I have 401k and Roth IRA with my employer. Since its included in my w2 form, should i still list it separately as it asks if i contribute to 401k/Roth IRA while filing?

Do you have a 401k & a ROTH 401K  with the employer ?  

Yes i have both with the employer through vanguard

Ok ... so you do NOT have a ROTH IRA  only the ROTH 401K .... if that is true then you can make a ROTH IRA or Traditional IRA contribution if you qualify to do so ... if you make an IRA contribution in the TT program in the IRA section the program will let you  know if the contribution is too much and the consequences of doing so and the remedy.

No, only enter your W2, it should all be included there in Box 12 of the W2.

Enter amounts shown in box 12 of your W-2 only on TurboTax's W-2 form, nowhere else in TurboTax.

THanks - this is VERY CONFUSING as TurboTax asks me for my W-2 information.  That's good.  BUT THEN in the deductions section - it asks how much my wife and I contributed to a 401k - without stating that if that amount is already entered in the W2 - DO NOT enter it again in deductions.  Your answer clarified this - and TurboTax should fix the deductions section to check if the W2 has a 401k, then warn us not to reenter that amount.

TurboTax has this warning in the On Demand Tax Guidance that you get when you click the Learn More link for a Traditional IRA on the page that asks you to select the kinds of IRAs that you have, telling you that qualified retirement plans like 401(k)s are *not* IRAs.

Dmertz:  THANK YOU VERY MUCH!  really appreciate your additional clarification and confirmation.  Awesome.  I hope someone from Turbotax reads your reply and this thread as i think they can reduce this confusion by not requiring us to click and seek the info as you presented, but to provide a bit of warning/clarification in the entry field screen.  thanks again - your comment is perfect and will let me sleep better.

Nowhere does the program ever ask you to enter the 401K contribution a second time ... read the screen instructions carefully ... the program uses a minimalist  format so as not to overwhelm the user (and is mobile friendly) so if you ever are asked to enter something a second time make sure to read the instructions carefully.

a 401K, solo 401K, IRA, ROTH IRA are all different things.

Many people confuse IRAs with qualified retirement plan, so I agree that it would probably be helpful in the IRA contribution section for TurboTax to say not to enter anything in the IRA contribution section that is reported in box 12 of a W-2.