I traded 667 RSUs. 218 were taken for tax, 449 for income. 1099-B only shows 449 shares, not the 218 that were for taxes. TurboTax, is trying to tax my net 449 again.

[TomYoung · Accepted solution]

"TurboTax, is trying to tax my net 449 again. "

That's because you are using the wrong basis when reporting your sale.  Broker's only need to report your "out of pocket" cost for employer stock so the broker is reporting a basis of $0, not the correct basis which is the same as the fair market value of the stock when the RSU vested and the compensation was calculated.  Take the compensation reported on the W-2 created by the vesting and divide that by the GROSS number of shares in the grant.  That's your correct per share basis.

Enter the 1099-B as it reads on the default 1099-B entry form but then click on the "I'll enter additional info on my own" blue button.  On the next page enter the correct basis in the "Corrected cost basis" box.  The correct basis is (number of shares sold) x (correct per share basis, which includes the compensation per share)

TurboTax will report the sale on Form 8949 "as reported by the broker" but will put an adjustment figure into column (g) of the Form, a code "B" into column (f) of the Form, and the correct amount of gain or loss which includes the adjustment.

Tom Young

NOTE: TURBOTAX CHANGES THE SECURITY SALES INTERVIEW JUST ABOUT EVERY SINGLE YEAR.  THE INSTRUCTIONS ON "HOW TO FIX" THE BASIS REFLECT THE STATE OF THE INTERVIEW FOR TAX YEARS 2016 AND 2017.