Open Address Ninja from Apps in your Shopify admin. On the home page, click Block postal codes. In the Postal codes to block card, use the Add a country field to search for a country. A field for that country appears. Enter the codes to block, separated by commas or new lines. Use exact codes like 12345 or SW1A 1AA, or use * to match any characters: 900* blocks every code that starts with 900. Spaces and letter case are ignored. Repeat for each country, up to 20 countries. Click Remove next to a country to delete its list. Click Save and turn on. To change the error message, open the Error message card.
Lists over about 1,200 codes are too large to save. The app shows "The settings for Block postal codes are too large to save. Shorten patterns or remove a group." Use wildcards to shorten the list.
Use cases: Block high-risk fraud zones, restrict delivery to certain areas, manage temporary service disruptions, or meet regional regulations.
Originally from our Help Center