The Google channel supports only carrier-calculated shipping rates for certain shipping carriers and services in Australia, Germany, and the United States. Confirm which shipping carriers and services Google supports on the Google Merchant Help Center. If you use an unsupported shipping carrier or live in another country or region, then you need to need to use custom shipping rates.
If you need to add shipping rates for the Google channel, then you can choose to automatically import shipping settings from your store, or you can set up your shipping rates manually in Google Merchant Center. When you import your shipping settings from your store to use in the Google channel, there are a few considerations to keep in mind:
You can import rates to ship your products to only one country.
You need to have a shipping zone set up for the country where you ship products.
If you don't want to use these shipping rates, then you can set up your shipping rates manually in Google Merchant Center. You can change how shipping rates are set up for the Google channel at any time.
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