I've had the same issue in regards to the calculation of capital gains from T3 slips, but I believe I have found the following:
On a T3 slip, Capital Gains is reported in Box 21, however, this year the CRA has added boxes 52 (capital gains before June 25) and 53 (capital gains after June 24). It appears (to me) that Turbotax does NOT use Box 21 for the actual tax calculation, but rather will solely rely on information in Box 52 and 53. So if you have a T3 tax slip with only Box 21 completed (and nothing related to Box 52 and 53), you will have to insert the Box 21 amount into Box 52 and/or Box 53 to be captured in the calculation. This seemed to work for me in the calculation of taxes. Does this make sense? Anyone else with the same experience or scenario? Is it "safe" to proceed to file now with NETFILE? Thanks!
