On the T5008, you should make sure that the cost of the stock is shown in Box 20.In case it did not showed in this year in the box 20 ,so you should check your own records for the details of the original purchase of the security and then enter your cost of the securities in Box 20 yourself. Once this information is properly entered, the TurboTax software will automatically calculate the correct capital gain or loss on that security transaction.
You would include the amount in box 20 in your T5008. Usually, your broker will fill this for you, but you still need to verify the amount to reflect your true Adjusted Cost Base (ACB). If your broker leaves this box blank, you must still calculate it and report it. You can ask your broker for information regarding your transactions with them.
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