Investors & landlords

You should go back through the investment sale entry to see if you clicked on the "the cost basis is incorrect or missing on my 1099-B " box on the screen where you enter the sale information. If so, uncheck that box.

Otherwise, you should enter as the adjusted cost basis the cost basis reported on the Form 1099-B, assuming it is correct. For some reason, TurboTax thinks that the cost basis needed adjustment and that is why you are seeing that question. If you leave it blank, it may prompt an error message.  @PLV