Changing the masking format for zip or postal codes in Core can be done by entering the appropriate characters in Zip label Format field. This setting is found in the Company Menu>Settings>Global Settings>Custom Labels Screen.
- Go to Company Menu>Settings>Global Settings and click on the Custom Labels option.
- Expand the Address item from the list and select the mask you want for the Zip field from the drop-down list.
- Click Save. Check Customize Labels and Mask for details.