Unknown cost basis, unknown gain/loss, report on form 8949, where or how do I get this?

[KenH1]

Brokerage statements will not always report the cost basis and/or sales category, even if the information is available right on the 1099-B. The IRS is receiving the 1099-B information from the broker, but is relying on you to report the correct cost basis and category.

To get back to the 1099-B screen:

Federal Taxes > Wages & Income > 

Scroll down to Investment Income, then click Show More

Select Start next to Stocks, Mutual Funds, Bonds, Other 

For unreported cost basis:

Make a reasonable estimate, based on old trade confirmations or historical prices from a source such as www.finance.yahoo.com 

For unreported sales category:

If you held the security less than one year, use code C (short-term, not reported)

If you held the security more than one year, use code F (long-term, not reported)