I do not know my cost basis for 1099b and wont let me go any further

[johnnyontop]

For 1099b the screen for basis not reported to the irs and term is unknown i have entered  all the info from my brokerage box 1b is unknown and i cant go any further

[Vanessa A]

Without the cost basis, you will be taxed on the full amount of the sale including what you paid.  The proper way is that you only pay taxes on the gain of the sale, but in order to do this, you will need to enter what you paid for the stock.

You will need to figure out your cost basis.   If so, use a historical market lookup tool to find the value of the stock on the date you made the purchase.  You can also go back and look at your old investment or bank statements from when you purchased the stock. 

If you absolutely cannot find the cost basis, you can enter $0, but again, you may end up paying more in taxes than you have to.