in Turbotax, a cost must be assigned for every sale. if there is zero cost, for example, an option sold short that expires worthless a zero is required for the cost, not a blank. the only way that may be available to avoid reviewing all these transactions is to enter summary totals on the 8949. then you mail in a download copy of the 1099-B with form 8453. read the instructions. it should be available in Turbotax but if not
https://www.irs.gov/pub/irs-pdf/f8453.pdf
