Why does my tax due not change after I enter my mileage deduction?

[Hal_Al · Accepted solution]

There is no longer (starting in 2018) a mileage deduction for W-2 employees. TurboTax(TT) only lets you enter it, in case your state allows it.

Even when you could deduct it, in the past, it was only a misc. itemized deduction subject to the 2% of AGI threshold.