Auto Fill Form fields based on another field's value using a IIF

[JohnW]

Hello once again...I'm back

I am trying to have the value for our Zipcode field to automatically be
added based on what city we select from our combo box for cities.

Zipcode field = Zipcode
City combobox field = lucity

I have tried using the IIF statement IIf([lucity]=Belton,[Zipcode]=29627,0)
placed in the properties of the Zipcode field in the form but it doesn't
work. I have about 12 cities to do this with.

Any suggestions? Thanks