I have modified this module for uk postcodes. It should also still work for zipcodes too.

Basically I have hard coded a '^' in front of each postcode entry and I have also added a zone selector so that you can limit your postcodes to only a UK zone.

What does this mean:

You enter: IV40, IV41, IV42

The system sees:

^IV40, ^IV41, ^IV42

In Regular Expression ^ basically means look at the start of the string i.e. the start of the postcode. It works for me but please test yourself.

Full package - backup first!

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