Since when is the maximum value 5000 for 529 account contributions (for higher education expense purposes)? I contributed $6,000, but TT won't allow more than 5000...?

 There is no federal deduction for making a contribution to a 529 plan. Some states allow a deduction on the state return. If your state is one, it will come up in the state interview; usually in the "Here's how (your state) handles income differently" section.  Turbotax will limit you to your state's deduction limit, For a list, see:

http://www.savingforcollege.com/compare_529_plans/index.php?page=compare_plan_questions&plan_question_ids[]=437&order_by=plan_question_437

Thank you very much.  

Indeed, my State (Indiana) does give a 20% for 529 contributions up to the first $5,000.  It's wonderful.

I was just perplexed as to why TurboTax software would prevent me from typing in a contribution figure greater than $5,000.  I was expecting the software to cap the amount when it is calculating the allowable credit.

Nevertheless, thank you very much for your time.

I contributed to the Indiana 529 plan and had the exact issue as lafiosca . It seems that the field limitations in the TurboTax form need to be adjusted to allow entries greater than $5,000.

@questionperson2021

The way Schedule IN-529: Indiana’s CollegeChoice 529 Education Savings Plan Credit form, found at 2021 Individual Income Tax Forms - DOR, is laid out, even if an amount of over $5,000 is entered, the maximum allowable credit amount would be $1,000, $500 if married filing separately.  

That’s because the allowable credit rate is 20% of the contribution amount, up to a maximum of $1,000 (or $500).