Is Illinois teachers TRS tax deductible?

As a deferred compensation plan the TRS contribution amounts are NOT subject to income tax during the year and would not be deductible on your income tax return because the amounts are not reported on your W-2 form in the box 1 gross wages, salaries etc for the year.

The distribution amounts from the TRS plan in future will be reported as taxable income when you start taking the distributions from the TRS plan.