How do I report in TT, wash sale loss disallowed when Broker does not report cost info to IRS on 1099B

But the Broker does show the wash sale loss disallowed amount  on a statement , Schedule of Realized
Gains and Losses for the same transaction that is on the 1099B
    The statement of Realized Gains and Losses that came with your 1099B  should list the net proceeds, cost/adjusted cost and gain/loss amount.  If you upload (import) your broker's data beware of a Turbo Fatal Error (more later).  If you are manually entering this data on the 8949 Sales and Other Dispositions of Capital Assets then put the net proceeds amount for the wash sale in col. (e), put the cost in col. (f), the difference is the loss (which should also be on the statement they provided) and goes in col. (g) as a positive number (no minus sign).  Be sure to put a "W" in col. (b).

    If you uploaded or imported the brokers' info:    Turbo Tax has a fatal error that could be due to the way information is submitted by the broker during the upload.  Turbo Tax is putting the sales price (net proceeds) on the Imported Broker Transactions Worksheet in both Box 2 and Box 3.  You need to manually remove the net proceeds amount from Box 3 (Cost or other basis) and put in the cost from your broker's Annual Statement Information that came with your broker's 1099.   Box 5 should have the amount of the loss expressed as a positive (no minus sign).  This will carry over correctly to 8959 which is used for Schedule D.  It will also be reported correctly on the Qualified Dividends and Capital Gain Tax Worksheet.  Best of all it will remove the error message.
      Put the amount of the disallowed loss into the wash sale field in TT.  I had to calculate this number since my 1099B did not have a Box 5, but the transanction was flagged as a wash sale. Make sure to enter the disallowed loss as a positive number. On some of the wash sales I had to go to Forms in TT and open the Capital Gain (Loss) Transaction Worksheet. In the Capital Gain (Loss) Transaction Worksheet enter the amount of the disallowed loss in Part 1 Line 1,c,(1) and then again in Part 10 Line 7.  Review Part 11, column h and i for accuracy on the Capital Gain (Loss) Transaction worksheet.   These adjustments will flow to Form 8949 and Schedule D.
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