Your Section 1256 Contracts and Straddles are reported on Form 6781. To access Form 6781 in TurboTax (Desktop or Online) type "Form 6781" into Search. Next, click on "Jump to form 6781". This will take you to the screen with "Any Straddles or Section 1256 Contracts?" Answer Yes, and continue to complete Form 6781.
Before reporting you Section 1256 Contracts and Straddles, I recommend (as does the program) you review IRS Form 6781 Instructions. I also recommend you review IRS Publication 550 - Investment Income and Expenses for the special rules and elections that apply to Section 1256 Contracts and Straddles.
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