Shipping regions specify geographic areas your store will ship to. Grouping shipping destinations into regions makes it easier to create shipping methods. For example, to create a ground shipping method for a U.S.-based store, start by creating a shipping region that includes the 48 contiguous U.S. states.
When a customer enters a shipping address either at checkout or when creating a profile, the logic in the Customer Address widget allows the customer to pick from only countries and regions that are used in enabled shipping methods.
To create a shipping region:
On the Settings tab, click Shipping Methods.
Click New Shipping Region.
Enter a name for the shipping region.
Select one or more countries to ship to and then one or more regions within each selected country.
Tip: When you select a country, all its regions are automatically selected by default. To select only some regions, either deselect the regions you do not want to include or deselect the Select All setting and then individually select regions.
Click Save.