Hi Justin

I suggest you use something like this:

Create a list of codes and zones like, keeping at least one row free at
the top:

___|__A__|___B____|
_1_|_____|________|
_2_|_001_|_Zone_1_|
_3_|_301_|_Zone_2_|
_4_|_467_|_Zone_1_|
_5_|_568_|_Zone_3_|
_6_|_855_|_Zone_1_|
_7_|_964_|_Zone_2_|


The function for the Zone Column would be:
Assuming the Zip code is in Cell D1
=OFFSET($B$1,MATCH(D1,$A$2:$A$7,1),0)


HTH,

Executor