Capital gains question -- if I sold 100 shares of stock that originally cost me $55 a share, what is the amount I should enter in the Cost column on my return

[Critter1]

You enter the current basis in the stock .... the original cost adjusted by any stock splits or spin offs. If the stock never split or had a spin-off then 100 times $55.

[DJS · Accepted solution]

If you simply sold the original 100 shares then you would report the cost as 100*55 ($5500) plus commissions that you paid on the purchase. However, if for instance there had been a split (say 2:1), and you now held 200 shares and sold 100, the cost of the 100 that you sold would be 1/2 the cost of the original 100 that you purchased (100*27.5 plus 1/2 the original commission). Had there been a spin off and you received other stock or cash as a result then the "cost" calculation can get more complicated and depend on the particular rules of the reorganization.