How to accomplish large data cascading drop-downs?

Suppose your main list has students and location information, so your columns are Last Name, First Name, Email, Region, State, Zip. Since you are also exporting this data to a SharePoint list you need the location information to be exact. This is why I need cascading/dependent drop-downs for location information.

I have tried named ranges which works for the Region(6 items) & State (50 items), so that there are 6 named ranges with the corresponding states in them. However, this method gets a little too much when you get down to Zip in which you need 50 named ranges.

Is there a way, other than named ranges, to get distinct cascading/dependent drop-downs for large lookup datasets?

Thank you.

It sounds like your data is in a tabular format.

With the State dropdown in D2, your zipcodes in column B starting in B2, and your states in A starting in A2, you can use this data validation formula for zips:

=OFFSET(B1,MATCH(D2,A2:A100,0),0,COUNTIF(A2:A100,D2),1)

Adjust accordingly to fit your sheet.