ZipCode Shortcut
The Zipcode is a fastTrack shortcut to form entry
I've seen this technique employed effectively on a few websites - Curious that it is not used more often. I don't know how well this method will work internationally, but assume that some of the same efficiencies apply.
1. Type in a 5-character ZIPCODE:
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2. In the background, a simple lookup engine identifies the appropriate STATE and CITY.
3. If you want to turn the CITY field into a dropdown with multiple choices (as appropriate), you could. But simply pre-populating the CITY field with your "best guess" / biggest town will probably be accurate 95+% of the
You've just filled in 3 postal address fields by entering only 5 characters.