In the example below the destination address must match 1234 or 4321 in order for this range to be considered a match.
The single rule that you enter must match a valid postcode format for the country that the range applies to. In the example above, the country for this range is Australia. Australia has two valid postcode formats - three digits (e.g. 123) and four digits (1234). Entering a single rule that does not match one of these formats will result in a validation error:
Rules are validated based on their format rather than on whether the postcode itself actually exists. In other words if you enter a made up postcode that is in the correct format, it will pass validation.
Single postcode rules are not case sensitive and you do not need to format single rules with spaces in order for them to be considered valid. For example this rule:
Would be a valid match for the postcode:
While single rules are great for targeting individual postcodes, you should avoid using them in situations where another rule type would be more efficient. For example, this set of single rules:
1000 1001 1002 1003 1004 1005
Would probably be better written using a range rule:
You should use single rules when you have one or more specific postcodes that you want to target that do not really relate to one another in any way (for example they are not part of a sequence). They are also very useful for marking specific postcodes as exclusions.
You should avoid using single rules when the rules you are entering could be expressed more succinctly using another rule type.