Box 12 D elected for 401k, do I have to report this if so how

[MargaretL]

All you have to do is enter your W-2 into TurboTax exactly as it appears; no additional entries are required for 401K.  You are receiving a tax break by having your 401K contributions in box 12D - it means you don't pay tax on it, that amount is not included in box 1 of your form w-2.