Where do I enter my current year rental losses to carry over

[KenH1]

do you mean, where do you enter your 2015 carryover onto your 2016 return?

[4bccarroll]

No. How/where do I enter my 2016 losses for carry over to 2017?

[KenH1]

If you use TurboTax next year, it will carryover automatically.  You can find the number on line 4 of form 8582 (passive activity loss limitations)