Can I claim a long-term capital loss and use the standard deduction?

If you transferred last year's TurboTax return over, you don't have to do a thing—we've already entered it for you.

Otherwise, follow these instructions:

1. Sign in to your TurboTax account and open your return by selecting Continue or Pick up where you left off in the progress tracker.
2. Search for capital loss carryover, and then select the Jump to link in the search results.
3. Select Yes on the screen Did you have investment losses you couldn't claim last year?
4. Enter the info about your capital loss on the following screens.

Or Federal tab > Wages & Income > Capital Loss Carryover, then Edit/Add.

TurboTax FAQ: How do I enter mt capital loss carryover?

Yes the capital loss is separate from the Standard Deduction.  You can get both.  

If you have investment sale losses, after you subtract the losses from your gains you can only deduct up to 3,000 (1,500 MFS) per year. The rest you will have to carryover until it is used up. You can't skip a year.

If it didn’t transfer over from last year then

Enter a Capital Loss Carryover under

Federal Taxes or Personal (Home & Business)

Wages and Income

Then scroll down to Investment Income

Capital Loss Carryovers - Click Start or Revisit

But if you have a negative AGI or negative taxable income it will show up on 1040 BUT it won't reduce the carryover to the next year.

In the Online version you have to save your return with all the worksheet as a pdf file to your computer to see the Capital Loss Carry Over and Carry Forward worksheets.