a fix, wait a day or two. Google applies changes "within 24 hours" [7] and says to "allow 24-48 hours for changes to synchronize and the error to resolve" [12].
5. Open Goals > Conversions > Summary and confirm two things: exactly one purchase action is primary, and the channel's purchase has recent conversions in it, whichever designation you chose.

For Black Friday the arithmetic is short. Three days at 10% before the 90% phase [5], up to 48 hours per cart-data fix [7][12], and "within 2-3 business days" when Google reviews a fix to how your store displays its prices [6]. A setup started in the last week before your change freeze has no room for a single failed check.

If you want the server-side purchase as the number you bid on while the Google & YouTube channel keeps measuring the carts Google prices from, WeltPixel Conversion Tracking uploads Shopify orders to Google Ads with the full order total and click IDs, alongside eight other destinations.

FAQ

Do Google's automated discounts work on Shopify?

Yes, through the Google & YouTube app, which Google lists for Shopify [2]. You turn it on under Settings > Automations > Automated Discounts, and Google writes its discounts into Shopify as discount codes applied at checkout [1].

Do I need Shopify Plus for automated discounts?

Google's Shopify setup page doesn't state a plan requirement [1], and we found no Shopify Help Center page on the feature. Treat any claim either way as unconfirmed.

Can a server-side Google Ads upload supply the cart data?

Google's API supports it: "Populating the cart_data field is required to report on basket data" [10]. WeltPixel Conversion Tracking's upload doesn't include items, so on a store using it, the cart data comes from the Google & YouTube channel's measurement.

Does the cart-data action have to be primary?

Google doesn't say. Its automated-discounts page falls back to the Purchase conversion that has carried the most carts when no primary conversion has cart data [3], while its cart-data setup steps say to set the Purchase conversion to Primary [9]. Keeping the channel secondary and watching for Merchant Center's notification [7], or making the channel's purchase primary while the feature runs, are both workable.

Will automated discounts lower the purchase values my ad platforms see?

Yes, on the orders Google prices. The discount is applied at checkout [1], so the order total every destination receives is the discounted one.

Sources

1. Google Merchant Center Help, "Set up automated discounts on the Google & YouTube app on Shopify", support.google.com/merchants/answer/16565024, accessed September 30, 2026
2. Google Merchant Center Help, "Set up automated discounts" (platform list: Google & YouTube app for Shopify; Magento 2 partners), support.google.com/merchants/answer/15152429, accessed September 30, 2026
3. Google Merchant Center Help, "Step 4 of 5: Set up conversions with cart data", support.google.com/merchants/answer/16962427, accessed September 30, 2026
4. Google Merchant Center Help, "About automated discounts", support.google.com/merchants/answer/15010391, accessed September 30, 2026
5. Google Merchant Center Help, "What happens after setting up automated discounts", support.google.com/merchants/answer/16961921, accessed September 30, 2026
6. Google Merchant Center Help, "Fix issues with discounted prices in your online store", support.google.com/merchants/answer/16798068, accessed September 30, 2026
7. Google Merchant Center Help, "Fix issues with purchase conversions and cart data", support.google.com/merchants/answer/16798067, accessed September 30, 2026
8. Google Ads Help, "About conversions with cart data", support.google.com/google-ads/answer/9028254, accessed September 30, 2026
9. Google Ads Help, "Step 1: Choose and deploy an appropriate implementation method", support.google.com/google-ads/answer/14944137, accessed September 30, 2026
10. Google Ads API documentation, "Manage offline conversions", developers.google.com/google-ads/api/docs/conversions/upload-clicks, accessed September 30, 2026
11. Google & YouTube app, Shopify App Store listing (developer Google LLC), apps.shopify.com/google, accessed September 30, 2026
12. Google Ads Help, "About conversions with cart data diagnostics", support.google.com/google-ads/answer/16300258, accessed September 30, 2026
13. Google Ads Help, "Set up conversion tracking with the Google & YouTube app on Shopify" (per-event "Don't measure in linked account"; opting out of conversion tracking), support.google.com/google-ads/answer/13494537, accessed September 30, 2026