Your 529 Education Savings Plan Credit can only offset tax that you owe.
So, if you're eligible for the maximum $1,500 credit but only owe $1,223 in tax, only $1,223 will be allowed.
See Schedule IN-529, Schedule IN-529: Indiana’s CollegeChoice 529 Education Savings Plan Credit, available at 2023 Individual Income Tax Forms, and Tax Credit FAQ for more information.
