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Change prices for Black Friday without Google price mismatches (UK & EU)

Goal

Googlebot compares the price in your feed with the price in your product page's HTML, and a mismatch can get products disapproved. Prices set in Shopify reach Google within about 24 hours, and Google's automatic price updates may not keep up with prices that change more than once a day. For a UK or EU sale to show Google's sale badge, the discount has to be more than 5% and less than 90%, and the normal price must have been charged for 30 days in the past 200. Plan the change, don't flip prices at midnight.

Prompt to copy

Check my planned Black Friday prices before I change anything in Shopify. My store sells to [UK / Ireland / EU countries] and I use the Google & YouTube app.
I'll paste a CSV: Handle | Variant | Current price | Current compare-at price | Planned sale price | Planned compare-at price | Days at the current price in the last 200 days (if known) | Lowest price in the last 30 days (if known) | Market-specific fixed prices? (yes/no).
Use ONLY these rules (from Google Merchant Center Help, Shopify Help and the EU's Your Europe site):
- Google sale badge, UK and EU countries listed by Google: sale price lower than base price, discount more than 5% and less than 90%, base price valid for 30 days within the past 200 days, and both prices shown on the landing page. Even then the badge isn't guaranteed.
- Shopify: compare-at must be higher than price to show a sale. A compare-at of 0.00 is not the same as empty. Fixed market prices override the admin price and compare-at price.
- EU consumers: an announced price reduction must show the lowest price applied in at least the 30 days before the reduction.
For each variant report: Discount % | Sale badge likely? (yes / no, with the rule / unknown, needs price history) | Compare-at problems (not higher, 0.00, inconsistent across variants) | EU prior-price check (OK / compare-at is higher than the 30-day lowest / unknown) | Fixed market price overrides it? | Action.
Then list the variants to fix before the sale starts. Don't decide UK legal questions. Flag them for me to check instead.

Steps

1. Export products (Products › Export) and add your planned sale prices and any price history you have.
2. Run the prompt and fix the flagged rows first.
3. Set the sale with compare-at prices in good time before the sale, not at midnight on the day. Google says prices saved in Shopify reach Google within 24 hours.
4. In Merchant Center, check whether automatic item updates are on. Google says they may not work for prices that change more than once a day, and shouldn't be used for price if your pages show several strikethrough prices.
5. Check that the sale price is in the page HTML, not added later by JavaScript. Use Google's Rich Results Test on two or three sale products.
6. If you use Shopify Catalog, choose in Shopify whether AI agents get the price or the compare-at price as the list price.
7. Watch Merchant Center Diagnostics for 'Mismatched price' during the sale, and reverse the change the same careful way afterwards.

What to check

• No compare-at price was raised just before the sale. In the EU that breaks the 30-day lowest-price rule, and on Google it won't count as the base price.
• Every variant of a product has a consistent compare-at price, so collection pages show the sale.
• Market-specific fixed prices for Ireland or the EU are updated too, because they override admin prices.
• Prices in the HTML, structured data and feed match exactly, in GBP or EUR as the market needs.
• You've checked UK price-reduction rules separately. This workflow doesn't cover UK law.

Sources

Facts on this page were checked against these official pages on 4 November 2026. Rules change, so check the source before you rely on it.

• Google Merchant Center Help: How to fix a mismatched product price
• Google Merchant Center Help: Automatic item updates
• Google Merchant Center Help: About sale prices and promotions (for Shopify users)
• Google Merchant Center Help: How to sync sale prices and promotions from Shopify
• Google Merchant Center Help: Sale price effective date
• Shopify Help: Setting sale prices for products
• Your Europe (European Union): Unfair pricing and price reduction claims

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