To enter your corrected cost basis, in the investment section for 1099-B:
- Select to enter your information by transaction.
- On the next screen, you'll enter boxes 1a-1e.
- Directly below these boxes, click the blue button to enter additional Info about this sale, "I'll enter additional info on my own."
- On the next screen, you'll have the option to enter corrected cost basis which is where you can enter your correct amount.
Employee stock options get complicated and often your broker does not have information about your W-2 income when the options vest. I'd recommend being sure you understand how the cost basis is calculated so you know it's correct.
